/*
* Copyright 2002-2009 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.beans;
import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.util.HashSet;
import java.util.Set;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.BridgeMethodResolver;
import org.springframework.core.GenericTypeResolver;
import org.springframework.core.MethodParameter;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;
/**
* Extension of the standard JavaBeans PropertyDescriptor class,
* overriding <code>getPropertyType()</code> such that a generically
* declared type will be resolved against the containing bean class.
*
* @author Juergen Hoeller
* @since 2.5.2
*/
class GenericTypeAwarePropertyDescriptor extends PropertyDescriptor {
private final Class beanClass;
private final Method readMethod;
private final Method writeMethod;
private final Class propertyEditorClass;
private volatile Set<Method> ambiguousWriteMethods;
private Class propertyType;
private MethodParameter writeMethodParameter;
public GenericTypeAwarePropertyDescriptor(Class beanClass, String propertyName,
Method readMethod, Method writeMethod, Class propertyEditorClass)
throws IntrospectionException {
super(propertyName, null, null);
this.beanClass = beanClass;
this.propertyEditorClass = propertyEditorClass;
Method readMethodToUse = BridgeMethodResolver.findBridgedMethod(readMethod);
Method writeMethodToUse = BridgeMethodResolver.findBridgedMethod(writeMethod);
if (writeMethodToUse == null && readMethodToUse != null) {
// Fallback: Original JavaBeans introspection might not have found matching setter
// method due to lack of bridge method resolution, in case of the getter using a
// covariant return type whereas the setter is defined for the concrete property type.
writeMethodToUse = ClassUtils.getMethodIfAvailable(this.beanClass,
"set" + StringUtils.capitalize(getName()), readMethodToUse.getReturnType());
}
this.readMethod = readMethodToUse;
this.writeMethod = writeMethodToUse;
if (this.writeMethod != null && this.readMethod == null) {
// Write method not matched against read method: potentially ambiguous through
// several overloaded variants, in which case an arbitrary winner has been chosen
// by the JDK's JavaBeans Introspector...
Set<Method> ambiguousCandidates = new HashSet<Method>();
for (Method method : beanClass.getMethods()) {
if (method.getName().equals(writeMethodToUse.getName()) &&
!method.equals(writeMethodToUse) && !method.isBridge()) {
ambiguousCandidates.add(method);
}
}
if (!ambiguousCandidates.isEmpty()) {
this.ambiguousWriteMethods = ambiguousCandidates;
}
}
}
@Override
public Method getReadMethod() {
return this.readMethod;
}
@Override
public Method getWriteMethod() {
return this.writeMethod;
}
public Method getWriteMethodForActualAccess() {
Set<Method> ambiguousCandidates = this.ambiguousWriteMethods;
if (ambiguousCandidates != null) {
this.ambiguousWriteMethods = null;
LogFactory.getLog(GenericTypeAwarePropertyDescriptor.class).warn("Invalid JavaBean property '" +
getName() + "' being accessed! Ambiguous write methods found next to actually used [" +
this.writeMethod + "]: " + ambiguousCandidates);
}
return this.writeMethod;
}
@Override
public Class getPropertyEditorClass() {
return this.propertyEditorClass;
}
@Override
public synchronized Class getPropertyType() {
if (this.propertyType == null) {
if (this.readMethod != null) {
this.propertyType = GenericTypeResolver.resolveReturnType(this.readMethod, this.beanClass);
}
else {
MethodParameter writeMethodParam = getWriteMethodParameter();
if (writeMethodParam != null) {
this.propertyType = writeMethodParam.getParameterType();
}
else {
this.propertyType = super.getPropertyType();
}
}
}
return this.propertyType;
}
public synchronized MethodParameter getWriteMethodParameter() {
if (this.writeMethod == null) {
return null;
}
if (this.writeMethodParameter == null) {
this.writeMethodParameter = new MethodParameter(this.writeMethod, 0);
GenericTypeResolver.resolveParameterType(this.writeMethodParameter, this.beanClass);
}
return this.writeMethodParameter;
}
}
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