OpenJDK / jdk-updates / jdk12u
changeset 16489:53619efef3fb
8001642: Add Optional<T>, OptionalDouble, OptionalInt, OptionalLong
Reviewed-by: mduigou, darcy, alanb, jjb
Contributed-by: Brian Goetz <brian.goetz@oracle.com>
author | mduigou |
---|---|
date | Tue, 19 Mar 2013 16:05:34 -0700 |
parents | 816b9df68a9f |
children | 43315ae7fa96 |
files | jdk/src/share/classes/java/util/Optional.java jdk/src/share/classes/java/util/OptionalDouble.java jdk/src/share/classes/java/util/OptionalInt.java jdk/src/share/classes/java/util/OptionalLong.java jdk/test/java/util/Optional/Basic.java jdk/test/java/util/Optional/BasicDouble.java jdk/test/java/util/Optional/BasicInt.java jdk/test/java/util/Optional/BasicLong.java |
diffstat | 8 files changed, 1445 insertions(+), 0 deletions(-) [+] |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/share/classes/java/util/Optional.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,243 @@ +/* + * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ +package java.util; + +import java.util.function.Consumer; +import java.util.function.Supplier; + +/** + * A container object which may or may not contain a non-null value. + * If a value is present, {@code isPresent()} will return {@code true} and + * {@code get()} will return the value. + * + * <p>Additional methods that depend on the presence or absence of a contained + * value are provided, such as {@link #orElse(java.lang.Object) orElse()} + * (return a default value if value not present) and + * {@link #ifPresent(java.util.function.Consumer) ifPresent()} (execute a block + * of code if the value is present). + * + * @since 1.8 + */ +public final class Optional<T> { + /** + * Common instance for {@code empty()}. + */ + private static final Optional<?> EMPTY = new Optional<>(); + + /** + * If non-null, the value; if null, indicates no value is present + */ + private final T value; + + /** + * Construct an empty instance. + * + * @implNote Generally only one empty instance, {@link Optional#EMPTY}, + * should exist per VM. + */ + private Optional() { + this.value = null; + } + + /** + * Returns an empty {@code Optional} instance. No value is present for this + * Optional. + * + * @apiNote Though it may be tempting to do so, avoid testing if an object + * is empty by comparing with {@code ==} against instances returned by + * {@code Option.empty()}. There is no guarantee that it is a singleton. + * Instead, use {@link #isPresent()}. + * + * @param <T> Type of the non-existent value + * @return an empty {@code Optional} + */ + public static<T> Optional<T> empty() { + @SuppressWarnings("unchecked") + Optional<T> t = (Optional<T>) EMPTY; + return t; + } + + /** + * Construct an instance with the value present. + * + * @param value the non-null value to be present + */ + private Optional(T value) { + this.value = Objects.requireNonNull(value); + } + + /** + * Return an {@code Optional} with the specified present value. + * + * @param value the value to be present, which must be non-null + * @return an {@code Optional} with the value present + */ + public static <T> Optional<T> of(T value) { + return new Optional<>(value); + } + + /** + * If a value is present in this {@code Optional}, returns the value, + * otherwise throws {@code NoSuchElementException}. + * + * @return the non-null value held by this {@code Optional} + * @throws NoSuchElementException if there is no value present + * + * @see Optional#isPresent() + */ + public T get() { + if (value == null) { + throw new NoSuchElementException("No value present"); + } + return value; + } + + /** + * Return {@code true} if there is a value present, otherwise {@code false}. + * + * @return {@code true} if there is a value present, otherwise {@code false} + */ + public boolean isPresent() { + return value != null; + } + + /** + * Have the specified consumer accept the value if a value is present, + * otherwise do nothing. + * + * @param consumer block to be executed if a value is present + * @throws NullPointerException if value is present and {@code consumer} is + * null + */ + public void ifPresent(Consumer<? super T> consumer) { + if (value != null) + consumer.accept(value); + } + + /** + * Return the value if present, otherwise return {@code other}. + * + * @param other the value to be returned if there is no value present, may + * be null + * @return the value, if present, otherwise {@code other} + */ + public T orElse(T other) { + return value != null ? value : other; + } + + /** + * Return the value if present, otherwise invoke {@code other} and return + * the result of that invocation. + * + * @param other a {@code Supplier} whose result is returned if no value + * is present + * @return the value if present otherwise the result of {@code other.get()} + * @throws NullPointerException if value is not present and {@code other} is + * null + */ + public T orElseGet(Supplier<? extends T> other) { + return value != null ? value : other.get(); + } + + /** + * Return the contained value, if present, otherwise throw an exception + * to be created by the provided supplier. + * + * @apiNote A method reference to the exception constructor with an empty + * argument list can be used as the supplier. For example, + * {@code IllegalStateException::new} + * + * @param <X> Type of the exception to be thrown + * @param exceptionSupplier The supplier which will return the exception to + * be thrown + * @return the present value + * @throws X if there is no value present + * @throws NullPointerException if no value is present and + * {@code exceptionSupplier} is null + */ + public <X extends Throwable> T orElseThrow(Supplier<? extends X> exceptionSupplier) throws X { + if (value != null) { + return value; + } else { + throw exceptionSupplier.get(); + } + } + + /** + * Indicates whether some other object is "equal to" this Optional. The + * other object is considered equal if: + * <ul> + * <li>it is also an {@code Optional} and; + * <li>both instances have no value present or; + * <li>the present values are "equal to" each other via {@code equals()}. + * </ul> + * + * @param obj an object to be tested for equality + * @return {code true} if the other object is "equal to" this object + * otherwise {@code false} + */ + @Override + public boolean equals(Object obj) { + if (this == obj) { + return true; + } + + if (!(obj instanceof Optional)) { + return false; + } + + Optional other = (Optional) obj; + return Objects.equals(value, other.value); + } + + /** + * Returns the hash code value of the present value, if any, or 0 (zero) if + * no value is present. + * + * @return hash code value of the present value or 0 if no value is present + */ + @Override + public int hashCode() { + return Objects.hashCode(value); + } + + /** + * Returns a non-empty string representation of this Optional suitable for + * debugging. The exact presentation format is unspecified and may vary + * between implementations and versions. + * + * @implSpec If a value is present the result must include its string + * representation in the result. Empty and present Optionals must be + * unambiguously differentiable. + * + * @return the string representation of this instance + */ + @Override + public String toString() { + return value != null + ? String.format("Optional[%s]", value) + : "Optional.empty"; + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/share/classes/java/util/OptionalDouble.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,245 @@ +/* + * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ +package java.util; + +import java.util.function.DoubleConsumer; +import java.util.function.DoubleSupplier; +import java.util.function.Supplier; + +/** + * A container object which may or may not contain a {@code double} value. + * If a value is present, {@code isPresent()} will return {@code true} and + * {@code get()} will return the value. + * + * <p>Additional methods that depend on the presence or absence of a contained + * value are provided, such as {@link #orElse(double) orElse()} + * (return a default value if value not present) and + * {@link #ifPresent(java.util.function.DoubleConsumer) ifPresent()} (execute a block + * of code if the value is present). + * + * @since 1.8 + */ +public final class OptionalDouble { + /** + * Common instance for {@code empty()}. + */ + private static final OptionalDouble EMPTY = new OptionalDouble(); + + /** + * If true then the value is present, otherwise indicates no value is present + */ + private final boolean isPresent; + private final double value; + + /** + * Construct an empty instance. + * + * @implNote generally only one empty instance, {@link OptionalDouble#EMPTY}, + * should exist per VM. + */ + private OptionalDouble() { + this.isPresent = false; + this.value = Double.NaN; + } + + /** + * Returns an empty {@code OptionalDouble} instance. No value is present for this + * OptionalDouble. + * + * @apiNote Though it may be tempting to do so, avoid testing if an object + * is empty by comparing with {@code ==} against instances returned by + * {@code Option.empty()}. There is no guarantee that it is a singleton. + * Instead, use {@link #isPresent()}. + * + * @return an empty {@code OptionalDouble}. + */ + public static OptionalDouble empty() { + return EMPTY; + } + + /** + * Construct an instance with the value present. + * + * @param value the double value to be present. + */ + private OptionalDouble(double value) { + this.isPresent = true; + this.value = value; + } + + /** + * Return an {@code OptionalDouble} with the specified value present. + * + * @param value the value to be present + * @return an {@code OptionalDouble} with the value present + */ + public static OptionalDouble of(double value) { + return new OptionalDouble(value); + } + + /** + * If a value is present in this {@code OptionalDouble}, returns the value, + * otherwise throws {@code NoSuchElementException}. + * + * @return the value held by this {@code OptionalDouble} + * @throws NoSuchElementException if there is no value present + * + * @see OptionalDouble#isPresent() + */ + public double getAsDouble() { + if (!isPresent) { + throw new NoSuchElementException("No value present"); + } + return value; + } + + /** + * Return {@code true} if there is a value present, otherwise {@code false}. + * + * @return {@code true} if there is a value present, otherwise {@code false} + */ + public boolean isPresent() { + return isPresent; + } + + /** + * Have the specified consumer accept the value if a value is present, + * otherwise do nothing. + * + * @param consumer block to be executed if a value is present + * @throws NullPointerException if value is present and {@code consumer} is + * null + */ + public void ifPresent(DoubleConsumer consumer) { + if (isPresent) + consumer.accept(value); + } + + /** + * Return the value if present, otherwise return {@code other}. + * + * @param other the value to be returned if there is no value present + * @return the value, if present, otherwise {@code other} + */ + public double orElse(double other) { + return isPresent ? value : other; + } + + /** + * Return the value if present, otherwise invoke {@code other} and return + * the result of that invocation. + * + * @param other a {@code DoubleSupplier} whose result is returned if no value + * is present + * @return the value if present otherwise the result of {@code other.getAsDouble()} + * @throws NullPointerException if value is not present and {@code other} is + * null + */ + public double orElseGet(DoubleSupplier other) { + return isPresent ? value : other.getAsDouble(); + } + + /** + * Return the contained value, if present, otherwise throw an exception + * to be created by the provided supplier. + * + * @apiNote A method reference to the exception constructor with an empty + * argument list can be used as the supplier. For example, + * {@code IllegalStateException::new} + * + * @param <X> Type of the exception to be thrown + * @param exceptionSupplier The supplier which will return the exception to + * be thrown + * @return the present value + * @throws X if there is no value present + * @throws NullPointerException if no value is present and + * {@code exceptionSupplier} is null + */ + public<X extends Throwable> double orElseThrow(Supplier<X> exceptionSupplier) throws X { + if (isPresent) { + return value; + } else { + throw exceptionSupplier.get(); + } + } + + /** + * Indicates whether some other object is "equal to" this Optional. The + * other object is considered equal if: + * <ul> + * <li>it is also an {@code OptionalInt} and; + * <li>both instances have no value present or; + * <li>the present values are "equal to" each other via {@code Double.compare() == 0}. + * </ul> + * + * @param obj an object to be tested for equality + * @return {code true} if the other object is "equal to" this object + * otherwise {@code false} + */ + @Override + public boolean equals(Object obj) { + if (this == obj) { + return true; + } + + if (!(obj instanceof OptionalDouble)) { + return false; + } + + OptionalDouble other = (OptionalDouble) obj; + return (isPresent && other.isPresent) + ? Double.compare(value, other.value) == 0 + : isPresent == other.isPresent; + } + + /** + * Returns the hash code value of the present value, if any, or 0 (zero) if + * no value is present. + * + * @return hash code value of the present value or 0 if no value is present + */ + @Override + public int hashCode() { + return isPresent ? Double.hashCode(value) : 0; + } + + /** + * Returns a non-empty string representation of this OptionalDouble suitable for + * debugging. The exact presentation format is unspecified and may vary + * between implementations and versions. + * + * @implSpec If a value is present the result must include its string + * representation in the result. Empty and present OptionalDoubless must be + * unambiguously differentiable. + * + * @return the string representation of this instance + */ + @Override + public String toString() { + return isPresent + ? String.format("OptionalDouble[%s]", value) + : "OptionalDouble.empty"; + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/share/classes/java/util/OptionalInt.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,245 @@ +/* + * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ +package java.util; + +import java.util.function.IntConsumer; +import java.util.function.IntSupplier; +import java.util.function.Supplier; + +/** + * A container object which may or may not contain a {@code int} value. + * If a value is present, {@code isPresent()} will return {@code true} and + * {@code get()} will return the value. + * + * <p>Additional methods that depend on the presence or absence of a contained + * value are provided, such as {@link #orElse(int) orElse()} + * (return a default value if value not present) and + * {@link #ifPresent(java.util.function.IntConsumer) ifPresent()} (execute a block + * of code if the value is present). + * + * @since 1.8 + */ +public final class OptionalInt { + /** + * Common instance for {@code empty()}. + */ + private static final OptionalInt EMPTY = new OptionalInt(); + + /** + * If true then the value is present, otherwise indicates no value is present + */ + private final boolean isPresent; + private final int value; + + /** + * Construct an empty instance. + * + * @implNote Generally only one empty instance, {@link OptionalInt#EMPTY}, + * should exist per VM. + */ + private OptionalInt() { + this.isPresent = false; + this.value = 0; + } + + /** + * Returns an empty {@code OptionalInt} instance. No value is present for this + * OptionalInt. + * + * @apiNote Though it may be tempting to do so, avoid testing if an object + * is empty by comparing with {@code ==} against instances returned by + * {@code Option.empty()}. There is no guarantee that it is a singleton. + * Instead, use {@link #isPresent()}. + * + * @return an empty {@code OptionalInt} + */ + public static OptionalInt empty() { + return EMPTY; + } + + /** + * Construct an instance with the value present. + * + * @param value the int value to be present + */ + private OptionalInt(int value) { + this.isPresent = true; + this.value = value; + } + + /** + * Return an {@code OptionalInt} with the specified value present. + * + * @param value the value to be present + * @return an {@code OptionalInt} with the value present + */ + public static OptionalInt of(int value) { + return new OptionalInt(value); + } + + /** + * If a value is present in this {@code OptionalInt}, returns the value, + * otherwise throws {@code NoSuchElementException}. + * + * @return the value held by this {@code OptionalInt} + * @throws NoSuchElementException if there is no value present + * + * @see OptionalInt#isPresent() + */ + public int getAsInt() { + if (!isPresent) { + throw new NoSuchElementException("No value present"); + } + return value; + } + + /** + * Return {@code true} if there is a value present, otherwise {@code false}. + * + * @return {@code true} if there is a value present, otherwise {@code false} + */ + public boolean isPresent() { + return isPresent; + } + + /** + * Have the specified consumer accept the value if a value is present, + * otherwise do nothing. + * + * @param consumer block to be executed if a value is present + * @throws NullPointerException if value is present and {@code consumer} is + * null + */ + public void ifPresent(IntConsumer consumer) { + if (isPresent) + consumer.accept(value); + } + + /** + * Return the value if present, otherwise return {@code other}. + * + * @param other the value to be returned if there is no value present + * @return the value, if present, otherwise {@code other} + */ + public int orElse(int other) { + return isPresent ? value : other; + } + + /** + * Return the value if present, otherwise invoke {@code other} and return + * the result of that invocation. + * + * @param other a {@code IntSupplier} whose result is returned if no value + * is present + * @return the value if present otherwise the result of {@code other.getAsInt()} + * @throws NullPointerException if value is not present and {@code other} is + * null + */ + public int orElseGet(IntSupplier other) { + return isPresent ? value : other.getAsInt(); + } + + /** + * Return the contained value, if present, otherwise throw an exception + * to be created by the provided supplier. + * + * @apiNote A method reference to the exception constructor with an empty + * argument list can be used as the supplier. For example, + * {@code IllegalStateException::new} + * + * @param <X> Type of the exception to be thrown + * @param exceptionSupplier The supplier which will return the exception to + * be thrown + * @return the present value + * @throws X if there is no value present + * @throws NullPointerException if no value is present and + * {@code exceptionSupplier} is null + */ + public<X extends Throwable> int orElseThrow(Supplier<X> exceptionSupplier) throws X { + if (isPresent) { + return value; + } else { + throw exceptionSupplier.get(); + } + } + + /** + * Indicates whether some other object is "equal to" this Optional. The + * other object is considered equal if: + * <ul> + * <li>it is also an {@code OptionalInt} and; + * <li>both instances have no value present or; + * <li>the present values are "equal to" each other via {@code ==}. + * </ul> + * + * @param obj an object to be tested for equality + * @return {code true} if the other object is "equal to" this object + * otherwise {@code false} + */ + @Override + public boolean equals(Object obj) { + if (this == obj) { + return true; + } + + if (!(obj instanceof OptionalInt)) { + return false; + } + + OptionalInt other = (OptionalInt) obj; + return (isPresent && other.isPresent) + ? value == other.value + : isPresent == other.isPresent; + } + + /** + * Returns the hash code value of the present value, if any, or 0 (zero) if + * no value is present. + * + * @return hash code value of the present value or 0 if no value is present + */ + @Override + public int hashCode() { + return isPresent ? Integer.hashCode(value) : 0; + } + + /** + * Returns a non-empty string representation of this OptionalInt suitable for + * debugging. The exact presentation format is unspecified and may vary + * between implementations and versions. + * + * @implSpec If a value is present the result must include its string + * representation in the result. Empty and present OptionalInts must be + * unambiguously differentiable. + * + * @return the string representation of this instance + */ + @Override + public String toString() { + return isPresent + ? String.format("OptionalInt[%s]", value) + : "OptionalInt.empty"; + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/share/classes/java/util/OptionalLong.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,245 @@ +/* + * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ +package java.util; + +import java.util.function.LongConsumer; +import java.util.function.LongSupplier; +import java.util.function.Supplier; + +/** + * A container object which may or may not contain a {@code long} value. + * If a value is present, {@code isPresent()} will return {@code true} and + * {@code get()} will return the value. + * + * <p>Additional methods that depend on the presence or absence of a contained + * value are provided, such as {@link #orElse(long) orElse()} + * (return a default value if value not present) and + * {@link #ifPresent(java.util.function.LongConsumer) ifPresent()} (execute a block + * of code if the value is present). + * + * @since 1.8 + */ +public final class OptionalLong { + /** + * Common instance for {@code empty()}. + */ + private static final OptionalLong EMPTY = new OptionalLong(); + + /** + * If true then the value is present, otherwise indicates no value is present + */ + private final boolean isPresent; + private final long value; + + /** + * Construct an empty instance. + * + * @implNote generally only one empty instance, {@link OptionalLong#EMPTY}, + * should exist per VM. + */ + private OptionalLong() { + this.isPresent = false; + this.value = 0; + } + + /** + * Returns an empty {@code OptionalLong} instance. No value is present for this + * OptionalLong. + * + * @apiNote Though it may be tempting to do so, avoid testing if an object + * is empty by comparing with {@code ==} against instances returned by + * {@code Option.empty()}. There is no guarantee that it is a singleton. + * Instead, use {@link #isPresent()}. + * + * @return an empty {@code OptionalLong}. + */ + public static OptionalLong empty() { + return EMPTY; + } + + /** + * Construct an instance with the value present. + * + * @param value the long value to be present + */ + private OptionalLong(long value) { + this.isPresent = true; + this.value = value; + } + + /** + * Return an {@code OptionalLong} with the specified value present. + * + * @param value the value to be present + * @return an {@code OptionalLong} with the value present + */ + public static OptionalLong of(long value) { + return new OptionalLong(value); + } + + /** + * If a value is present in this {@code OptionalLong}, returns the value, + * otherwise throws {@code NoSuchElementException}. + * + * @return the value held by this {@code OptionalLong} + * @throws NoSuchElementException if there is no value present + * + * @see OptionalLong#isPresent() + */ + public long getAsLong() { + if (!isPresent) { + throw new NoSuchElementException("No value present"); + } + return value; + } + + /** + * Return {@code true} if there is a value present, otherwise {@code false}. + * + * @return {@code true} if there is a value present, otherwise {@code false} + */ + public boolean isPresent() { + return isPresent; + } + + /** + * Have the specified consumer accept the value if a value is present, + * otherwise do nothing. + * + * @param consumer block to be executed if a value is present + * @throws NullPointerException if value is present and {@code consumer} is + * null + */ + public void ifPresent(LongConsumer consumer) { + if (isPresent) + consumer.accept(value); + } + + /** + * Return the value if present, otherwise return {@code other}. + * + * @param other the value to be returned if there is no value present + * @return the value, if present, otherwise {@code other} + */ + public long orElse(long other) { + return isPresent ? value : other; + } + + /** + * Return the value if present, otherwise invoke {@code other} and return + * the result of that invocation. + * + * @param other a {@code LongSupplier} whose result is returned if no value + * is present + * @return the value if present otherwise the result of {@code other.getAsLong()} + * @throws NullPointerException if value is not present and {@code other} is + * null + */ + public long orElseGet(LongSupplier other) { + return isPresent ? value : other.getAsLong(); + } + + /** + * Return the contained value, if present, otherwise throw an exception + * to be created by the provided supplier. + * + * @apiNote A method reference to the exception constructor with an empty + * argument list can be used as the supplier. For example, + * {@code IllegalStateException::new} + * + * @param <X> Type of the exception to be thrown + * @param exceptionSupplier The supplier which will return the exception to + * be thrown + * @return the present value + * @throws X if there is no value present + * @throws NullPointerException if no value is present and + * {@code exceptionSupplier} is null + */ + public<X extends Throwable> long orElseThrow(Supplier<X> exceptionSupplier) throws X { + if (isPresent) { + return value; + } else { + throw exceptionSupplier.get(); + } + } + + /** + * Indicates whether some other object is "equal to" this Optional. The + * other object is considered equal if: + * <ul> + * <li>it is also an {@code OptionalInt} and; + * <li>both instances have no value present or; + * <li>the present values are "equal to" each other via {@code ==}. + * </ul> + * + * @param obj an object to be tested for equality + * @return {code true} if the other object is "equal to" this object + * otherwise {@code false} + */ + @Override + public boolean equals(Object obj) { + if (this == obj) { + return true; + } + + if (!(obj instanceof OptionalLong)) { + return false; + } + + OptionalLong other = (OptionalLong) obj; + return (isPresent && other.isPresent) + ? value == other.value + : isPresent == other.isPresent; + } + + /** + * Returns the hash code value of the present value, if any, or 0 (zero) if + * no value is present. + * + * @return hash code value of the present value or 0 if no value is present + */ + @Override + public int hashCode() { + return isPresent ? Long.hashCode(value) : 0; + } + + /** + * Returns a non-empty string representation of this OptionalLong suitable for + * debugging. The exact presentation format is unspecified and may vary + * between implementations and versions. + * + * @implSpec If a value is present the result must include its string + * representation in the result. Empty and present OptionalLongs must be + * unambiguously differentiable. + * + * @return the string representation of this instance + */ + @Override + public String toString() { + return isPresent + ? String.format("OptionalLong[%s]", value) + : "OptionalLong.empty"; + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/test/java/util/Optional/Basic.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,122 @@ +/* + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/* @test + * @summary Basic functional test of Optional + * @author Mike Duigou + * @run testng Basic + */ + +import java.util.NoSuchElementException; +import java.util.Optional; + +import static org.testng.Assert.*; +import org.testng.annotations.Test; + + +public class Basic { + + @Test(groups = "unit") + public void testEmpty() { + Optional<Boolean> empty = Optional.empty(); + Optional<String> presentEmptyString = Optional.of(""); + Optional<Boolean> present = Optional.of(Boolean.TRUE); + + // empty + assertTrue(empty.equals(empty)); + assertTrue(empty.equals(Optional.empty())); + assertTrue(!empty.equals(present)); + assertTrue(0 == empty.hashCode()); + assertTrue(!empty.toString().isEmpty()); + assertTrue(!empty.toString().equals(presentEmptyString.toString())); + assertTrue(!empty.isPresent()); + empty.ifPresent(v -> { fail(); }); + assertSame(null, empty.orElse(null)); + RuntimeException orElse = new RuntimeException() { }; + assertSame(Boolean.FALSE, empty.orElse(Boolean.FALSE)); + assertSame(null, empty.orElseGet(()-> null)); + assertSame(Boolean.FALSE, empty.orElseGet(()-> Boolean.FALSE)); + } + + @Test(expectedExceptions=NoSuchElementException.class) + public void testEmptyGet() { + Optional<Boolean> empty = Optional.empty(); + + Boolean got = empty.get(); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseGetNull() { + Optional<Boolean> empty = Optional.empty(); + + Boolean got = empty.orElseGet(null); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseThrowNull() throws Throwable { + Optional<Boolean> empty = Optional.empty(); + + Boolean got = empty.orElseThrow(null); + } + + @Test(expectedExceptions=ObscureException.class) + public void testEmptyOrElseThrow() throws Exception { + Optional<Boolean> empty = Optional.empty(); + + Boolean got = empty.orElseThrow(ObscureException::new); + } + + @Test(groups = "unit") + public void testPresent() { + Optional<Boolean> empty = Optional.empty(); + Optional<String> presentEmptyString = Optional.of(""); + Optional<Boolean> present = Optional.of(Boolean.TRUE); + + // present + assertTrue(present.equals(present)); + assertTrue(present.equals(Optional.of(Boolean.TRUE))); + assertTrue(!present.equals(empty)); + assertTrue(Boolean.TRUE.hashCode() == present.hashCode()); + assertTrue(!present.toString().isEmpty()); + assertTrue(!present.toString().equals(presentEmptyString.toString())); + assertTrue(-1 != present.toString().indexOf(Boolean.TRUE.toString())); + assertSame(Boolean.TRUE, present.get()); + try { + present.ifPresent(v -> { throw new ObscureException(); }); + fail(); + } catch(ObscureException expected) { + + } + assertSame(Boolean.TRUE, present.orElse(null)); + assertSame(Boolean.TRUE, present.orElse(Boolean.FALSE)); + assertSame(Boolean.TRUE, present.orElseGet(null)); + assertSame(Boolean.TRUE, present.orElseGet(()-> null)); + assertSame(Boolean.TRUE, present.orElseGet(()-> Boolean.FALSE)); + assertSame(Boolean.TRUE, present.<RuntimeException>orElseThrow( null)); + assertSame(Boolean.TRUE, present.<RuntimeException>orElseThrow(ObscureException::new)); + } + + private static class ObscureException extends RuntimeException { + + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/test/java/util/Optional/BasicDouble.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,115 @@ +/* + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2.0 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2.0 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2.0 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/* @test + * @summary Basic functional test of OptionalDouble + * @author Mike Duigou + * @run testng BasicDouble + */ + +import java.util.NoSuchElementException; +import java.util.OptionalDouble; + +import static org.testng.Assert.*; +import org.testng.annotations.Test; + + +public class BasicDouble { + + @Test(groups = "unit") + public void testEmpty() { + OptionalDouble empty = OptionalDouble.empty(); + OptionalDouble present = OptionalDouble.of(1.0); + + // empty + assertTrue(empty.equals(empty)); + assertTrue(empty.equals(OptionalDouble.empty())); + assertTrue(!empty.equals(present)); + assertTrue(0 == empty.hashCode()); + assertTrue(!empty.toString().isEmpty()); + assertTrue(!empty.isPresent()); + empty.ifPresent(v -> { fail(); }); + assertEquals(2.0, empty.orElse(2.0)); + assertEquals(2.0, empty.orElseGet(()-> 2.0)); + } + + @Test(expectedExceptions=NoSuchElementException.class) + public void testEmptyGet() { + OptionalDouble empty = OptionalDouble.empty(); + + double got = empty.getAsDouble(); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseGetNull() { + OptionalDouble empty = OptionalDouble.empty(); + + double got = empty.orElseGet(null); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseThrowNull() throws Throwable { + OptionalDouble empty = OptionalDouble.empty(); + + double got = empty.orElseThrow(null); + } + + @Test(expectedExceptions=ObscureException.class) + public void testEmptyOrElseThrow() throws Exception { + OptionalDouble empty = OptionalDouble.empty(); + + double got = empty.orElseThrow(ObscureException::new); + } + + @Test(groups = "unit") + public void testPresent() { + OptionalDouble empty = OptionalDouble.empty(); + OptionalDouble present = OptionalDouble.of(1.0); + + // present + assertTrue(present.equals(present)); + assertFalse(present.equals(OptionalDouble.of(0.0))); + assertTrue(present.equals(OptionalDouble.of(1.0))); + assertTrue(!present.equals(empty)); + assertTrue(Double.hashCode(1.0) == present.hashCode()); + assertFalse(present.toString().isEmpty()); + assertTrue(-1 != present.toString().indexOf(Double.toString(present.getAsDouble()).toString())); + assertEquals(1.0, present.getAsDouble()); + try { + present.ifPresent(v -> { throw new ObscureException(); }); + fail(); + } catch(ObscureException expected) { + + } + assertEquals(1.0, present.orElse(2.0)); + assertEquals(1.0, present.orElseGet(null)); + assertEquals(1.0, present.orElseGet(()-> 2.0)); + assertEquals(1.0, present.orElseGet(()-> 3.0)); + assertEquals(1.0, present.<RuntimeException>orElseThrow(null)); + assertEquals(1.0, present.<RuntimeException>orElseThrow(ObscureException::new)); + } + + private static class ObscureException extends RuntimeException { + + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/test/java/util/Optional/BasicInt.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,115 @@ +/* + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/* @test + * @summary Basic functional test of OptionalInt + * @author Mike Duigou + * @run testng BasicInt + */ + +import java.util.NoSuchElementException; +import java.util.OptionalInt; + +import static org.testng.Assert.*; +import org.testng.annotations.Test; + + +public class BasicInt { + + @Test(groups = "unit") + public void testEmpty() { + OptionalInt empty = OptionalInt.empty(); + OptionalInt present = OptionalInt.of(1); + + // empty + assertTrue(empty.equals(empty)); + assertTrue(empty.equals(OptionalInt.empty())); + assertTrue(!empty.equals(present)); + assertTrue(0 == empty.hashCode()); + assertTrue(!empty.toString().isEmpty()); + assertTrue(!empty.isPresent()); + empty.ifPresent(v -> { fail(); }); + assertEquals(2, empty.orElse(2)); + assertEquals(2, empty.orElseGet(()-> 2)); + } + + @Test(expectedExceptions=NoSuchElementException.class) + public void testEmptyGet() { + OptionalInt empty = OptionalInt.empty(); + + int got = empty.getAsInt(); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseGetNull() { + OptionalInt empty = OptionalInt.empty(); + + int got = empty.orElseGet(null); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseThrowNull() throws Throwable { + OptionalInt empty = OptionalInt.empty(); + + int got = empty.orElseThrow(null); + } + + @Test(expectedExceptions=ObscureException.class) + public void testEmptyOrElseThrow() throws Exception { + OptionalInt empty = OptionalInt.empty(); + + int got = empty.orElseThrow(ObscureException::new); + } + + @Test(groups = "unit") + public void testPresent() { + OptionalInt empty = OptionalInt.empty(); + OptionalInt present = OptionalInt.of(1); + + // present + assertTrue(present.equals(present)); + assertFalse(present.equals(OptionalInt.of(0))); + assertTrue(present.equals(OptionalInt.of(1))); + assertFalse(present.equals(empty)); + assertTrue(Integer.hashCode(1) == present.hashCode()); + assertFalse(present.toString().isEmpty()); + assertTrue(-1 != present.toString().indexOf(Integer.toString(present.getAsInt()).toString())); + assertEquals(1, present.getAsInt()); + try { + present.ifPresent(v -> { throw new ObscureException(); }); + fail(); + } catch(ObscureException expected) { + + } + assertEquals(1, present.orElse(2)); + assertEquals(1, present.orElseGet(null)); + assertEquals(1, present.orElseGet(()-> 2)); + assertEquals(1, present.orElseGet(()-> 3)); + assertEquals(1, present.<RuntimeException>orElseThrow(null)); + assertEquals(1, present.<RuntimeException>orElseThrow(ObscureException::new)); + } + + private static class ObscureException extends RuntimeException { + + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/test/java/util/Optional/BasicLong.java Tue Mar 19 16:05:34 2013 -0700 @@ -0,0 +1,115 @@ +/* + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/* @test + * @summary Basic functional test of OptionalLong + * @author Mike Duigou + * @run testng BasicLong + */ + +import java.util.NoSuchElementException; +import java.util.OptionalLong; + +import static org.testng.Assert.*; +import org.testng.annotations.Test; + + +public class BasicLong { + + @Test(groups = "unit") + public void testEmpty() { + OptionalLong empty = OptionalLong.empty(); + OptionalLong present = OptionalLong.of(1); + + // empty + assertTrue(empty.equals(empty)); + assertTrue(empty.equals(OptionalLong.empty())); + assertTrue(!empty.equals(present)); + assertTrue(0 == empty.hashCode()); + assertTrue(!empty.toString().isEmpty()); + assertTrue(!empty.isPresent()); + empty.ifPresent(v -> { fail(); }); + assertEquals(2, empty.orElse(2)); + assertEquals(2, empty.orElseGet(()-> 2)); + } + + @Test(expectedExceptions=NoSuchElementException.class) + public void testEmptyGet() { + OptionalLong empty = OptionalLong.empty(); + + long got = empty.getAsLong(); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseGetNull() { + OptionalLong empty = OptionalLong.empty(); + + long got = empty.orElseGet(null); + } + + @Test(expectedExceptions=NullPointerException.class) + public void testEmptyOrElseThrowNull() throws Throwable { + OptionalLong empty = OptionalLong.empty(); + + long got = empty.orElseThrow(null); + } + + @Test(expectedExceptions=ObscureException.class) + public void testEmptyOrElseThrow() throws Exception { + OptionalLong empty = OptionalLong.empty(); + + long got = empty.orElseThrow(ObscureException::new); + } + + @Test(groups = "unit") + public void testPresent() { + OptionalLong empty = OptionalLong.empty(); + OptionalLong present = OptionalLong.of(1L); + + // present + assertTrue(present.equals(present)); + assertFalse(present.equals(OptionalLong.of(0L))); + assertTrue(present.equals(OptionalLong.of(1L))); + assertFalse(present.equals(empty)); + assertTrue(Long.hashCode(1) == present.hashCode()); + assertFalse(present.toString().isEmpty()); + assertTrue(-1 != present.toString().indexOf(Long.toString(present.getAsLong()).toString())); + assertEquals(1L, present.getAsLong()); + try { + present.ifPresent(v -> { throw new ObscureException(); }); + fail(); + } catch(ObscureException expected) { + + } + assertEquals(1, present.orElse(2)); + assertEquals(1, present.orElseGet(null)); + assertEquals(1, present.orElseGet(()-> 2)); + assertEquals(1, present.orElseGet(()-> 3)); + assertEquals(1, present.<RuntimeException>orElseThrow(null)); + assertEquals(1, present.<RuntimeException>orElseThrow(ObscureException::new)); + } + + private static class ObscureException extends RuntimeException { + + } +}