/*
* Copyright 2002-2018 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;
/**
* 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>Since Spring 4.1 this implementation is able to traverse nested fields.
*
* @author Juergen Hoeller
* @since 2.0
* @see DataBinder#getBindingResult()
* @see DataBinder#initDirectFieldAccess()
* @see BeanPropertyBindingResult
*/
@
SuppressWarnings("serial")
public class
DirectFieldBindingResult extends
AbstractPropertyBindingResult {
private final
Object target;
private final boolean
autoGrowNestedPaths;
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) {
this(
target,
objectName, true);
}
/**
* Create a new DirectFieldBindingResult instance.
* @param target the target object to bind onto
* @param objectName the name of the target object
* @param autoGrowNestedPaths whether to "auto-grow" a nested path that contains a null value
*/
public
DirectFieldBindingResult(
Object target,
String objectName, boolean
autoGrowNestedPaths) {
super(
objectName);
this.
target =
target;
this.
autoGrowNestedPaths =
autoGrowNestedPaths;
}
@
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);
this.
directFieldAccessor.
setAutoGrowNestedPaths(this.
autoGrowNestedPaths);
}
return this.
directFieldAccessor;
}
/**
* Create a new DirectFieldAccessor for the underlying target object.
* @see #getTarget()
*/
protected
ConfigurablePropertyAccessor createDirectFieldAccessor() {
if (this.
target == null) {
throw new
IllegalStateException("Cannot access fields on null target instance '" +
getObjectName() + "'");
}
return
PropertyAccessorFactory.
forDirectFieldAccess(this.
target);
}
}