org.hibernate.proxy.ProxyConfiguration Maven / Gradle / Ivy
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or .
*/
package org.hibernate.proxy;
import java.lang.reflect.Method;
import net.bytebuddy.implementation.bind.annotation.AllArguments;
import net.bytebuddy.implementation.bind.annotation.FieldValue;
import net.bytebuddy.implementation.bind.annotation.Origin;
import net.bytebuddy.implementation.bind.annotation.RuntimeType;
import net.bytebuddy.implementation.bind.annotation.StubValue;
import net.bytebuddy.implementation.bind.annotation.This;
/**
* A proxy configuration allows the definition of an interceptor object that decides on the behavior of a proxy.
* This interface is meant for internal use but is in a public package in order to provide code generation.
*
* While this interface depends on Byte Buddy types, this is only true for annotation types which are silently
* suppressed by the runtime if they are not available on a class loader. This allows using this interceptor
* and configuration with for example OSGi without any export of Byte Buddy when using Hibernate.
*/
public interface ProxyConfiguration {
/**
* The canonical field name for an interceptor object stored in a proxied object.
*/
String INTERCEPTOR_FIELD_NAME = "$$_hibernate_interceptor";
/**
* Defines an interceptor object that specifies the behavior of the proxy object.
*
* @param interceptor The interceptor object.
*/
void $$_hibernate_set_interceptor(Interceptor interceptor);
/**
* An interceptor object that is responsible for invoking a proxy's method.
*/
interface Interceptor {
/**
* Intercepts a method call to a proxy.
*
* @param instance The proxied instance.
* @param method The invoked method.
* @param arguments The intercepted method arguments.
*
* @return The method's return value.
*
* @throws Throwable If the intercepted method raises an exception.
*/
@RuntimeType
Object intercept(@This Object instance, @Origin Method method, @AllArguments Object[] arguments) throws Throwable;
}
/**
* An static interceptor that guards against method calls before the interceptor is set.
*/
class InterceptorDispatcher {
/**
* Intercepts a method call to a proxy.
*
* @param instance The proxied instance.
* @param method The invoked method.
* @param arguments The method arguments.
* @param stubValue The intercepted method's default value.
* @param interceptor The proxy object's interceptor instance.
*
* @return The intercepted method's return value.
*
* @throws Throwable If the intercepted method raises an exception.
*/
@RuntimeType
public static Object intercept(
@This final Object instance,
@Origin final Method method,
@AllArguments final Object[] arguments,
@StubValue final Object stubValue,
@FieldValue(INTERCEPTOR_FIELD_NAME) Interceptor interceptor
) throws Throwable {
if ( interceptor == null ) {
if ( method.getName().equals( "getHibernateLazyInitializer" ) ) {
return instance;
}
else {
return stubValue;
}
}
else {
return interceptor.intercept( instance, method, arguments );
}
}
}
}