/*
* Copyright (C) 2005 Joe Walnes.
* Copyright (C) 2006, 2007, 2008, 2010, 2011 XStream Committers.
* All rights reserved.
*
* The software in this package is published under the terms of the BSD
* style license a copy of which has been included with this distribution in
* the LICENSE.txt file.
*
* Created on 12. April 2005 by Joe Walnes
*/
package com.thoughtworks.xstream.converters.javabean;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import com.thoughtworks.xstream.converters.reflection.ObjectAccessException;
public class BeanProvider implements JavaBeanProvider {
protected static final Object[] NO_PARAMS = new Object[0];
protected PropertyDictionary propertyDictionary;
/**
* Construct a BeanProvider that will process the bean properties in their natural order.
*/
public BeanProvider() {
this(new PropertyDictionary(new NativePropertySorter()));
}
/**
* Construct a BeanProvider with a comparator to sort the bean properties by name in the
* dictionary.
*
* @param propertyNameComparator the comparator
*/
public BeanProvider(final Comparator propertyNameComparator) {
this(new PropertyDictionary(new ComparingPropertySorter(propertyNameComparator)));
}
/**
* Construct a BeanProvider with a provided property dictionary.
*
* @param propertyDictionary the property dictionary to use
* @since 1.4
*/
public BeanProvider(final PropertyDictionary propertyDictionary) {
this.propertyDictionary = propertyDictionary;
}
public Object newInstance(Class type) {
try {
return getDefaultConstrutor(type).newInstance(NO_PARAMS);
} catch (InstantiationException e) {
throw new ObjectAccessException("Cannot construct " + type.getName(), e);
} catch (IllegalAccessException e) {
throw new ObjectAccessException("Cannot construct " + type.getName(), e);
} catch (InvocationTargetException e) {
if (e.getTargetException() instanceof RuntimeException) {
throw (RuntimeException)e.getTargetException();
} else if (e.getTargetException() instanceof Error) {
throw (Error)e.getTargetException();
} else {
throw new ObjectAccessException("Constructor for "
+ type.getName()
+ " threw an exception", e);
}
}
}
public void visitSerializableProperties(Object object, JavaBeanProvider.Visitor visitor) {
PropertyDescriptor[] propertyDescriptors = getSerializableProperties(object);
for (int i = 0; i < propertyDescriptors.length; i++ ) {
PropertyDescriptor property = propertyDescriptors[i];
try {
Method readMethod = property.getReadMethod();
String name = property.getName();
Class definedIn = readMethod.getDeclaringClass();
if (visitor.shouldVisit(name, definedIn)) {
Object value = readMethod.invoke(object, new Object[0]);
visitor.visit(name, property.getPropertyType(), definedIn, value);
}
} catch (IllegalArgumentException e) {
throw new ObjectAccessException("Could not get property "
+ object.getClass()
+ "."
+ property.getName(), e);
} catch (IllegalAccessException e) {
throw new ObjectAccessException("Could not get property "
+ object.getClass()
+ "."
+ property.getName(), e);
} catch (InvocationTargetException e) {
throw new ObjectAccessException("Could not get property "
+ object.getClass()
+ "."
+ property.getName(), e);
}
}
}
public void writeProperty(Object object, String propertyName, Object value) {
PropertyDescriptor property = getProperty(propertyName, object.getClass());
try {
property.getWriteMethod().invoke(object, new Object[]{value});
} catch (IllegalArgumentException e) {
throw new ObjectAccessException("Could not set property "
+ object.getClass()
+ "."
+ property.getName(), e);
} catch (IllegalAccessException e) {
throw new ObjectAccessException("Could not set property "
+ object.getClass()
+ "."
+ property.getName(), e);
} catch (InvocationTargetException e) {
throw new ObjectAccessException("Could not set property "
+ object.getClass()
+ "."
+ property.getName(), e);
}
}
public Class getPropertyType(Object object, String name) {
return getProperty(name, object.getClass()).getPropertyType();
}
public boolean propertyDefinedInClass(String name, Class type) {
return getProperty(name, type) != null;
}
/**
* Returns true if the Bean provider can instantiate the specified class
*/
public boolean canInstantiate(Class type) {
return getDefaultConstrutor(type) != null;
}
/**
* Returns the default constructor, or null if none is found
*
* @param type
*/
protected Constructor getDefaultConstrutor(Class type) {
Constructor[] constructors = type.getConstructors();
for (int i = 0; i < constructors.length; i++ ) {
Constructor c = constructors[i];
if (c.getParameterTypes().length == 0 && Modifier.isPublic(c.getModifiers()))
return c;
}
return null;
}
protected PropertyDescriptor[] getSerializableProperties(Object object) {
List result = new ArrayList();
for (final Iterator iter = propertyDictionary.propertiesFor(object.getClass()); iter.hasNext();) {
final PropertyDescriptor descriptor = (PropertyDescriptor)iter.next();
if (canStreamProperty(descriptor)) {
result.add(descriptor);
}
}
return (PropertyDescriptor[])result.toArray(new PropertyDescriptor[result.size()]);
}
protected boolean canStreamProperty(PropertyDescriptor descriptor) {
return descriptor.getReadMethod() != null && descriptor.getWriteMethod() != null;
}
public boolean propertyWriteable(String name, Class type) {
PropertyDescriptor property = getProperty(name, type);
return property.getWriteMethod() != null;
}
protected PropertyDescriptor getProperty(String name, Class type) {
return (PropertyDescriptor)propertyDictionary.propertyDescriptor(type, name);
}
/**
* @deprecated As of 1.4 use {@link JavaBeanProvider.Visitor}
*/
public interface Visitor extends JavaBeanProvider.Visitor {
}
}