Invocable.java
/*
* Copyright (c) 2011, 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.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import javax.ws.rs.core.GenericType;
import javax.ws.rs.core.Request;
import org.glassfish.jersey.internal.util.ReflectionHelper;
import org.glassfish.jersey.internal.util.collection.ClassTypePair;
import org.glassfish.jersey.process.Inflector;
/**
* A common interface for invocable resource components. This includes resource
* methods, sub-resource methods and sub-resource locators bound to a concrete
* handler class and a Java method (either directly or indirectly) declared &
* implemented by the handler class.
* <p/>
* Invocable component information is used at runtime by a Java method dispatcher
* when processing requests.
* <p>
* Class defines two kinds of {@link Method java methods}: {@link #getDefinitionMethod() definition method} and
* {@link #getHandlingMethod() handling method}. Definition method is the java {@code Method} that is defined
* by the user to be
* executed. This can be java {@code Method} of the class but also method of the interface. If it is the
* method of the interface (method handler class is the {@code class} but method itself is from
* the {@code interface}) then the definition method is the method from the inherited {@code class}. In other words, the
* handling method is the concrete method but definition method can be its parent abstract definition. However, in most
* cases these methods are the same.
* </p>
*
*
* @author Marek Potociar
* @see ResourceMethod
* @see org.glassfish.jersey.server.spi.internal.ResourceMethodDispatcher
*/
public final class Invocable implements Parameterized, ResourceModelComponent {
/**
* Method instance representing the {@link Inflector#apply(Object)} method.
*/
static final Method APPLY_INFLECTOR_METHOD = initApplyMethod();
private static Method initApplyMethod() {
try {
return Inflector.class.getMethod("apply", Object.class);
} catch (NoSuchMethodException e) {
IncompatibleClassChangeError error = new IncompatibleClassChangeError("Inflector.apply(Object) method not found");
error.initCause(e);
throw error;
}
}
/**
* Create a new resource method invocable model backed by an inflector instance.
*
* @param inflector inflector processing the request method.
*
* @return Invocable.
*/
public static <T> Invocable create(Inflector<Request, T> inflector) {
return create(MethodHandler.create(inflector), APPLY_INFLECTOR_METHOD, false);
}
/**
* Create a new resource method invocable model backed by an inflector class.
*
* @param inflectorClass inflector syb-type processing the request method.
* @return Invocable.
*/
public static Invocable create(Class<? extends Inflector> inflectorClass) {
return create(MethodHandler.create(inflectorClass), APPLY_INFLECTOR_METHOD, false);
}
/**
* Create a new resource method invocable model. Parameter values will be
* automatically decoded.
*
* @param handler resource method handler.
* @param handlingMethod handling Java method.
* @return Invocable.
*/
public static Invocable create(MethodHandler handler, Method handlingMethod) {
return create(handler, handlingMethod, false);
}
/**
* Create a new resource method invocable model.
*
* @param handler resource method handler.
* @param definitionMethod method that is defined to be executed on the {@code handler}.
* @param encodedParameters {@code true} if the automatic parameter decoding
* should be disabled, false otherwise.
* @return Invocable
*/
public static Invocable create(MethodHandler handler, Method definitionMethod, boolean encodedParameters) {
return create(handler, definitionMethod, null, encodedParameters);
}
/**
* Create a new resource method invocable model.
*
* @param handler resource method handler.
* @param definitionMethod method that is defined to be executed on the {@code handler}.
* @param handlingMethod specific and concrete method to be actually executed as a resource method. If {@code null}
* then the {@code definitionMethod} will be used.
* @param encodedParameters {@code true} if the automatic parameter decoding
* should be disabled, false otherwise.
* @return Invocable.
*/
public static Invocable create(MethodHandler handler, Method definitionMethod, Method handlingMethod,
boolean encodedParameters) {
return new Invocable(handler, definitionMethod, handlingMethod, encodedParameters, null);
}
/**
* Create a new resource method invocable model.
*
* @param handler resource method handler.
* @param definitionMethod method that is defined to be executed on the {@code handler}.
* @param handlingMethod specific and concrete method to be actually executed as a resource method. If {@code null}
* then the {@code definitionMethod} will be used.
* @param encodedParameters {@code true} if the automatic parameter decoding
* should be disabled, false otherwise.
* @param routingResponseType response type that will be used during the routing for purpose
* of selection of the resource method to be executed. If this parameter is
* non-{@code null} then it will override the return type of the
* {@link #getHandlingMethod() the Java handling method}) for purposes of
* resource method selection. This might be useful in cases when resource
* method returns a type {@code A} but thanks to registered providers
* (eg. {@link javax.ws.rs.ext.WriterInterceptor}) it will be always converted
* to type {@code B}. Then the method selecting algorithm would check presence of
* {@link javax.ws.rs.ext.MessageBodyWriter} for type {@code A} (which will
* never be actually needed) and might result in choosing undesired method.
* If the parameter is {@code null} then the default response type will be used.
*
* @return Invocable.
*/
public static Invocable create(MethodHandler handler, Method definitionMethod, Method handlingMethod,
boolean encodedParameters, Type routingResponseType) {
return new Invocable(handler, definitionMethod, handlingMethod, encodedParameters, routingResponseType);
}
private final MethodHandler handler;
private final Method definitionMethod;
private final Method handlingMethod;
private final List<Parameter> parameters;
private final Class<?> rawResponseType;
private final Type responseType;
private final Type routingResponseType;
private final Class<?> rawRoutingResponseType;
private Invocable(MethodHandler handler, Method definitionMethod, Method handlingMethod, boolean encodedParameters,
Type routingResponseType) {
this.handler = handler;
this.definitionMethod = definitionMethod;
this.handlingMethod = handlingMethod == null ? ReflectionHelper
.findOverridingMethodOnClass(handler.getHandlerClass(), definitionMethod) : handlingMethod;
final Class<?> handlerClass = handler.getHandlerClass();
final Class<?> definitionClass = definitionMethod.getDeclaringClass();
final ClassTypePair handlingCtPair = ReflectionHelper.resolveGenericType(
handlerClass,
this.handlingMethod.getDeclaringClass(),
this.handlingMethod.getReturnType(),
this.handlingMethod.getGenericReturnType());
// here we need to find types also for definition method. Definition method is in most
// cases used for parent methods (for example for interface method of resource class). But here we
// consider also situation when resource is a proxy (for example proxy of EJB) and definition
// method is the original method and handling method is method on proxy. So, we try to find generic
// type in the original class using definition method.
final ClassTypePair definitionCtPair = ReflectionHelper.resolveGenericType(
definitionClass,
this.definitionMethod.getDeclaringClass(),
this.definitionMethod.getReturnType(),
this.definitionMethod.getGenericReturnType());
this.rawResponseType = handlingCtPair.rawClass();
final boolean handlerReturnTypeIsParameterized = handlingCtPair.type() instanceof ParameterizedType;
final boolean definitionReturnTypeIsParameterized = definitionCtPair.type() instanceof ParameterizedType;
this.responseType =
(handlingCtPair.rawClass() == definitionCtPair.rawClass()
&& definitionReturnTypeIsParameterized && !handlerReturnTypeIsParameterized)
? definitionCtPair.type() : handlingCtPair.type();
if (routingResponseType == null) {
this.routingResponseType = responseType;
this.rawRoutingResponseType = rawResponseType;
} else {
GenericType routingResponseGenericType = new GenericType(routingResponseType);
this.routingResponseType = routingResponseGenericType.getType();
this.rawRoutingResponseType = routingResponseGenericType.getRawType();
}
this.parameters = Collections.unmodifiableList(Parameter.create(
handlerClass, definitionMethod.getDeclaringClass(), definitionMethod, encodedParameters));
}
/**
* Get the model of the resource method handler that will be used to invoke
* the {@link #getHandlingMethod() handling resource method} on.
*
* @return resource method handler model.
*/
public MethodHandler getHandler() {
return handler;
}
/**
* Getter for the Java method
*
* @return corresponding Java method
*/
public Method getHandlingMethod() {
return handlingMethod;
}
/**
* Getter for the Java method that should be executed.
*
* @return corresponding Java method.
*/
public Method getDefinitionMethod() {
return definitionMethod;
}
/**
* Get the resource method generic response type information.
* <p>
* The returned value provides the Type information that contains additional
* generic declaration information for generic Java class types.
* </p>
*
* @return resource method generic response type information.
*/
public Type getResponseType() {
return responseType;
}
/**
* Get the resource method raw response type.
* <p>
* The returned value provides information about the raw Java class.
* </p>
*
* @return resource method raw response type information.
*/
public Class<?> getRawResponseType() {
return rawResponseType;
}
/**
* Check if the invocable represents an {@link Inflector#apply(Object) inflector
* processing method}.
*
* @return {@code true}, if this invocable represents an inflector invocation,
* {@code false} otherwise.
*/
public boolean isInflector() {
// Method.equals(...) does not perform the identity check (in Java SE 6)
return APPLY_INFLECTOR_METHOD == definitionMethod || APPLY_INFLECTOR_METHOD.equals(definitionMethod);
}
@Override
public boolean requiresEntity() {
for (Parameter p : getParameters()) {
if (Parameter.Source.ENTITY == p.getSource()) {
return true;
}
}
return false;
}
@Override
public List<Parameter> getParameters() {
return parameters;
}
@Override
public void accept(ResourceModelVisitor visitor) {
visitor.visitInvocable(this);
}
@Override
public List<? extends ResourceModelComponent> getComponents() {
return Arrays.asList(handler);
}
@Override
public String toString() {
return "Invocable{"
+ "handler=" + handler
+ ", definitionMethod=" + definitionMethod
+ ", parameters=" + parameters
+ ", responseType=" + responseType + '}';
}
/**
* Get the response type of the {@link #handlingMethod} that will be used during
* the routing for the purpose
* of selection of the resource method. Returned value
* is in most cases equal to the {@link #getResponseType() response type}.
* If returned value is different then it overrides the response type for
* purposes of resource method selection and will be used to look for available
* {@link javax.ws.rs.ext.MessageBodyWriter message body writers}.
*
* @return Response type used for the routing.
*/
public Type getRoutingResponseType() {
return routingResponseType;
}
/**
* Get the response {@link Class} of the {@link #handlingMethod} that will be used during
* the routing for the purpose
* of selection of the resource method. Returned value
* is in most cases equal to the {@link #getResponseType() response type}.
* If returned value is different then it overrides the response type for
* purposes of resource method selection and will be used to look for available
* {@link javax.ws.rs.ext.MessageBodyWriter message body writers}.
*
* @return Response type used for the routing.
*/
public Class<?> getRawRoutingResponseType() {
return rawRoutingResponseType;
}
}