diff --git a/classlib/src/main/java/org/teavm/classlib/java/util/TOptional.java b/classlib/src/main/java/org/teavm/classlib/java/util/TOptional.java
index a0f472e67..6da3e41ae 100644
--- a/classlib/src/main/java/org/teavm/classlib/java/util/TOptional.java
+++ b/classlib/src/main/java/org/teavm/classlib/java/util/TOptional.java
@@ -15,6 +15,7 @@
  */
 package org.teavm.classlib.java.util;
 
+import java.util.NoSuchElementException;
 import java.util.Objects;
 import java.util.function.Consumer;
 import java.util.function.Function;
@@ -90,6 +91,15 @@ public final class TOptional<T> {
         return value != null ? mapper.apply(value) : (TOptional<U>) this;
     }
 
+    @SuppressWarnings("unchecked")
+    public TOptional<T> or(Supplier<? extends TOptional<? extends T>> supplier) {
+        if (value != null) {
+            return this;
+        } else {
+            return Objects.requireNonNull((TOptional<T>) supplier.get());
+        }
+    }
+
     public T orElse(T other) {
         return value != null ? value : other;
     }
@@ -98,6 +108,14 @@ public final class TOptional<T> {
         return value != null ? value : other.get();
     }
 
+    public void ifPresentOrElse(Consumer<? super T> action, Runnable emptyAction) {
+        if (value != null) {
+            action.accept(value);
+        } else {
+            emptyAction.run();
+        }
+    }
+
     public <X extends Throwable> T orElseThrow(Supplier<? extends X> exceptionSupplier) throws X {
         if (value == null) {
             throw exceptionSupplier.get();
@@ -105,6 +123,13 @@ public final class TOptional<T> {
         return value;
     }
 
+    public T orElseThrow() {
+        if (value == null) {
+            throw new NoSuchElementException();
+        }
+        return value;
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) {
diff --git a/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalDouble.java b/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalDouble.java
index 82b04a6bc..2d7434186 100644
--- a/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalDouble.java
+++ b/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalDouble.java
@@ -19,6 +19,7 @@ import java.util.NoSuchElementException;
 import java.util.function.DoubleConsumer;
 import java.util.function.DoubleSupplier;
 import java.util.function.Supplier;
+import org.teavm.classlib.java.util.stream.TDoubleStream;
 
 public class TOptionalDouble {
     private static TOptionalDouble emptyInstance;
@@ -51,6 +52,10 @@ public class TOptionalDouble {
         return this != emptyInstance;
     }
 
+    public boolean isEmpty() {
+        return this == emptyInstance;
+    }
+
     public void ifPresent(DoubleConsumer consumer) {
         if (this != emptyInstance) {
             consumer.accept(value);
@@ -65,19 +70,42 @@ public class TOptionalDouble {
         return this != emptyInstance ? value : other.getAsDouble();
     }
 
+    public void ifPresentOrElse(DoubleConsumer action, Runnable emptyAction) {
+        if (this == emptyInstance) {
+            emptyAction.run();
+        } else {
+            action.accept(value);
+        }
+    }
+
     public <X extends Throwable> double orElseThrow(Supplier<? extends X> exceptionSupplier) throws X {
-        if (!isPresent()) {
+        if (this == emptyInstance) {
             throw exceptionSupplier.get();
         }
         return value;
     }
 
+    public double orElseThrow() {
+        if (this == emptyInstance) {
+            throw new NoSuchElementException();
+        }
+        return value;
+    }
+
+    public TDoubleStream stream() {
+        if (this == emptyInstance) {
+            return TDoubleStream.empty();
+        } else {
+            return TDoubleStream.of(value);
+        }
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) {
             return true;
         }
-        if (!(obj instanceof TOptionalDouble)) {
+        if (this == emptyInstance || obj == emptyInstance || !(obj instanceof TOptionalDouble)) {
             return false;
         }
 
diff --git a/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalInt.java b/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalInt.java
index 4f92ef5ec..738f716cb 100644
--- a/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalInt.java
+++ b/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalInt.java
@@ -19,6 +19,7 @@ import java.util.NoSuchElementException;
 import java.util.function.IntConsumer;
 import java.util.function.IntSupplier;
 import java.util.function.Supplier;
+import org.teavm.classlib.java.util.stream.TIntStream;
 
 public class TOptionalInt {
     private static TOptionalInt emptyInstance;
@@ -51,6 +52,10 @@ public class TOptionalInt {
         return this != emptyInstance;
     }
 
+    public boolean isEmpty() {
+        return this == emptyInstance;
+    }
+
     public void ifPresent(IntConsumer consumer) {
         if (this != emptyInstance) {
             consumer.accept(value);
@@ -65,19 +70,42 @@ public class TOptionalInt {
         return this != emptyInstance ? value : other.getAsInt();
     }
 
+    public void ifPresentOrElse(IntConsumer action, Runnable emptyAction) {
+        if (this == emptyInstance) {
+            emptyAction.run();
+        } else {
+            action.accept(value);
+        }
+    }
+
     public <X extends Throwable> int orElseThrow(Supplier<? extends X> exceptionSupplier) throws X {
-        if (!isPresent()) {
+        if (this == emptyInstance) {
             throw exceptionSupplier.get();
         }
         return value;
     }
 
+    public int orElseThrow() {
+        if (this == emptyInstance) {
+            throw new NoSuchElementException();
+        }
+        return value;
+    }
+
+    public TIntStream stream() {
+        if (this == emptyInstance) {
+            return TIntStream.empty();
+        } else {
+            return TIntStream.of(value);
+        }
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) {
             return true;
         }
-        if (!(obj instanceof TOptionalInt)) {
+        if (this == emptyInstance || obj == emptyInstance || !(obj instanceof TOptionalInt)) {
             return false;
         }
 
diff --git a/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalLong.java b/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalLong.java
index a6f7d58d5..957527ef1 100644
--- a/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalLong.java
+++ b/classlib/src/main/java/org/teavm/classlib/java/util/TOptionalLong.java
@@ -19,6 +19,7 @@ import java.util.NoSuchElementException;
 import java.util.function.LongConsumer;
 import java.util.function.LongSupplier;
 import java.util.function.Supplier;
+import org.teavm.classlib.java.util.stream.TLongStream;
 
 public class TOptionalLong {
     private static TOptionalLong emptyInstance;
@@ -51,6 +52,10 @@ public class TOptionalLong {
         return this != emptyInstance;
     }
 
+    public boolean isEmpty() {
+        return this == emptyInstance;
+    }
+
     public void ifPresent(LongConsumer consumer) {
         if (this != emptyInstance) {
             consumer.accept(value);
@@ -65,19 +70,42 @@ public class TOptionalLong {
         return this != emptyInstance ? value : other.getAsLong();
     }
 
+    public void ifPresentOrElse(LongConsumer action, Runnable emptyAction) {
+        if (this == emptyInstance) {
+            emptyAction.run();
+        } else {
+            action.accept(value);
+        }
+    }
+
     public <X extends Throwable> long orElseThrow(Supplier<? extends X> exceptionSupplier) throws X {
-        if (!isPresent()) {
+        if (this == emptyInstance) {
             throw exceptionSupplier.get();
         }
         return value;
     }
 
+    public long orElseThrow() {
+        if (this == emptyInstance) {
+            throw new NoSuchElementException();
+        }
+        return value;
+    }
+
+    public TLongStream stream() {
+        if (this == emptyInstance) {
+            return TLongStream.empty();
+        } else {
+            return TLongStream.of(value);
+        }
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) {
             return true;
         }
-        if (!(obj instanceof TOptionalLong)) {
+        if (this == emptyInstance || obj == emptyInstance || !(obj instanceof TOptionalLong)) {
             return false;
         }