/*
* Copyright 2002-2008 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.validation;
import org.springframework.beans.ConfigurablePropertyAccessor;
import org.springframework.beans.PropertyAccessorFactory;
import org.springframework.util.Assert;
/**
* Special implementation of the Errors and BindingResult interfaces,
* supporting registration and evaluation of binding errors on value objects.
* Performs direct field access instead of going through JavaBean getters.
*
* <p>This implementation just supports fields in the actual target object.
* It is not able to traverse nested fields.
*
* @author Juergen Hoeller
* @since 2.0
* @see DataBinder#getBindingResult()
* @see DataBinder#initDirectFieldAccess()
* @see BeanPropertyBindingResult
*/
public class DirectFieldBindingResult extends AbstractPropertyBindingResult {
private final Object target;
private transient ConfigurablePropertyAccessor directFieldAccessor;
/**
* Create a new DirectFieldBindingResult instance.
* @param target the target object to bind onto
* @param objectName the name of the target object
*/
public DirectFieldBindingResult(Object target, String objectName) {
super(objectName);
this.target = target;
}
@Override
public final Object getTarget() {
return this.target;
}
/**
* Returns the DirectFieldAccessor that this instance uses.
* Creates a new one if none existed before.
* @see #createDirectFieldAccessor()
*/
@Override
public final ConfigurablePropertyAccessor getPropertyAccessor() {
if (this.directFieldAccessor == null) {
this.directFieldAccessor = createDirectFieldAccessor();
this.directFieldAccessor.setExtractOldValueForEditor(true);
}
return this.directFieldAccessor;
}
/**
* Create a new DirectFieldAccessor for the underlying target object.
* @see #getTarget()
*/
protected ConfigurablePropertyAccessor createDirectFieldAccessor() {
Assert.state(this.target != null, "Cannot access fields on null target instance '" + getObjectName() + "'!");
return PropertyAccessorFactory.forDirectFieldAccess(this.target);
}
}
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