1378 lines
46 KiB
Java
1378 lines
46 KiB
Java
/*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package org.apache.commons.lang3;
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import java.io.IOException;
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import java.io.Serializable;
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import java.lang.reflect.Array;
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import java.lang.reflect.InvocationTargetException;
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import java.lang.reflect.Method;
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import java.time.Duration;
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import java.util.Collection;
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import java.util.Collections;
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import java.util.Comparator;
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import java.util.Map;
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import java.util.Objects;
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import java.util.TreeSet;
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import java.util.function.Supplier;
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import org.apache.commons.lang3.exception.CloneFailedException;
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import org.apache.commons.lang3.text.StrBuilder;
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import org.apache.commons.lang3.time.DurationUtils;
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/**
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* <p>
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* Operations on {@code Object}.
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* </p>
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*
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* <p>
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* This class tries to handle {@code null} input gracefully. An exception will
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* generally not be thrown for a {@code null} input. Each method documents its
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* behavior in more detail.
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* </p>
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*
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* <p>
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* #ThreadSafe#
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* </p>
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*
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* @since 1.0
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*/
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//@Immutable
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@SuppressWarnings("deprecation") // deprecated class StrBuilder is imported
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// because it is part of the signature of deprecated methods
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public class ObjectUtils {
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// Null
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// -----------------------------------------------------------------------
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/**
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* <p>
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* Class used as a null placeholder where {@code null} has another meaning.
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* </p>
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*
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* <p>
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* For example, in a {@code HashMap} the
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* {@link java.util.HashMap#get(java.lang.Object)} method returns {@code null}
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* if the {@code Map} contains {@code null} or if there is no matching key. The
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* {@code Null} placeholder can be used to distinguish between these two cases.
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* </p>
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*
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* <p>
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* Another example is {@code Hashtable}, where {@code null} cannot be stored.
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* </p>
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*/
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public static class Null implements Serializable {
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/**
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* Required for serialization support. Declare serialization compatibility with
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* Commons Lang 1.0
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*
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* @see java.io.Serializable
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*/
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private static final long serialVersionUID = 7092611880189329093L;
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/**
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* Restricted constructor - singleton.
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*/
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Null() {
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}
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/**
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* <p>
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* Ensure singleton.
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* </p>
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*
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* @return the singleton value
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*/
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private Object readResolve() {
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return NULL;
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}
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}
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private static final char AT_SIGN = '@';
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/**
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* <p>
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* Singleton used as a {@code null} placeholder where {@code null} has another
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* meaning.
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* </p>
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*
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* <p>
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* For example, in a {@code HashMap} the
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* {@link java.util.HashMap#get(java.lang.Object)} method returns {@code null}
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* if the {@code Map} contains {@code null} or if there is no matching key. The
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* {@code Null} placeholder can be used to distinguish between these two cases.
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* </p>
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*
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* <p>
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* Another example is {@code Hashtable}, where {@code null} cannot be stored.
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* </p>
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*
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* <p>
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* This instance is Serializable.
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* </p>
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*/
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public static final Null NULL = new Null();
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/**
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* Checks if all values in the array are not {@code nulls}.
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*
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* <p>
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* If any value is {@code null} or the array is {@code null} then {@code false}
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* is returned. If all elements in array are not {@code null} or the array is
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* empty (contains no elements) {@code true} is returned.
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* </p>
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*
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* <pre>
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* ObjectUtils.allNotNull(*) = true
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* ObjectUtils.allNotNull(*, *) = true
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* ObjectUtils.allNotNull(null) = false
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* ObjectUtils.allNotNull(null, null) = false
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* ObjectUtils.allNotNull(null, *) = false
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* ObjectUtils.allNotNull(*, null) = false
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* ObjectUtils.allNotNull(*, *, null, *) = false
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* </pre>
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*
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* @param values the values to test, may be {@code null} or empty
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* @return {@code false} if there is at least one {@code null} value in the
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* array or the array is {@code null}, {@code true} if all values in the
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* array are not {@code null}s or array contains no elements.
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* @since 3.5
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*/
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public static boolean allNotNull(final Object... values) {
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if (values == null) {
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return false;
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}
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for (final Object val : values) {
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if (val == null) {
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return false;
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}
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}
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return true;
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}
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/**
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* Checks if all values in the given array are {@code null}.
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*
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* <p>
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* If all the values are {@code null} or the array is {@code null} or empty,
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* then {@code true} is returned, otherwise {@code false} is returned.
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* </p>
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*
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* <pre>
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* ObjectUtils.allNull(*) = false
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* ObjectUtils.allNull(*, null) = false
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* ObjectUtils.allNull(null, *) = false
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* ObjectUtils.allNull(null, null, *, *) = false
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* ObjectUtils.allNull(null) = true
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* ObjectUtils.allNull(null, null) = true
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* </pre>
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*
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* @param values the values to test, may be {@code null} or empty
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* @return {@code true} if all values in the array are {@code null}s,
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* {@code false} if there is at least one non-null value in the array.
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* @since 3.11
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*/
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public static boolean allNull(final Object... values) {
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return !anyNotNull(values);
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}
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/**
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* Checks if any value in the given array is not {@code null}.
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*
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* <p>
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* If all the values are {@code null} or the array is {@code null} or empty then
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* {@code false} is returned. Otherwise {@code true} is returned.
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* </p>
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*
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* <pre>
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* ObjectUtils.anyNotNull(*) = true
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* ObjectUtils.anyNotNull(*, null) = true
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* ObjectUtils.anyNotNull(null, *) = true
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* ObjectUtils.anyNotNull(null, null, *, *) = true
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* ObjectUtils.anyNotNull(null) = false
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* ObjectUtils.anyNotNull(null, null) = false
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* </pre>
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*
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* @param values the values to test, may be {@code null} or empty
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* @return {@code true} if there is at least one non-null value in the array,
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* {@code false} if all values in the array are {@code null}s. If the
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* array is {@code null} or empty {@code false} is also returned.
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* @since 3.5
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*/
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public static boolean anyNotNull(final Object... values) {
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return firstNonNull(values) != null;
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}
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/**
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* Checks if any value in the given array is {@code null}.
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*
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* <p>
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* If any of the values are {@code null} or the array is {@code null}, then
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* {@code true} is returned, otherwise {@code false} is returned.
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* </p>
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*
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* <pre>
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* ObjectUtils.anyNull(*) = false
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* ObjectUtils.anyNull(*, *) = false
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* ObjectUtils.anyNull(null) = true
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* ObjectUtils.anyNull(null, null) = true
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* ObjectUtils.anyNull(null, *) = true
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* ObjectUtils.anyNull(*, null) = true
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* ObjectUtils.anyNull(*, *, null, *) = true
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* </pre>
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*
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* @param values the values to test, may be {@code null} or empty
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* @return {@code true} if there is at least one {@code null} value in the
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* array, {@code false} if all the values are non-null. If the array is
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* {@code null} or empty, {@code true} is also returned.
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* @since 3.11
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*/
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public static boolean anyNull(final Object... values) {
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return !allNotNull(values);
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}
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// cloning
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// -----------------------------------------------------------------------
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/**
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* <p>
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* Clone an object.
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* </p>
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*
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* @param <T> the type of the object
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* @param obj the object to clone, null returns null
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* @return the clone if the object implements {@link Cloneable} otherwise
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* {@code null}
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* @throws CloneFailedException if the object is cloneable and the clone
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* operation fails
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* @since 3.0
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*/
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public static <T> T clone(final T obj) {
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if (obj instanceof Cloneable) {
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final Object result;
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if (obj.getClass().isArray()) {
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final Class<?> componentType = obj.getClass().getComponentType();
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if (componentType.isPrimitive()) {
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int length = Array.getLength(obj);
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result = Array.newInstance(componentType, length);
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while (length-- > 0) {
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Array.set(result, length, Array.get(obj, length));
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}
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} else {
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result = ((Object[]) obj).clone();
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}
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} else {
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try {
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final Method clone = obj.getClass().getMethod("clone");
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result = clone.invoke(obj);
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} catch (final NoSuchMethodException e) {
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throw new CloneFailedException(
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"Cloneable type " + obj.getClass().getName() + " has no clone method", e);
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} catch (final IllegalAccessException e) {
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throw new CloneFailedException("Cannot clone Cloneable type " + obj.getClass().getName(), e);
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} catch (final InvocationTargetException e) {
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throw new CloneFailedException("Exception cloning Cloneable type " + obj.getClass().getName(),
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e.getCause());
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}
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}
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@SuppressWarnings("unchecked") // OK because input is of type T
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final T checked = (T) result;
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return checked;
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}
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return null;
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}
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/**
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* <p>
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* Clone an object if possible.
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* </p>
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*
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* <p>
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* This method is similar to {@link #clone(Object)}, but will return the
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* provided instance as the return value instead of {@code null} if the instance
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* is not cloneable. This is more convenient if the caller uses different
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* implementations (e.g. of a service) and some of the implementations do not
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* allow concurrent processing or have state. In such cases the implementation
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* can simply provide a proper clone implementation and the caller's code does
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* not have to change.
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* </p>
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*
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* @param <T> the type of the object
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* @param obj the object to clone, null returns null
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* @return the clone if the object implements {@link Cloneable} otherwise the
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* object itself
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* @throws CloneFailedException if the object is cloneable and the clone
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* operation fails
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* @since 3.0
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*/
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public static <T> T cloneIfPossible(final T obj) {
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final T clone = clone(obj);
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return clone == null ? obj : clone;
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}
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/**
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* <p>
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* Null safe comparison of Comparables. {@code null} is assumed to be less than
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* a non-{@code null} value.
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* </p>
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*
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* @param <T> type of the values processed by this method
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* @param c1 the first comparable, may be null
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* @param c2 the second comparable, may be null
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* @return a negative value if c1 < c2, zero if c1 = c2 and a positive value
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* if c1 > c2
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*/
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public static <T extends Comparable<? super T>> int compare(final T c1, final T c2) {
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return compare(c1, c2, false);
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}
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/**
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* <p>
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* Null safe comparison of Comparables.
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* </p>
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*
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* @param <T> type of the values processed by this method
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* @param c1 the first comparable, may be null
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* @param c2 the second comparable, may be null
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* @param nullGreater if true {@code null} is considered greater than a
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* non-{@code null} value or if false {@code null} is
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* considered less than a Non-{@code null} value
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* @return a negative value if c1 < c2, zero if c1 = c2 and a positive value
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* if c1 > c2
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* @see java.util.Comparator#compare(Object, Object)
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*/
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public static <T extends Comparable<? super T>> int compare(final T c1, final T c2, final boolean nullGreater) {
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if (c1 == c2) {
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return 0;
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} else if (c1 == null) {
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return nullGreater ? 1 : -1;
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} else if (c2 == null) {
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return nullGreater ? -1 : 1;
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}
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return c1.compareTo(c2);
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}
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/**
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* This method returns the provided value unchanged. This can prevent javac from
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* inlining a constant field, e.g.,
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*
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* <pre>
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* public final static boolean MAGIC_FLAG = ObjectUtils.CONST(true);
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* </pre>
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*
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* This way any jars that refer to this field do not have to recompile
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* themselves if the field's value changes at some future date.
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*
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* @param v the boolean value to return
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* @return the boolean v, unchanged
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* @since 3.2
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*/
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public static boolean CONST(final boolean v) {
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return v;
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}
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/**
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* This method returns the provided value unchanged. This can prevent javac from
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* inlining a constant field, e.g.,
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*
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* <pre>
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* public final static byte MAGIC_BYTE = ObjectUtils.CONST((byte) 127);
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* </pre>
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*
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* This way any jars that refer to this field do not have to recompile
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* themselves if the field's value changes at some future date.
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*
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* @param v the byte value to return
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* @return the byte v, unchanged
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* @since 3.2
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*/
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public static byte CONST(final byte v) {
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return v;
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}
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/**
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* This method returns the provided value unchanged. This can prevent javac from
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* inlining a constant field, e.g.,
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*
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* <pre>
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* public final static char MAGIC_CHAR = ObjectUtils.CONST('a');
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* </pre>
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*
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* This way any jars that refer to this field do not have to recompile
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* themselves if the field's value changes at some future date.
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*
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* @param v the char value to return
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* @return the char v, unchanged
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* @since 3.2
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*/
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public static char CONST(final char v) {
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return v;
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}
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|
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/**
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* This method returns the provided value unchanged. This can prevent javac from
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* inlining a constant field, e.g.,
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*
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* <pre>
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* public final static double MAGIC_DOUBLE = ObjectUtils.CONST(1.0);
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* </pre>
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*
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* This way any jars that refer to this field do not have to recompile
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* themselves if the field's value changes at some future date.
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*
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* @param v the double value to return
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* @return the double v, unchanged
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* @since 3.2
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*/
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public static double CONST(final double v) {
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return v;
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}
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|
|
|
/**
|
|
* This method returns the provided value unchanged. This can prevent javac from
|
|
* inlining a constant field, e.g.,
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*
|
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* <pre>
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* public final static float MAGIC_FLOAT = ObjectUtils.CONST(1.0f);
|
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* </pre>
|
|
*
|
|
* This way any jars that refer to this field do not have to recompile
|
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* themselves if the field's value changes at some future date.
|
|
*
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* @param v the float value to return
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* @return the float v, unchanged
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* @since 3.2
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*/
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public static float CONST(final float v) {
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return v;
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}
|
|
|
|
/**
|
|
* This method returns the provided value unchanged. This can prevent javac from
|
|
* inlining a constant field, e.g.,
|
|
*
|
|
* <pre>
|
|
* public final static int MAGIC_INT = ObjectUtils.CONST(123);
|
|
* </pre>
|
|
*
|
|
* This way any jars that refer to this field do not have to recompile
|
|
* themselves if the field's value changes at some future date.
|
|
*
|
|
* @param v the int value to return
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|
* @return the int v, unchanged
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|
* @since 3.2
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|
*/
|
|
public static int CONST(final int v) {
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return v;
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|
}
|
|
|
|
/**
|
|
* This method returns the provided value unchanged. This can prevent javac from
|
|
* inlining a constant field, e.g.,
|
|
*
|
|
* <pre>
|
|
* public final static long MAGIC_LONG = ObjectUtils.CONST(123L);
|
|
* </pre>
|
|
*
|
|
* This way any jars that refer to this field do not have to recompile
|
|
* themselves if the field's value changes at some future date.
|
|
*
|
|
* @param v the long value to return
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* @return the long v, unchanged
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* @since 3.2
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|
*/
|
|
public static long CONST(final long v) {
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return v;
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|
}
|
|
|
|
/**
|
|
* This method returns the provided value unchanged. This can prevent javac from
|
|
* inlining a constant field, e.g.,
|
|
*
|
|
* <pre>
|
|
* public final static short MAGIC_SHORT = ObjectUtils.CONST((short) 123);
|
|
* </pre>
|
|
*
|
|
* This way any jars that refer to this field do not have to recompile
|
|
* themselves if the field's value changes at some future date.
|
|
*
|
|
* @param v the short value to return
|
|
* @return the short v, unchanged
|
|
* @since 3.2
|
|
*/
|
|
public static short CONST(final short v) {
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|
return v;
|
|
}
|
|
|
|
/**
|
|
* This method returns the provided value unchanged. This can prevent javac from
|
|
* inlining a constant field, e.g.,
|
|
*
|
|
* <pre>
|
|
* public final static String MAGIC_STRING = ObjectUtils.CONST("abc");
|
|
* </pre>
|
|
*
|
|
* This way any jars that refer to this field do not have to recompile
|
|
* themselves if the field's value changes at some future date.
|
|
*
|
|
* @param <T> the Object type
|
|
* @param v the genericized Object value to return (typically a String).
|
|
* @return the genericized Object v, unchanged (typically a String).
|
|
* @since 3.2
|
|
*/
|
|
public static <T> T CONST(final T v) {
|
|
return v;
|
|
}
|
|
|
|
/**
|
|
* This method returns the provided value unchanged. This can prevent javac from
|
|
* inlining a constant field, e.g.,
|
|
*
|
|
* <pre>
|
|
* public final static byte MAGIC_BYTE = ObjectUtils.CONST_BYTE(127);
|
|
* </pre>
|
|
*
|
|
* This way any jars that refer to this field do not have to recompile
|
|
* themselves if the field's value changes at some future date.
|
|
*
|
|
* @param v the byte literal (as an int) value to return
|
|
* @throws IllegalArgumentException if the value passed to v is larger than a
|
|
* byte, that is, smaller than -128 or larger
|
|
* than 127.
|
|
* @return the byte v, unchanged
|
|
* @since 3.2
|
|
*/
|
|
public static byte CONST_BYTE(final int v) {
|
|
if (v < Byte.MIN_VALUE || v > Byte.MAX_VALUE) {
|
|
throw new IllegalArgumentException(
|
|
"Supplied value must be a valid byte literal between -128 and 127: [" + v + "]");
|
|
}
|
|
return (byte) v;
|
|
}
|
|
|
|
/**
|
|
* This method returns the provided value unchanged. This can prevent javac from
|
|
* inlining a constant field, e.g.,
|
|
*
|
|
* <pre>
|
|
* public final static short MAGIC_SHORT = ObjectUtils.CONST_SHORT(127);
|
|
* </pre>
|
|
*
|
|
* This way any jars that refer to this field do not have to recompile
|
|
* themselves if the field's value changes at some future date.
|
|
*
|
|
* @param v the short literal (as an int) value to return
|
|
* @throws IllegalArgumentException if the value passed to v is larger than a
|
|
* short, that is, smaller than -32768 or
|
|
* larger than 32767.
|
|
* @return the byte v, unchanged
|
|
* @since 3.2
|
|
*/
|
|
public static short CONST_SHORT(final int v) {
|
|
if (v < Short.MIN_VALUE || v > Short.MAX_VALUE) {
|
|
throw new IllegalArgumentException(
|
|
"Supplied value must be a valid byte literal between -32768 and 32767: [" + v + "]");
|
|
}
|
|
return (short) v;
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Returns a default value if the object passed is {@code null}.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.defaultIfNull(null, null) = null
|
|
* ObjectUtils.defaultIfNull(null, "") = ""
|
|
* ObjectUtils.defaultIfNull(null, "zz") = "zz"
|
|
* ObjectUtils.defaultIfNull("abc", *) = "abc"
|
|
* ObjectUtils.defaultIfNull(Boolean.TRUE, *) = Boolean.TRUE
|
|
* </pre>
|
|
*
|
|
* @param <T> the type of the object
|
|
* @param object the {@code Object} to test, may be {@code null}
|
|
* @param defaultValue the default value to return, may be {@code null}
|
|
* @return {@code object} if it is not {@code null}, defaultValue otherwise TODO
|
|
* Rename to getIfNull in 4.0
|
|
*/
|
|
public static <T> T defaultIfNull(final T object, final T defaultValue) {
|
|
return object != null ? object : defaultValue;
|
|
}
|
|
|
|
// Null-safe equals/hashCode
|
|
// -----------------------------------------------------------------------
|
|
/**
|
|
* <p>
|
|
* Compares two objects for equality, where either one or both objects may be
|
|
* {@code null}.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.equals(null, null) = true
|
|
* ObjectUtils.equals(null, "") = false
|
|
* ObjectUtils.equals("", null) = false
|
|
* ObjectUtils.equals("", "") = true
|
|
* ObjectUtils.equals(Boolean.TRUE, null) = false
|
|
* ObjectUtils.equals(Boolean.TRUE, "true") = false
|
|
* ObjectUtils.equals(Boolean.TRUE, Boolean.TRUE) = true
|
|
* ObjectUtils.equals(Boolean.TRUE, Boolean.FALSE) = false
|
|
* </pre>
|
|
*
|
|
* @param object1 the first object, may be {@code null}
|
|
* @param object2 the second object, may be {@code null}
|
|
* @return {@code true} if the values of both objects are the same
|
|
* @deprecated this method has been replaced by
|
|
* {@code java.util.Objects.equals(Object, Object)} in Java 7 and
|
|
* will be removed from future releases.
|
|
*/
|
|
@Deprecated
|
|
public static boolean equals(final Object object1, final Object object2) {
|
|
if (object1 == object2) {
|
|
return true;
|
|
}
|
|
if (object1 == null || object2 == null) {
|
|
return false;
|
|
}
|
|
return object1.equals(object2);
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Returns the first value in the array which is not {@code null}. If all the
|
|
* values are {@code null} or the array is {@code null} or empty then
|
|
* {@code null} is returned.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.firstNonNull(null, null) = null
|
|
* ObjectUtils.firstNonNull(null, "") = ""
|
|
* ObjectUtils.firstNonNull(null, null, "") = ""
|
|
* ObjectUtils.firstNonNull(null, "zz") = "zz"
|
|
* ObjectUtils.firstNonNull("abc", *) = "abc"
|
|
* ObjectUtils.firstNonNull(null, "xyz", *) = "xyz"
|
|
* ObjectUtils.firstNonNull(Boolean.TRUE, *) = Boolean.TRUE
|
|
* ObjectUtils.firstNonNull() = null
|
|
* </pre>
|
|
*
|
|
* @param <T> the component type of the array
|
|
* @param values the values to test, may be {@code null} or empty
|
|
* @return the first value from {@code values} which is not {@code null}, or
|
|
* {@code null} if there are no non-null values
|
|
* @since 3.0
|
|
*/
|
|
@SafeVarargs
|
|
public static <T> T firstNonNull(final T... values) {
|
|
if (values != null) {
|
|
for (final T val : values) {
|
|
if (val != null) {
|
|
return val;
|
|
}
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Executes the given suppliers in order and returns the first return value
|
|
* where a value other than {@code null} is returned. Once a non-{@code null}
|
|
* value is obtained, all following suppliers are not executed anymore. If all
|
|
* the return values are {@code null} or no suppliers are provided then
|
|
* {@code null} is returned.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.firstNonNullLazy(null, () -> null) = null
|
|
* ObjectUtils.firstNonNullLazy(() -> null, () -> "") = ""
|
|
* ObjectUtils.firstNonNullLazy(() -> "", () -> throw new IllegalStateException()) = ""
|
|
* ObjectUtils.firstNonNullLazy(() -> null, () -> "zz) = "zz"
|
|
* ObjectUtils.firstNonNullLazy() = null
|
|
* </pre>
|
|
*
|
|
* @param <T> the type of the return values
|
|
* @param suppliers the suppliers returning the values to test. {@code null}
|
|
* values are ignored. Suppliers may return {@code null} or a
|
|
* value of type @{code T}
|
|
* @return the first return value from {@code suppliers} which is not
|
|
* {@code null}, or {@code null} if there are no non-null values
|
|
* @since 3.10
|
|
*/
|
|
@SafeVarargs
|
|
public static <T> T getFirstNonNull(final Supplier<T>... suppliers) {
|
|
if (suppliers != null) {
|
|
for (final Supplier<T> supplier : suppliers) {
|
|
if (supplier != null) {
|
|
final T value = supplier.get();
|
|
if (value != null) {
|
|
return value;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Returns the given {@code object} is it is non-null, otherwise returns the
|
|
* Supplier's {@link Supplier#get()} value.
|
|
* </p>
|
|
*
|
|
* <p>
|
|
* The caller responsible for thread-safety and exception handling of default
|
|
* value supplier.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.getIfNull(null, () -> null) = null
|
|
* ObjectUtils.getIfNull(null, null) = null
|
|
* ObjectUtils.getIfNull(null, () -> "") = ""
|
|
* ObjectUtils.getIfNull(null, () -> "zz") = "zz"
|
|
* ObjectUtils.getIfNull("abc", *) = "abc"
|
|
* ObjectUtils.getIfNull(Boolean.TRUE, *) = Boolean.TRUE
|
|
* </pre>
|
|
*
|
|
* @param <T> the type of the object
|
|
* @param object the {@code Object} to test, may be {@code null}
|
|
* @param defaultSupplier the default value to return, may be {@code null}
|
|
* @return {@code object} if it is not {@code null},
|
|
* {@code defaultValueSupplier.get()} otherwise
|
|
* @since 3.10
|
|
*/
|
|
public static <T> T getIfNull(final T object, final Supplier<T> defaultSupplier) {
|
|
return object != null ? object : defaultSupplier == null ? null : defaultSupplier.get();
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Gets the hash code of an object returning zero when the object is
|
|
* {@code null}.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.hashCode(null) = 0
|
|
* ObjectUtils.hashCode(obj) = obj.hashCode()
|
|
* </pre>
|
|
*
|
|
* @param obj the object to obtain the hash code of, may be {@code null}
|
|
* @return the hash code of the object, or zero if null
|
|
* @since 2.1
|
|
* @deprecated this method has been replaced by
|
|
* {@code java.util.Objects.hashCode(Object)} in Java 7 and will be
|
|
* removed in future releases
|
|
*/
|
|
@Deprecated
|
|
public static int hashCode(final Object obj) {
|
|
// hashCode(Object) retained for performance, as hash code is often critical
|
|
return obj == null ? 0 : obj.hashCode();
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Gets the hash code for multiple objects.
|
|
* </p>
|
|
*
|
|
* <p>
|
|
* This allows a hash code to be rapidly calculated for a number of objects. The
|
|
* hash code for a single object is the <em>not</em> same as
|
|
* {@link #hashCode(Object)}. The hash code for multiple objects is the same as
|
|
* that calculated by an {@code ArrayList} containing the specified objects.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.hashCodeMulti() = 1
|
|
* ObjectUtils.hashCodeMulti((Object[]) null) = 1
|
|
* ObjectUtils.hashCodeMulti(a) = 31 + a.hashCode()
|
|
* ObjectUtils.hashCodeMulti(a,b) = (31 + a.hashCode()) * 31 + b.hashCode()
|
|
* ObjectUtils.hashCodeMulti(a,b,c) = ((31 + a.hashCode()) * 31 + b.hashCode()) * 31 + c.hashCode()
|
|
* </pre>
|
|
*
|
|
* @param objects the objects to obtain the hash code of, may be {@code null}
|
|
* @return the hash code of the objects, or zero if null
|
|
* @since 3.0
|
|
* @deprecated this method has been replaced by
|
|
* {@code java.util.Objects.hash(Object...)} in Java 7 and will be
|
|
* removed in future releases.
|
|
*/
|
|
@Deprecated
|
|
public static int hashCodeMulti(final Object... objects) {
|
|
int hash = 1;
|
|
if (objects != null) {
|
|
for (final Object object : objects) {
|
|
final int tmpHash = hashCode(object);
|
|
hash = hash * 31 + tmpHash;
|
|
}
|
|
}
|
|
return hash;
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Appends the toString that would be produced by {@code Object} if a class did
|
|
* not override toString itself. {@code null} will throw a NullPointerException
|
|
* for either of the two parameters.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.identityToString(appendable, "") = appendable.append("java.lang.String@1e23"
|
|
* ObjectUtils.identityToString(appendable, Boolean.TRUE) = appendable.append("java.lang.Boolean@7fa"
|
|
* ObjectUtils.identityToString(appendable, Boolean.TRUE) = appendable.append("java.lang.Boolean@7fa")
|
|
* </pre>
|
|
*
|
|
* @param appendable the appendable to append to
|
|
* @param object the object to create a toString for
|
|
* @throws IOException if an I/O error occurs.
|
|
* @since 3.2
|
|
*/
|
|
public static void identityToString(final Appendable appendable, final Object object) throws IOException {
|
|
Validate.notNull(object, "object");
|
|
appendable.append(object.getClass().getName()).append(AT_SIGN)
|
|
.append(Integer.toHexString(System.identityHashCode(object)));
|
|
}
|
|
|
|
// Identity ToString
|
|
// -----------------------------------------------------------------------
|
|
/**
|
|
* <p>
|
|
* Gets the toString that would be produced by {@code Object} if a class did not
|
|
* override toString itself. {@code null} will return {@code null}.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.identityToString(null) = null
|
|
* ObjectUtils.identityToString("") = "java.lang.String@1e23"
|
|
* ObjectUtils.identityToString(Boolean.TRUE) = "java.lang.Boolean@7fa"
|
|
* </pre>
|
|
*
|
|
* @param object the object to create a toString for, may be {@code null}
|
|
* @return the default toString text, or {@code null} if {@code null} passed in
|
|
*/
|
|
public static String identityToString(final Object object) {
|
|
if (object == null) {
|
|
return null;
|
|
}
|
|
final String name = object.getClass().getName();
|
|
final String hexString = Integer.toHexString(System.identityHashCode(object));
|
|
final StringBuilder builder = new StringBuilder(name.length() + 1 + hexString.length());
|
|
// @formatter:off
|
|
builder.append(name)
|
|
.append(AT_SIGN)
|
|
.append(hexString);
|
|
// @formatter:on
|
|
return builder.toString();
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Appends the toString that would be produced by {@code Object} if a class did
|
|
* not override toString itself. {@code null} will throw a NullPointerException
|
|
* for either of the two parameters.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.identityToString(builder, "") = builder.append("java.lang.String@1e23"
|
|
* ObjectUtils.identityToString(builder, Boolean.TRUE) = builder.append("java.lang.Boolean@7fa"
|
|
* ObjectUtils.identityToString(builder, Boolean.TRUE) = builder.append("java.lang.Boolean@7fa")
|
|
* </pre>
|
|
*
|
|
* @param builder the builder to append to
|
|
* @param object the object to create a toString for
|
|
* @since 3.2
|
|
* @deprecated as of 3.6, because StrBuilder was moved to commons-text, use one
|
|
* of the other {@code identityToString} methods instead
|
|
*/
|
|
@Deprecated
|
|
public static void identityToString(final StrBuilder builder, final Object object) {
|
|
Validate.notNull(object, "object");
|
|
final String name = object.getClass().getName();
|
|
final String hexString = Integer.toHexString(System.identityHashCode(object));
|
|
builder.ensureCapacity(builder.length() + name.length() + 1 + hexString.length());
|
|
builder.append(name).append(AT_SIGN).append(hexString);
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Appends the toString that would be produced by {@code Object} if a class did
|
|
* not override toString itself. {@code null} will throw a NullPointerException
|
|
* for either of the two parameters.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.identityToString(buf, "") = buf.append("java.lang.String@1e23"
|
|
* ObjectUtils.identityToString(buf, Boolean.TRUE) = buf.append("java.lang.Boolean@7fa"
|
|
* ObjectUtils.identityToString(buf, Boolean.TRUE) = buf.append("java.lang.Boolean@7fa")
|
|
* </pre>
|
|
*
|
|
* @param buffer the buffer to append to
|
|
* @param object the object to create a toString for
|
|
* @since 2.4
|
|
*/
|
|
public static void identityToString(final StringBuffer buffer, final Object object) {
|
|
Validate.notNull(object, "object");
|
|
final String name = object.getClass().getName();
|
|
final String hexString = Integer.toHexString(System.identityHashCode(object));
|
|
buffer.ensureCapacity(buffer.length() + name.length() + 1 + hexString.length());
|
|
buffer.append(name).append(AT_SIGN).append(hexString);
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Appends the toString that would be produced by {@code Object} if a class did
|
|
* not override toString itself. {@code null} will throw a NullPointerException
|
|
* for either of the two parameters.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.identityToString(builder, "") = builder.append("java.lang.String@1e23"
|
|
* ObjectUtils.identityToString(builder, Boolean.TRUE) = builder.append("java.lang.Boolean@7fa"
|
|
* ObjectUtils.identityToString(builder, Boolean.TRUE) = builder.append("java.lang.Boolean@7fa")
|
|
* </pre>
|
|
*
|
|
* @param builder the builder to append to
|
|
* @param object the object to create a toString for
|
|
* @since 3.2
|
|
*/
|
|
public static void identityToString(final StringBuilder builder, final Object object) {
|
|
Validate.notNull(object, "object");
|
|
final String name = object.getClass().getName();
|
|
final String hexString = Integer.toHexString(System.identityHashCode(object));
|
|
builder.ensureCapacity(builder.length() + name.length() + 1 + hexString.length());
|
|
builder.append(name).append(AT_SIGN).append(hexString);
|
|
}
|
|
|
|
// Constants (LANG-816):
|
|
/*
|
|
* These methods ensure constants are not inlined by javac. For example,
|
|
* typically a developer might declare a constant like so:
|
|
*
|
|
* public final static int MAGIC_NUMBER = 5;
|
|
*
|
|
* Should a different jar file refer to this, and the MAGIC_NUMBER is changed a
|
|
* later date (e.g., MAGIC_NUMBER = 6), the different jar file will need to
|
|
* recompile itself. This is because javac typically inlines the primitive or
|
|
* String constant directly into the bytecode, and removes the reference to the
|
|
* MAGIC_NUMBER field.
|
|
*
|
|
* To help the other jar (so that it does not need to recompile when constants
|
|
* are changed) the original developer can declare their constant using one of
|
|
* the CONST() utility methods, instead:
|
|
*
|
|
* public final static int MAGIC_NUMBER = CONST(5);
|
|
*/
|
|
|
|
// Empty checks
|
|
// -----------------------------------------------------------------------
|
|
/**
|
|
* <p>
|
|
* Checks if an Object is empty or null.
|
|
* </p>
|
|
*
|
|
* The following types are supported:
|
|
* <ul>
|
|
* <li>{@link CharSequence}: Considered empty if its length is zero.</li>
|
|
* <li>{@code Array}: Considered empty if its length is zero.</li>
|
|
* <li>{@link Collection}: Considered empty if it has zero elements.</li>
|
|
* <li>{@link Map}: Considered empty if it has zero key-value mappings.</li>
|
|
* </ul>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.isEmpty(null) = true
|
|
* ObjectUtils.isEmpty("") = true
|
|
* ObjectUtils.isEmpty("ab") = false
|
|
* ObjectUtils.isEmpty(new int[]{}) = true
|
|
* ObjectUtils.isEmpty(new int[]{1,2,3}) = false
|
|
* ObjectUtils.isEmpty(1234) = false
|
|
* </pre>
|
|
*
|
|
* @param object the {@code Object} to test, may be {@code null}
|
|
* @return {@code true} if the object has a supported type and is empty or null,
|
|
* {@code false} otherwise
|
|
* @since 3.9
|
|
*/
|
|
public static boolean isEmpty(final Object object) {
|
|
if (object == null) {
|
|
return true;
|
|
}
|
|
if (object instanceof CharSequence) {
|
|
return ((CharSequence) object).length() == 0;
|
|
}
|
|
if (object.getClass().isArray()) {
|
|
return Array.getLength(object) == 0;
|
|
}
|
|
if (object instanceof Collection<?>) {
|
|
return ((Collection<?>) object).isEmpty();
|
|
}
|
|
if (object instanceof Map<?, ?>) {
|
|
return ((Map<?, ?>) object).isEmpty();
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Checks if an Object is not empty and not null.
|
|
* </p>
|
|
*
|
|
* The following types are supported:
|
|
* <ul>
|
|
* <li>{@link CharSequence}: Considered empty if its length is zero.</li>
|
|
* <li>{@code Array}: Considered empty if its length is zero.</li>
|
|
* <li>{@link Collection}: Considered empty if it has zero elements.</li>
|
|
* <li>{@link Map}: Considered empty if it has zero key-value mappings.</li>
|
|
* </ul>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.isNotEmpty(null) = false
|
|
* ObjectUtils.isNotEmpty("") = false
|
|
* ObjectUtils.isNotEmpty("ab") = true
|
|
* ObjectUtils.isNotEmpty(new int[]{}) = false
|
|
* ObjectUtils.isNotEmpty(new int[]{1,2,3}) = true
|
|
* ObjectUtils.isNotEmpty(1234) = true
|
|
* </pre>
|
|
*
|
|
* @param object the {@code Object} to test, may be {@code null}
|
|
* @return {@code true} if the object has an unsupported type or is not empty
|
|
* and not null, {@code false} otherwise
|
|
* @since 3.9
|
|
*/
|
|
public static boolean isNotEmpty(final Object object) {
|
|
return !isEmpty(object);
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Null safe comparison of Comparables.
|
|
* </p>
|
|
*
|
|
* @param <T> type of the values processed by this method
|
|
* @param values the set of comparable values, may be null
|
|
* @return
|
|
* <ul>
|
|
* <li>If any objects are non-null and unequal, the greater object.
|
|
* <li>If all objects are non-null and equal, the first.
|
|
* <li>If any of the comparables are null, the greater of the non-null
|
|
* objects.
|
|
* <li>If all the comparables are null, null is returned.
|
|
* </ul>
|
|
*/
|
|
@SafeVarargs
|
|
public static <T extends Comparable<? super T>> T max(final T... values) {
|
|
T result = null;
|
|
if (values != null) {
|
|
for (final T value : values) {
|
|
if (compare(value, result, false) > 0) {
|
|
result = value;
|
|
}
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* Find the "best guess" middle value among comparables. If there is an even
|
|
* number of total values, the lower of the two middle values will be returned.
|
|
*
|
|
* @param <T> type of values processed by this method
|
|
* @param comparator to use for comparisons
|
|
* @param items to compare
|
|
* @return T at middle position
|
|
* @throws NullPointerException if items or comparator is {@code null}
|
|
* @throws IllegalArgumentException if items is empty or contains {@code null}
|
|
* values
|
|
* @since 3.0.1
|
|
*/
|
|
@SafeVarargs
|
|
public static <T> T median(final Comparator<T> comparator, final T... items) {
|
|
Validate.notEmpty(items, "null/empty items");
|
|
Validate.noNullElements(items);
|
|
Validate.notNull(comparator, "comparator");
|
|
final TreeSet<T> sort = new TreeSet<>(comparator);
|
|
Collections.addAll(sort, items);
|
|
@SuppressWarnings("unchecked") // we know all items added were T instances
|
|
final T result = (T) sort.toArray()[(sort.size() - 1) / 2];
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* Find the "best guess" middle value among comparables. If there is an even
|
|
* number of total values, the lower of the two middle values will be returned.
|
|
*
|
|
* @param <T> type of values processed by this method
|
|
* @param items to compare
|
|
* @return T at middle position
|
|
* @throws NullPointerException if items is {@code null}
|
|
* @throws IllegalArgumentException if items is empty or contains {@code null}
|
|
* values
|
|
* @since 3.0.1
|
|
*/
|
|
@SafeVarargs
|
|
public static <T extends Comparable<? super T>> T median(final T... items) {
|
|
Validate.notEmpty(items);
|
|
Validate.noNullElements(items);
|
|
final TreeSet<T> sort = new TreeSet<>();
|
|
Collections.addAll(sort, items);
|
|
@SuppressWarnings("unchecked") // we know all items added were T instances
|
|
final T result = (T) sort.toArray()[(sort.size() - 1) / 2];
|
|
return result;
|
|
}
|
|
|
|
// Comparable
|
|
// -----------------------------------------------------------------------
|
|
/**
|
|
* <p>
|
|
* Null safe comparison of Comparables.
|
|
* </p>
|
|
*
|
|
* @param <T> type of the values processed by this method
|
|
* @param values the set of comparable values, may be null
|
|
* @return
|
|
* <ul>
|
|
* <li>If any objects are non-null and unequal, the lesser object.
|
|
* <li>If all objects are non-null and equal, the first.
|
|
* <li>If any of the comparables are null, the lesser of the non-null
|
|
* objects.
|
|
* <li>If all the comparables are null, null is returned.
|
|
* </ul>
|
|
*/
|
|
@SafeVarargs
|
|
public static <T extends Comparable<? super T>> T min(final T... values) {
|
|
T result = null;
|
|
if (values != null) {
|
|
for (final T value : values) {
|
|
if (compare(value, result, true) < 0) {
|
|
result = value;
|
|
}
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Compares two objects for inequality, where either one or both objects may be
|
|
* {@code null}.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.notEqual(null, null) = false
|
|
* ObjectUtils.notEqual(null, "") = true
|
|
* ObjectUtils.notEqual("", null) = true
|
|
* ObjectUtils.notEqual("", "") = false
|
|
* ObjectUtils.notEqual(Boolean.TRUE, null) = true
|
|
* ObjectUtils.notEqual(Boolean.TRUE, "true") = true
|
|
* ObjectUtils.notEqual(Boolean.TRUE, Boolean.TRUE) = false
|
|
* ObjectUtils.notEqual(Boolean.TRUE, Boolean.FALSE) = true
|
|
* </pre>
|
|
*
|
|
* @param object1 the first object, may be {@code null}
|
|
* @param object2 the second object, may be {@code null}
|
|
* @return {@code false} if the values of both objects are the same
|
|
*/
|
|
public static boolean notEqual(final Object object1, final Object object2) {
|
|
return !equals(object1, object2);
|
|
}
|
|
|
|
/**
|
|
* Checks that the specified object reference is not {@code null} or empty per
|
|
* {@link #isEmpty(Object)}. Use this method for validation, for example:
|
|
*
|
|
* <blockquote>
|
|
*
|
|
* <pre>
|
|
* public Foo(Bar bar) {
|
|
* this.bar = Objects.requireNonEmpty(bar);
|
|
* }
|
|
* </pre>
|
|
*
|
|
* </blockquote>
|
|
*
|
|
* @param <T> the type of the reference.
|
|
* @param obj the object reference to check for nullity.
|
|
* @return {@code obj} if not {@code null}.
|
|
* @throws NullPointerException if {@code obj} is {@code null}.
|
|
* @throws IllegalArgumentException if {@code obj} is empty per
|
|
* {@link #isEmpty(Object)}.
|
|
* @see #isEmpty(Object)
|
|
* @since 3.12.0
|
|
*/
|
|
public static <T> T requireNonEmpty(final T obj) {
|
|
return requireNonEmpty(obj, "object");
|
|
}
|
|
|
|
/**
|
|
* Checks that the specified object reference is not {@code null} or empty per
|
|
* {@link #isEmpty(Object)}. Use this method for validation, for example:
|
|
*
|
|
* <blockquote>
|
|
*
|
|
* <pre>
|
|
* public Foo(Bar bar) {
|
|
* this.bar = Objects.requireNonEmpty(bar, "bar");
|
|
* }
|
|
* </pre>
|
|
*
|
|
* </blockquote>
|
|
*
|
|
* @param <T> the type of the reference.
|
|
* @param obj the object reference to check for nullity.
|
|
* @param message the exception message.
|
|
* @return {@code obj} if not {@code null}.
|
|
* @throws NullPointerException if {@code obj} is {@code null}.
|
|
* @throws IllegalArgumentException if {@code obj} is empty per
|
|
* {@link #isEmpty(Object)}.
|
|
* @see #isEmpty(Object)
|
|
* @since 3.12.0
|
|
*/
|
|
public static <T> T requireNonEmpty(final T obj, final String message) {
|
|
// check for null first to give the most precise exception.
|
|
Objects.requireNonNull(obj, message);
|
|
if (isEmpty(obj)) {
|
|
throw new IllegalArgumentException(message);
|
|
}
|
|
return obj;
|
|
}
|
|
|
|
// ToString
|
|
// -----------------------------------------------------------------------
|
|
/**
|
|
* <p>
|
|
* Gets the {@code toString} of an {@code Object} returning an empty string ("")
|
|
* if {@code null} input.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.toString(null) = ""
|
|
* ObjectUtils.toString("") = ""
|
|
* ObjectUtils.toString("bat") = "bat"
|
|
* ObjectUtils.toString(Boolean.TRUE) = "true"
|
|
* </pre>
|
|
*
|
|
* @see StringUtils#defaultString(String)
|
|
* @see String#valueOf(Object)
|
|
* @param obj the Object to {@code toString}, may be null
|
|
* @return the passed in Object's toString, or {@code ""} if {@code null} input
|
|
* @since 2.0
|
|
* @deprecated this method has been replaced by
|
|
* {@code java.util.Objects.toString(Object)} in Java 7 and will be
|
|
* removed in future releases. Note however that said method will
|
|
* return "null" for null references, while this method returns an
|
|
* empty String. To preserve behavior use
|
|
* {@code java.util.Objects.toString(myObject, "")}
|
|
*/
|
|
@Deprecated
|
|
public static String toString(final Object obj) {
|
|
return obj == null ? StringUtils.EMPTY : obj.toString();
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Gets the {@code toString} of an {@code Object} returning a specified text if
|
|
* {@code null} input.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.toString(null, null) = null
|
|
* ObjectUtils.toString(null, "null") = "null"
|
|
* ObjectUtils.toString("", "null") = ""
|
|
* ObjectUtils.toString("bat", "null") = "bat"
|
|
* ObjectUtils.toString(Boolean.TRUE, "null") = "true"
|
|
* </pre>
|
|
*
|
|
* @see StringUtils#defaultString(String,String)
|
|
* @see String#valueOf(Object)
|
|
* @param obj the Object to {@code toString}, may be null
|
|
* @param nullStr the String to return if {@code null} input, may be null
|
|
* @return the passed in Object's toString, or {@code nullStr} if {@code null}
|
|
* input
|
|
* @since 2.0
|
|
* @deprecated this method has been replaced by
|
|
* {@code java.util.Objects.toString(Object, String)} in Java 7 and
|
|
* will be removed in future releases.
|
|
*/
|
|
@Deprecated
|
|
public static String toString(final Object obj, final String nullStr) {
|
|
return obj == null ? nullStr : obj.toString();
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Gets the {@code toString} of an {@code Object} returning a specified text if
|
|
* {@code null} input.
|
|
* </p>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.toString(obj, () -> expensive())
|
|
* </pre>
|
|
*
|
|
* <pre>
|
|
* ObjectUtils.toString(null, () -> expensive()) = result of expensive()
|
|
* ObjectUtils.toString(null, () -> expensive()) = result of expensive()
|
|
* ObjectUtils.toString("", () -> expensive()) = ""
|
|
* ObjectUtils.toString("bat", () -> expensive()) = "bat"
|
|
* ObjectUtils.toString(Boolean.TRUE, () -> expensive()) = "true"
|
|
* </pre>
|
|
*
|
|
* @param obj the Object to {@code toString}, may be null
|
|
* @param supplier the Supplier of String used on {@code null} input, may be
|
|
* null
|
|
* @return the passed in Object's toString, or {@code nullStr} if {@code null}
|
|
* input
|
|
* @since 3.11
|
|
*/
|
|
public static String toString(final Object obj, final Supplier<String> supplier) {
|
|
return obj == null ? supplier == null ? null : supplier.get() : obj.toString();
|
|
}
|
|
|
|
/**
|
|
* Calls {@link Object#wait(long, int)} for the given Duration.
|
|
*
|
|
* @param obj The receiver of the wait call.
|
|
* @param duration How long to wait.
|
|
* @throws IllegalArgumentException if the timeout duration is negative.
|
|
* @throws IllegalMonitorStateException if the current thread is not the owner
|
|
* of the {@code obj}'s monitor.
|
|
* @throws InterruptedException if any thread interrupted the current
|
|
* thread before or while the current
|
|
* thread was waiting for a notification.
|
|
* The <em>interrupted status</em> of the
|
|
* current thread is cleared when this
|
|
* exception is thrown.
|
|
* @see Object#wait(long, int)
|
|
* @since 3.12.0
|
|
*/
|
|
public static void wait(final Object obj, final Duration duration) throws InterruptedException {
|
|
DurationUtils.accept(obj::wait, DurationUtils.zeroIfNull(duration));
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* {@code ObjectUtils} instances should NOT be constructed in standard
|
|
* programming. Instead, the static methods on the class should be used, such as
|
|
* {@code ObjectUtils.defaultIfNull("a","b");}.
|
|
* </p>
|
|
*
|
|
* <p>
|
|
* This constructor is public to permit tools that require a JavaBean instance
|
|
* to operate.
|
|
* </p>
|
|
*/
|
|
public ObjectUtils() {
|
|
}
|
|
|
|
}
|