com.googlecode.objectify.impl.translate.NullSafeTranslator Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of objectify Show documentation

The simplest convenient interface to the Google App Engine datastore

There is a newer version: 6.1.2

package com.googlecode.objectify.impl.translate;

import com.googlecode.objectify.impl.Path;

/**
 * Handles null checking so we don't have to do it everywhere.
 * 
 * @author Jeff Schnitzer 
 */
abstract public class NullSafeTranslator implements Translator
{
	@Override
	final public P load(D node, LoadContext ctx, Path path) throws SkipException {
		if (node == null)
			return null;
		else
			return loadSafe(node, ctx, path);
	}

	@Override
	final public D save(P pojo, boolean index, SaveContext ctx, Path path) throws SkipException {
		if (pojo == null)
			return null;
		else
			return saveSafe(pojo, index, ctx, path);
	}

	/**
	 * Implement this, returning a proper translated value
	 * @param node will never be null
	 */
	abstract protected P loadSafe(D node, LoadContext ctx, Path path) throws SkipException;
	
	/**
	 * Implement this, returning a proper translated value
	 * @param pojo will never be null
	 */
	abstract protected D saveSafe(P pojo, boolean index, SaveContext ctx, Path path) throws SkipException;
}