org.hibernate.proxy.pojo.BasicLazyInitializer.java Source code

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Here is the source code for org.hibernate.proxy.pojo.BasicLazyInitializer.java

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/*
 * 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 <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
package org.hibernate.proxy.pojo;

import java.io.Serializable;
import java.lang.reflect.Method;

import org.hibernate.engine.spi.SharedSessionContractImplementor;
import org.hibernate.internal.util.MarkerObject;
import org.hibernate.proxy.AbstractLazyInitializer;
import org.hibernate.type.CompositeType;

/**
 * Lazy initializer for POJOs
 *
 * @author Gavin King
 */
public abstract class BasicLazyInitializer extends AbstractLazyInitializer {

    protected static final Object INVOKE_IMPLEMENTATION = new MarkerObject("INVOKE_IMPLEMENTATION");

    protected final Class persistentClass;
    protected final Method getIdentifierMethod;
    protected final Method setIdentifierMethod;
    protected final boolean overridesEquals;
    protected final CompositeType componentIdType;

    private Object replacement;

    protected BasicLazyInitializer(String entityName, Class persistentClass, Serializable id,
            Method getIdentifierMethod, Method setIdentifierMethod, CompositeType componentIdType,
            SharedSessionContractImplementor session, boolean overridesEquals) {
        super(entityName, id, session);
        this.persistentClass = persistentClass;
        this.getIdentifierMethod = getIdentifierMethod;
        this.setIdentifierMethod = setIdentifierMethod;
        this.componentIdType = componentIdType;
        this.overridesEquals = overridesEquals;
    }

    protected abstract Object serializableProxy();

    protected final Object invoke(Method method, Object[] args, Object proxy) throws Throwable {
        String methodName = method.getName();
        int params = args.length;

        if (params == 0) {
            if ("writeReplace".equals(methodName)) {
                return getReplacement();
            } else if (!overridesEquals && "hashCode".equals(methodName)) {
                return System.identityHashCode(proxy);
            } else if (isUninitialized() && method.equals(getIdentifierMethod)) {
                return getIdentifier();
            } else if ("getHibernateLazyInitializer".equals(methodName)) {
                return this;
            }
        } else if (params == 1) {
            if (!overridesEquals && "equals".equals(methodName)) {
                return args[0] == proxy;
            } else if (method.equals(setIdentifierMethod)) {
                initialize();
                setIdentifier((Serializable) args[0]);
                return INVOKE_IMPLEMENTATION;
            }
        }

        //if it is a property of an embedded component, invoke on the "identifier"
        if (componentIdType != null && componentIdType.isMethodOf(method)) {
            return method.invoke(getIdentifier(), args);
        }

        // otherwise:
        return INVOKE_IMPLEMENTATION;

    }

    private Object getReplacement() {
        /*
         * If the target has already been loaded somewhere, just not set on the proxy,
         * then use it to initialize the proxy so that we will serialize that instead of the proxy.
         */
        initializeWithoutLoadIfPossible();

        if (isUninitialized()) {
            if (replacement == null) {
                prepareForPossibleLoadingOutsideTransaction();
                replacement = serializableProxy();
            }
            return replacement;
        } else {
            return getTarget();
        }

    }

    public final Class getPersistentClass() {
        return persistentClass;
    }

}