/*
* Copyright 2014 Daniel Bechler
*
* 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 de.danielbechler.diff.introspection;
import de.danielbechler.diff.access.PropertyAwareAccessor;
import de.danielbechler.diff.instantiation.TypeInfo;
import de.danielbechler.util.Assert;
import de.danielbechler.util.Exceptions;
import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
/**
* Resolves the accessors of a given type by using the standard Java {@link Introspector}.
*
* @author Daniel Bechler
*/
public class StandardIntrospector implements de.danielbechler.diff.introspection.Introspector
{
public TypeInfo introspect(final Class<?> type)
{
Assert.notNull(type, "type");
try
{
return internalIntrospect(type);
}
catch (final IntrospectionException e)
{
throw Exceptions.escalate(e);
}
}
private TypeInfo internalIntrospect(final Class<?> type) throws IntrospectionException
{
final TypeInfo typeInfo = new TypeInfo(type);
final PropertyDescriptor[] descriptors = getBeanInfo(type).getPropertyDescriptors();
for (final PropertyDescriptor descriptor : descriptors)
{
if (shouldSkip(descriptor))
{
continue;
}
final String propertyName = descriptor.getName();
final Method readMethod = descriptor.getReadMethod();
final Method writeMethod = descriptor.getWriteMethod();
final PropertyAwareAccessor accessor = new PropertyAccessor(propertyName, readMethod, writeMethod);
typeInfo.addPropertyAccessor(accessor);
}
return typeInfo;
}
protected BeanInfo getBeanInfo(final Class<?> type) throws IntrospectionException
{
return Introspector.getBeanInfo(type);
}
private static boolean shouldSkip(final PropertyDescriptor descriptor)
{
if (descriptor.getName().equals("class")) // Java & Groovy
{
return true;
}
if (descriptor.getName().equals("metaClass")) // Groovy
{
return true;
}
if (descriptor.getReadMethod() == null)
{
return true;
}
return false;
}
}