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*** THIS VERSION UPLOADED FOR USE WITH CEDAR-COMMON, TO AVOID DEPENDENCIES ON GOOGLE CODE-BASED MAVEN REPOSITORIES. *** The simplest convenient interface to the Google App Engine datastore

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package com.googlecode.objectify.condition;

import java.lang.reflect.Constructor;
import java.lang.reflect.Field;

import com.googlecode.objectify.impl.TypeUtils;


/**
 * This condition tests against the default value of the field that it
 * is placed upon, whatever that default may be.  If you
 * initialize the field with a value, this condition will use that value
 * as the comparison.  For example, if you have a class like this:
 * 
 *  * public class MyEntity {
 *     @Id Long id;
 *     @NotSaved(IfDefault.class) String foo = "defaultFoo";
 * }
 * 
 * 
 * The {@code foo} field will be left unsaved when it has the value "defaultFoo".
 * 
 * Specifically, this conditional constructs an instance of your entity class
 * using the default (no-arg) constructor and stores the default field value for
 * later comparison.  Note that if you initialize the field in your default constructor,
 * this counts!
 * 
 * @author Jeff Schnitzer 
 */
public class IfDefault extends ValueIf