MethodHandler.java
/*
* Copyright (c) 2012, 2019 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.jersey.server.model;
import java.lang.reflect.Constructor;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import javax.ws.rs.Encoded;
import org.glassfish.jersey.internal.inject.InjectionManager;
import org.glassfish.jersey.internal.inject.Injections;
/**
* Resource method handler model.
*
* @author Marek Potociar
*/
public abstract class MethodHandler implements ResourceModelComponent {
private final Collection<Parameter> handlerParameters;
/**
* Create new instance of a resource method handler model.
*/
protected MethodHandler() {
this.handlerParameters = Collections.emptyList();
}
/**
* Create new instance of a resource method handler model.
*
* @param parameters handler parameters associated directly with the resource method handler
* (e.g. class-level property setters and fields). May be {@code null}.
* @since 2.20
*/
protected MethodHandler(final Collection<Parameter> parameters) {
if (parameters != null) {
this.handlerParameters = Collections.unmodifiableCollection(new ArrayList<>(parameters));
} else {
this.handlerParameters = Collections.emptyList();
}
}
/**
* Create a class-based method handler from a class.
*
* @param handlerClass method handler class.
* @return new class-based method handler.
*/
public static MethodHandler create(final Class<?> handlerClass) {
return new ClassBasedMethodHandler(handlerClass, null);
}
/**
* Create a class-based method handler from a class.
*
* @param handlerClass method handler class.
* @param keepConstructorParamsEncoded if set to {@code true}, any injected constructor
* parameters must be kept encoded and must not be automatically decoded.
* @return new class-based method handler.
*/
public static MethodHandler create(final Class<?> handlerClass, final boolean keepConstructorParamsEncoded) {
return new ClassBasedMethodHandler(handlerClass, keepConstructorParamsEncoded, null);
}
/**
* Create a instance-based (singleton) method handler from a class.
*
* @param handlerInstance method handler instance (singleton).
* @return new instance-based method handler.
*/
public static MethodHandler create(final Object handlerInstance) {
return new InstanceBasedMethodHandler(handlerInstance, null);
}
/**
* Create a instance-based (singleton) method handler from a class.
*
* @param handlerInstance method handler instance (singleton).
* @param handlerClass declared handler class.
* @return new instance-based method handler.
*/
public static MethodHandler create(final Object handlerInstance, Class<?> handlerClass) {
return new InstanceBasedMethodHandler(handlerInstance, handlerClass, null);
}
/**
* Create a class-based method handler from a class.
*
* @param handlerClass method handler class.
* @param handlerParameters method handler parameters (e.g. class-level property setters and fields).
* @return new class-based method handler.
*/
public static MethodHandler create(final Class<?> handlerClass, final Collection<Parameter> handlerParameters) {
return new ClassBasedMethodHandler(handlerClass, handlerParameters);
}
/**
* Create a class-based method handler from a class.
*
* @param handlerClass method handler class.
* @param keepConstructorParamsEncoded if set to {@code true}, any injected constructor
* parameters must be kept encoded and must not be automatically decoded.
* @param handlerParameters method handler parameters (e.g. class-level property setters and fields).
* @return new class-based method handler.
* @since 2.20
*/
public static MethodHandler create(final Class<?> handlerClass,
final boolean keepConstructorParamsEncoded,
final Collection<Parameter> handlerParameters) {
return new ClassBasedMethodHandler(handlerClass, keepConstructorParamsEncoded, handlerParameters);
}
/**
* Create a instance-based (singleton) method handler from a class.
*
* @param handlerInstance method handler instance (singleton).
* @param handlerParameters method handler parameters (e.g. class-level property setters and fields).
* @return new instance-based method handler.
* @since 2.20
*/
public static MethodHandler create(final Object handlerInstance, final Collection<Parameter> handlerParameters) {
return new InstanceBasedMethodHandler(handlerInstance, handlerParameters);
}
/**
* Create a instance-based (singleton) method handler from a class.
*
* @param handlerInstance method handler instance (singleton).
* @param handlerClass declared handler class.
* @param handlerParameters method handler parameters (e.g. class-level property setters and fields).
* @return new instance-based method handler.
* @since 2.20
*/
public static MethodHandler create(final Object handlerInstance,
Class<?> handlerClass,
final Collection<Parameter> handlerParameters) {
return new InstanceBasedMethodHandler(handlerInstance, handlerClass, handlerParameters);
}
/**
* Get the resource method handler class.
*
* @return resource method handler class.
*/
public abstract Class<?> getHandlerClass();
/**
* Get the resource method handler constructors.
* <p/>
* The returned is empty by default. Concrete implementations may override
* the method to return the actual list of constructors that will be used
* for the handler initialization.
*
* @return resource method handler constructors.
*/
public List<HandlerConstructor> getConstructors() {
return Collections.emptyList();
}
/**
* Get the injected resource method handler instance.
*
* @param injectionManager injection manager that can be used to inject get the instance.
* @return injected resource method handler instance.
*/
public abstract Object getInstance(final InjectionManager injectionManager);
/**
* Return whether the method handler {@link InjectionManager creates instances}
* based on {@link Class classes}.
*
* @return True is instances returned by this method handler are created from {@link Class classes} given to
* {@code InjectionManager}, false otherwise (for example when method handler was initialized from instance)
*/
public abstract boolean isClassBased();
/**
* Get the parameters associated directly with the resource method handler, if any
* (e.g. class-level property setters and fields).
* <p>
* Note that this method does not return any parameters associated with
* {@link #getConstructors() method handler constructors}.
* </p>
*
* @return parameters associated with the resource method handler. May return an empty collection
* but does not return {@code null}.
* @since 2.20
*/
public Collection<Parameter> getParameters() {
return handlerParameters;
}
@Override
public List<? extends ResourceModelComponent> getComponents() {
return null;
}
@Override
public void accept(final ResourceModelVisitor visitor) {
visitor.visitMethodHandler(this);
}
private static class ClassBasedMethodHandler extends MethodHandler {
private final Class<?> handlerClass;
private final List<HandlerConstructor> handlerConstructors;
public ClassBasedMethodHandler(final Class<?> handlerClass, final Collection<Parameter> handlerParameters) {
this(handlerClass, handlerClass.isAnnotationPresent(Encoded.class), handlerParameters);
}
public ClassBasedMethodHandler(final Class<?> handlerClass,
final boolean disableParamDecoding,
final Collection<Parameter> handlerParameters) {
super(handlerParameters);
this.handlerClass = handlerClass;
List<HandlerConstructor> constructors = new LinkedList<HandlerConstructor>();
for (Constructor<?> constructor : handlerClass.getConstructors()) {
constructors.add(new HandlerConstructor(
constructor, Parameter.create(handlerClass, handlerClass, constructor, disableParamDecoding)));
}
this.handlerConstructors = Collections.unmodifiableList(constructors);
}
@Override
public Class<?> getHandlerClass() {
return handlerClass;
}
@Override
public List<HandlerConstructor> getConstructors() {
return handlerConstructors;
}
@Override
public Object getInstance(final InjectionManager injectionManager) {
return Injections.getOrCreate(injectionManager, handlerClass);
}
@Override
public boolean isClassBased() {
return true;
}
@Override
protected Object getHandlerInstance() {
return null;
}
@Override
public List<? extends ResourceModelComponent> getComponents() {
return handlerConstructors;
}
@Override
public String toString() {
return "ClassBasedMethodHandler{"
+ "handlerClass=" + handlerClass
+ ", handlerConstructors=" + handlerConstructors + '}';
}
}
private static class InstanceBasedMethodHandler extends MethodHandler {
private final Object handler;
private final Class<?> handlerClass;
public InstanceBasedMethodHandler(final Object handler, final Collection<Parameter> handlerParameters) {
super(handlerParameters);
this.handler = handler;
this.handlerClass = handler.getClass();
}
public InstanceBasedMethodHandler(final Object handler,
final Class<?> handlerClass,
final Collection<Parameter> handlerParameters) {
super(handlerParameters);
this.handler = handler;
this.handlerClass = handlerClass;
}
@Override
public Class<?> getHandlerClass() {
return handlerClass;
}
@Override
protected Object getHandlerInstance() {
return handler;
}
@Override
public Object getInstance(final InjectionManager injectionManager) {
return handler;
}
@Override
public boolean isClassBased() {
return false;
}
@Override
public String toString() {
return "InstanceBasedMethodHandler{"
+ "handler=" + handler
+ ", handlerClass=" + handlerClass
+ '}';
}
}
/**
* Get the raw handler instance that is backing this method handler.
*
* @return raw handler instance. May return {@code null} if the handler is
* {@link #isClassBased() class-based}.
*/
protected abstract Object getHandlerInstance();
}