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A bundle project producing JAX-RS RI bundles. The primary artifact is an "all-in-one" OSGi-fied JAX-RS RI bundle
(jaxrs-ri.jar).
Attached to that are two compressed JAX-RS RI archives. The first archive (jaxrs-ri.zip) consists of binary RI bits and
contains the API jar (under "api" directory), RI libraries (under "lib" directory) as well as all external
RI dependencies (under "ext" directory). The secondary archive (jaxrs-ri-src.zip) contains buildable JAX-RS RI source
bundle and contains the API jar (under "api" directory), RI sources (under "src" directory) as well as all external
RI dependencies (under "ext" directory). The second archive also contains "build.xml" ANT script that builds the RI
sources. To build the JAX-RS RI simply unzip the archive, cd to the created jaxrs-ri directory and invoke "ant" from
the command line.
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*
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*
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* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* http://glassfish.java.net/public/CDDL+GPL_1_1.html
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* language governing permissions and limitations under the License.
*
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* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
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* exception as provided by Oracle in the GPL Version 2 section of the License
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*
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*/
package org.glassfish.jersey.internal.util.collection;
/**
* A collection of {@link Value Value provider} factory & utility methods.
*
* @author Marek Potociar (marek.potociar at oracle.com)
*/
public final class Values {
private static final LazyValue EMPTY = new LazyValue() {
@Override
public Object get() {
return null;
}
@Override
public boolean isInitialized() {
return true;
}
};
private static final LazyUnsafeValue EMPTY_UNSAFE = new LazyUnsafeValue() {
@Override
public Object get() {
return null;
}
@Override
public boolean isInitialized() {
return true;
}
};
private Values() {
// prevents instantiation.
}
/**
* Get an empty {@link Value value provider} whose {@link Value#get() get()}
* method always returns {@code null}.
*
* @param value type.
* @return empty value provider.
*/
public static Value empty() {
//noinspection unchecked
return (Value) EMPTY;
}
/**
* Get an empty {@link UnsafeValue value provider} whose {@link UnsafeValue#get() get()}
* method always returns {@code null}.
*
* @param value type.
* @return empty unsafe value provider.
*/
public static UnsafeValue emptyUnsafe() {
//noinspection unchecked
return (UnsafeValue) EMPTY_UNSAFE;
}
/**
* Get a new constant {@link Value value provider} whose {@link Value#get() get()}
* method always returns the instance supplied to the {@code value} parameter.
*
* In case the supplied value constant is {@code null}, an {@link #empty() empty} value
* provider is returned.
*
* @param value type.
* @param value value instance to be provided.
* @return constant value provider.
*/
public static Value of(final T value) {
return (value == null) ? Values.empty() : new InstanceValue(value);
}
private static class InstanceValue implements Value {
private final T value;
public InstanceValue(final T value) {
this.value = value;
}
@Override
public T get() {
return value;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
return value.equals(((InstanceValue) o).value);
}
@Override
public int hashCode() {
return value != null ? value.hashCode() : 0;
}
@Override
public String toString() {
return "InstanceValue{value=" + value + '}';
}
}
/**
* Get a new constant {@link UnsafeValue value provider} whose {@link UnsafeValue#get() get()}
* method always returns the instance supplied to the {@code value} parameter.
*
* In case the supplied value constant is {@code null}, an {@link #emptyUnsafe() empty} value
* provider is returned.
*
* @param value type.
* @param value value instance to be provided.
* @return constant value provider.
*/
public static UnsafeValue unsafe(final T value) {
return (value == null) ? Values.emptyUnsafe() : new InstanceUnsafeValue(value);
}
private static class InstanceUnsafeValue implements UnsafeValue {
private final T value;
public InstanceUnsafeValue(final T value) {
this.value = value;
}
@Override
public T get() {
return value;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
return value.equals(((InstanceUnsafeValue) o).value);
}
@Override
public int hashCode() {
return value != null ? value.hashCode() : 0;
}
@Override
public String toString() {
return "InstanceUnsafeValue{value=" + value + '}';
}
}
/**
* Get a new "throwing" {@link UnsafeValue unsafe value provider} whose {@link UnsafeValue#get() get()}
* method always throws the exception supplied to the {@code throwable} parameter.
*
* In case the supplied throwable is {@code null}, an {@link NullPointerException} is thrown.
*
* @param value type.
* @param exception type.
* @param throwable throwable instance to be thrown.
* @return "throwing" unsafe value provider.
* @throws NullPointerException in case the supplied throwable instance is {@code null}.
*/
public static UnsafeValue throwing(final E throwable) {
if (throwable == null) {
throw new NullPointerException("Supplied throwable ");
}
return new ExceptionValue(throwable);
}
private static class ExceptionValue implements UnsafeValue {
private final E throwable;
public ExceptionValue(final E throwable) {
this.throwable = throwable;
}
@Override
public T get() throws E {
throw throwable;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
return throwable.equals(((ExceptionValue) o).throwable);
}
@Override
public int hashCode() {
return throwable != null ? throwable.hashCode() : 0;
}
@Override
public String toString() {
return "ExceptionValue{throwable=" + throwable + '}';
}
}
/**
* Get a new lazily initialized {@link Value value provider}.
*
* The value returned by its {@link Value#get() get()} method is lazily retrieved during a first
* call to the method from the supplied {@code delegate} value provider and is then cached for
* a subsequent retrieval.
*
* The implementation of the returned lazy value provider is thread-safe and is guaranteed to
* invoke the {@code get()} method on the supplied {@code delegate} value provider instance at
* most once.
*
*
* If the supplied value provider is {@code null}, an {@link #empty() empty} value
* provider is returned.
*
*
* @param value type.
* @param delegate value provider delegate that will be used to lazily initialize the value provider.
* @return lazily initialized value provider.
*/
public static LazyValue lazy(final Value delegate) {
//noinspection unchecked
return (delegate == null) ? (LazyValue) EMPTY : new LazyValueImpl(delegate);
}
/**
* Get a new eagerly initialized {@link Value value provider}.
*
* The value returned by its {@link Value#get() get()} method is eagerly computed from the supplied
* {@code delegate} value provider and is then stored in a final field for a subsequent retrieval.
*
* The implementation of the returned eager value provider is thread-safe and is guaranteed to
* invoke the {@code get()} method on the supplied {@code delegate} value provider instance once
* and only once.
*
*
* If the supplied value provider is {@code null}, an {@link #empty() empty} value
* provider is returned.
*
*
* @param value type.
* @param delegate value provider delegate that will be used to eagerly initialize the value provider.
* @return eagerly initialized, constant value provider.
*/
public static Value eager(final Value delegate) {
return (delegate == null) ? Values.empty() : new EagerValue(delegate);
}
private static class EagerValue implements Value {
private final T result;
private EagerValue(Value value) {
this.result = value.get();
}
@Override
public T get() {
return result;
}
}
private static class LazyValueImpl implements LazyValue {
private final Object lock;
private final Value delegate;
private volatile Value value;
public LazyValueImpl(final Value delegate) {
this.delegate = delegate;
this.lock = new Object();
}
@Override
public T get() {
Value result = value;
if (result == null) {
synchronized (lock) {
result = value;
if (result == null) {
value = result = Values.of(delegate.get());
}
}
}
return result.get();
}
@Override
public boolean isInitialized() {
return value != null;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
return delegate.equals(((LazyValueImpl) o).delegate);
}
@Override
public int hashCode() {
return delegate != null ? delegate.hashCode() : 0;
}
@Override
public String toString() {
return "LazyValue{delegate=" + delegate.toString() + '}';
}
}
/**
* Get a new lazily initialized {@link UnsafeValue unsafe value provider}.
*
* The value returned by its {@link UnsafeValue#get() get()} method is lazily retrieved during a first
* call to the method from the supplied {@code delegate} value provider and is then cached for
* a subsequent retrieval.
*
* In case the call to underlying {@code delegate.get()} throws a throwable, the throwable is cached
* and thrown on all subsequent retrievals.
*
*
* The implementation of the returned lazy value provider is thread-safe and is guaranteed to
* invoke the {@code get()} method on the supplied {@code delegate} value provider instance at
* most once.
*
*
* If the supplied value provider is {@code null}, an {@link #empty() empty} value
* provider is returned.
*
*
* @param value type.
* @param delegate value provider delegate that will be used to lazily initialize the value provider.
* @return lazily initialized value provider.
*/
public static LazyUnsafeValue lazy(final UnsafeValue delegate) {
//noinspection unchecked
return (delegate == null) ? (LazyUnsafeValue) EMPTY_UNSAFE : new LazyUnsafeValueImpl(delegate);
}
private static class LazyUnsafeValueImpl implements LazyUnsafeValue {
private final Object lock;
private final UnsafeValue delegate;
private volatile UnsafeValue value;
public LazyUnsafeValueImpl(final UnsafeValue delegate) {
this.delegate = delegate;
this.lock = new Object();
}
@Override
public T get() throws E {
UnsafeValue result = value;
if (result == null) {
synchronized (lock) {
result = value;
//noinspection ConstantConditions
if (result == null) {
try {
result = Values.unsafe(delegate.get());
} catch (Throwable e) {
//noinspection unchecked
result = Values.throwing((E) e);
}
value = result;
}
}
}
return result.get();
}
@Override
public boolean isInitialized() {
return value != null;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
return delegate.equals(((LazyUnsafeValueImpl) o).delegate);
}
@Override
public int hashCode() {
return delegate != null ? delegate.hashCode() : 0;
}
@Override
public String toString() {
return "LazyValue{delegate=" + delegate.toString() + '}';
}
}
}