org.eclipse.persistence.sdo.SDOExternalizableDelegator Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation
EclipseLink build based upon Git transaction 346465e
There is a newer version: 5.0.0-B05
/*******************************************************************************
 * Copyright (c) 1998, 2015 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 v1.0 and Eclipse Distribution License v. 1.0 
 * which accompanies this distribution. 
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at 
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
 ******************************************************************************/ 
package org.eclipse.persistence.sdo;

import java.io.IOException;
import java.io.ObjectInput;
import java.lang.reflect.Field;

import org.eclipse.persistence.exceptions.SDOException;
import org.eclipse.persistence.internal.security.PrivilegedGetField;
import org.eclipse.persistence.internal.security.PrivilegedGetValueFromField;
import org.eclipse.persistence.internal.security.PrivilegedSetValueInField;
import org.eclipse.persistence.sdo.helper.DataObjectInputStream;
import org.eclipse.persistence.sdo.helper.SDOHelperContext;

import commonj.sdo.helper.HelperContext;
import commonj.sdo.impl.ExternalizableDelegator.Resolvable;
import commonj.sdo.impl.HelperProvider;

public class SDOExternalizableDelegator extends AbstractExternalizableDelegator {

	static final PrivilegedGetField privilegedGetDelegateField = new PrivilegedGetField(AbstractExternalizableDelegator.class, "delegate", true);
	
	public SDOExternalizableDelegator() {
		super();
	}

	public SDOExternalizableDelegator(Object target) {
		super(target);
	}

	public SDOExternalizableDelegator(Object target, HelperContext aContext) {
        // JIRA129: pass the helperContext to the constructor to enable non-static contexts
        // check for context type (if non-static SDOHelperContext then we need to cast to use the non-interface createResolvable function
        // to remove this instanceof check - add createResolvable to the HelperContext interface
        if (aContext instanceof SDOHelperContext) {
			setDelegate(((SDOHelperContext)aContext).createResolvable(target));
        } else {
            // use static helper
			setDelegate(HelperProvider.createResolvable(target));
        }
    }

    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
        // This function is indirectly called by InputStream.readExternalData().
        // We reset the static helperContext set in the default constructor during is.readObject()
        // with the passed in context from the client (either static or dynamic instance)
        if (in instanceof DataObjectInputStream) {
            // only reset non-static implementations
            getDelegate().setHelperContext(((DataObjectInputStream)in).getHelperContext());
        }
		super.readExternal(in);
    }

    private SDOResolvable getDelegate() {
		try {	
			Field delegateField = privilegedGetDelegateField.run();
			PrivilegedGetValueFromField privilegedGetValueFromDelegateField = new PrivilegedGetValueFromField(delegateField, this);
			return (SDOResolvable) privilegedGetValueFromDelegateField.run();
		}catch (NoSuchFieldException nsfException){
			throw SDOException.errorAccessingExternalizableDelegator("delegate", nsfException);
		}catch (IllegalAccessException iaException){
			throw SDOException.errorAccessingExternalizableDelegator("delegate", iaException);
		}
	}

	private void setDelegate(Resolvable resolvable) {
		try {
			Field delegateField = (Field) privilegedGetDelegateField.run();
			PrivilegedSetValueInField privilegedSetValueInDelegateField = new PrivilegedSetValueInField(delegateField, this, resolvable);
			privilegedSetValueInDelegateField.run();
		} catch (NoSuchFieldException nsfException){
			throw SDOException.errorAccessingExternalizableDelegator("delegate", nsfException);
		} catch (IllegalAccessException iaException){
			throw SDOException.errorAccessingExternalizableDelegator("delegate", iaException);
		}		
	}
}