From a074906ea7d72d94db0573920d50a896e0f38c0e Mon Sep 17 00:00:00 2001
From: Alexey Andreev <konsoletyper@gmail.com>
Date: Tue, 14 Apr 2020 09:25:20 +0300
Subject: [PATCH] Implement AtomicReference

---
 .../concurrent/atomic/TAtomicReference.java   | 164 ++++++++++++++++++
 1 file changed, 164 insertions(+)
 create mode 100644 classlib/src/main/java/org/teavm/classlib/java/util/concurrent/atomic/TAtomicReference.java

diff --git a/classlib/src/main/java/org/teavm/classlib/java/util/concurrent/atomic/TAtomicReference.java b/classlib/src/main/java/org/teavm/classlib/java/util/concurrent/atomic/TAtomicReference.java
new file mode 100644
index 000000000..8f71b93d3
--- /dev/null
+++ b/classlib/src/main/java/org/teavm/classlib/java/util/concurrent/atomic/TAtomicReference.java
@@ -0,0 +1,164 @@
+/*
+ *  Copyright 2020 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.classlib.java.util.concurrent.atomic;
+
+import java.io.Serializable;
+import java.util.function.BinaryOperator;
+import java.util.function.LongBinaryOperator;
+import java.util.function.LongUnaryOperator;
+import java.util.function.UnaryOperator;
+
+@SuppressWarnings("NonAtomicOperationOnVolatileField")
+public class TAtomicReference<V> implements Serializable {
+    private V value;
+    private volatile int version;
+
+    public TAtomicReference() {
+    }
+
+    public TAtomicReference(V value) {
+        this.value = value;
+    }
+
+    public final V get() {
+        return value;
+    }
+
+    public final void set(V newValue) {
+        value = newValue;
+        version++;
+    }
+
+    public final void lazySet(V newValue) {
+        value = newValue;
+        version++;
+    }
+
+    public final V getAndSet(V newValue) {
+        V result = value;
+        value = newValue;
+        version++;
+        return result;
+    }
+
+    public final boolean compareAndSet(V expect, V update) {
+        if (value != expect) {
+            return false;
+        }
+        value = update;
+        version++;
+        return true;
+    }
+
+    public final boolean weakCompareAndSet(V expect, V update) {
+        if (value != expect) {
+            return false;
+        }
+        value = update;
+        version++;
+        return true;
+    }
+
+    public final V getAndUpdate(UnaryOperator<V> updateFunction) {
+        int expectedVersion;
+        V result;
+        V newValue;
+        do {
+            expectedVersion = version;
+            result = value;
+            newValue = updateFunction.apply(value);
+        } while (expectedVersion != version);
+        ++version;
+        value = newValue;
+        return result;
+    }
+
+    public final V updateAndGet(UnaryOperator<V> updateFunction) {
+        int expectedVersion;
+        V newValue;
+        do {
+            expectedVersion = version;
+            newValue = updateFunction.apply(value);
+        } while (expectedVersion != version);
+        ++version;
+        value = newValue;
+        return newValue;
+    }
+
+    public final V getAndAccumulate(V x, BinaryOperator<V> accumulatorFunction) {
+        int expectedVersion;
+        V newValue;
+        V result;
+        do {
+            expectedVersion = version;
+            result = value;
+            newValue = accumulatorFunction.apply(value, x);
+        } while (expectedVersion != version);
+        ++version;
+        value = newValue;
+        return result;
+    }
+
+    public final V accumulateAndGet(V x, BinaryOperator<V> accumulatorFunction) {
+        int expectedVersion;
+        V newValue;
+        do {
+            expectedVersion = version;
+            newValue = accumulatorFunction.apply(value, x);
+        } while (expectedVersion != version);
+        ++version;
+        value = newValue;
+        return newValue;
+    }
+
+    @Override
+    public String toString() {
+        return String.valueOf(value);
+    }
+
+    public final V getPlain() {
+        return value;
+    }
+
+    public final void setPlain(V value) {
+        this.value = value;
+    }
+
+    public final V getOpaque() {
+        return value;
+    }
+
+    public final void setOpaque(V value) {
+        this.value = value;
+    }
+
+    public final V getAcquire() {
+        return value;
+    }
+
+    public final void setRelease(V value) {
+        this.value = value;
+    }
+
+    public final V compareAndExchange(V expectedValue, V newValue) {
+        if (value == expectedValue) {
+            value = newValue;
+            return expectedValue;
+        } else {
+            return value;
+        }
+    }
+}