/*
* Copyright 2001-2004 The Apache Software Foundation.
*
* 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.oddjob.framework;
import org.apache.commons.beanutils.ConversionException;
import org.apache.commons.beanutils.DynaBean;
import org.apache.commons.beanutils.DynaProperty;
import org.apache.commons.beanutils.PropertyUtils;
import org.oddjob.arooa.reflect.ArooaClass;
import org.oddjob.arooa.reflect.ArooaClassFactory;
import org.oddjob.arooa.reflect.ArooaClasses;
/**
* <p>Implementation of <code>DynaBean</code> that wraps a standard JavaBean
* instance, so that DynaBean APIs can be used to access its properties.</p>
*
* <p>
* The most common use cases for this class involve wrapping an existing java bean.
* (This makes it different from the typical use cases for other <code>DynaBean</code>'s.)
* For example:
* </p>
* <code><pre>
* Object aJavaBean = ...;
* ...
* DynaBean db = new WrapDynaBean(aJavaBean);
* ...
* </pre></code>
*
* <p><strong>IMPLEMENTATION NOTE</strong> - This implementation does not
* support the <code>contains()</code> and <code>remove()</code> methods.</p>
*
* <p>
* Based on the BeanUtils version but provide a Serializable DynaClass.
*
* @author Rob Gorodon, based on the original from BeanUtils.
*/
public class WrapDynaBean implements DynaBean {
static {
ArooaClasses.register(WrapDynaBean.class,
new ArooaClassFactory<WrapDynaBean>() {
@Override
public ArooaClass classFor(WrapDynaBean instance) {
return new WrapDynaArooaClass(instance.getDynaClass(),
instance.getClass());
}
});
}
// ---------------------------------------------------------- Constructors
/**
* Construct a new <code>DynaBean</code> associated with the specified
* JavaBean instance.
*
* @param instance JavaBean instance to be wrapped
*/
public WrapDynaBean(Object instance) {
super();
this.instance = instance;
this.dynaClass = WrapDynaClass.createDynaClass(instance.getClass());
}
// ---------------------------------------------------- Instance Variables
/**
* The <code>DynaClass</code> "base class" that this DynaBean
* is associated with.
*/
protected WrapDynaClass dynaClass = null;
/**
* The JavaBean instance wrapped by this WrapDynaBean.
*/
protected Object instance = null;
// ------------------------------------------------------ DynaBean Methods
/**
* Does the specified mapped property contain a value for the specified
* key value?
*
* @param name Name of the property to check
* @param key Name of the key to check
*
* @exception IllegalArgumentException if there is no property
* of the specified name
*/
public boolean contains(String name, String key) {
throw new UnsupportedOperationException
("WrapDynaBean does not support contains()");
}
/**
* Return the value of a simple property with the specified name.
*
* @param name Name of the property whose value is to be retrieved
*
* @exception IllegalArgumentException if there is no property
* of the specified name
*/
public Object get(String name) {
if (!dynaClass.isReadable(name)) {
return null;
}
Object value = null;
try {
value = PropertyUtils.getSimpleProperty(instance, name);
} catch (Throwable t) {
throw new RuntimeException("Failed getting property " + name, t);
}
return (value);
}
/**
* Return the value of an indexed property with the specified name.
*
* @param name Name of the property whose value is to be retrieved
* @param index Index of the value to be retrieved
*
* @exception IllegalArgumentException if there is no property
* of the specified name
* @exception IllegalArgumentException if the specified property
* exists, but is not indexed
* @exception IndexOutOfBoundsException if the specified index
* is outside the range of the underlying property
* @exception NullPointerException if no array or List has been
* initialized for this property
*/
public Object get(String name, int index) {
if (!dynaClass.isReadable(name)) {
return null;
}
Object value = null;
try {
value = PropertyUtils.getIndexedProperty(instance, name, index);
} catch (IndexOutOfBoundsException e) {
throw e;
} catch (Throwable t) {
throw new IllegalArgumentException
("Property '" + name + "' has no indexed read method");
}
return (value);
}
/**
* Return the value of a mapped property with the specified name,
* or <code>null</code> if there is no value for the specified key.
*
* @param name Name of the property whose value is to be retrieved
* @param key Key of the value to be retrieved
*
* @exception IllegalArgumentException if there is no property
* of the specified name
* @exception IllegalArgumentException if the specified property
* exists, but is not mapped
*/
public Object get(String name, String key) {
if (!dynaClass.isReadable(name)) {
return null;
}
Object value = null;
try {
value = PropertyUtils.getMappedProperty(instance, name, key);
} catch (Throwable t) {
throw new IllegalArgumentException
("Property '" + name + "' has no mapped read method");
}
return (value);
}
/**
* Return the <code>DynaClass</code> instance that describes the set of
* properties available for this DynaBean.
*/
public WrapDynaClass getDynaClass() {
return (this.dynaClass);
}
/**
* Remove any existing value for the specified key on the
* specified mapped property.
*
* @param name Name of the property for which a value is to
* be removed
* @param key Key of the value to be removed
*
* @exception IllegalArgumentException if there is no property
* of the specified name
*/
public void remove(String name, String key) {
throw new UnsupportedOperationException
("WrapDynaBean does not support remove()");
}
/**
* Set the value of a simple property with the specified name.
*
* @param name Name of the property whose value is to be set
* @param value Value to which this property is to be set
*
* @exception ConversionException if the specified value cannot be
* converted to the type required for this property
* @exception IllegalArgumentException if there is no property
* of the specified name
* @exception NullPointerException if an attempt is made to set a
* primitive property to null
*/
public void set(String name, Object value) {
try {
PropertyUtils.setSimpleProperty(instance, name, value);
} catch (Throwable t) {
throw new IllegalArgumentException
("Property '" + name + "' has no write method");
}
}
/**
* Set the value of an indexed property with the specified name.
*
* @param name Name of the property whose value is to be set
* @param index Index of the property to be set
* @param value Value to which this property is to be set
*
* @exception ConversionException if the specified value cannot be
* converted to the type required for this property
* @exception IllegalArgumentException if there is no property
* of the specified name
* @exception IllegalArgumentException if the specified property
* exists, but is not indexed
* @exception IndexOutOfBoundsException if the specified index
* is outside the range of the underlying property
*/
public void set(String name, int index, Object value) {
try {
PropertyUtils.setIndexedProperty(instance, name, index, value);
} catch (IndexOutOfBoundsException e) {
throw e;
} catch (Throwable t) {
throw new IllegalArgumentException
("Property '" + name + "' has no indexed write method");
}
}
/**
* Set the value of a mapped property with the specified name.
*
* @param name Name of the property whose value is to be set
* @param key Key of the property to be set
* @param value Value to which this property is to be set
*
* @exception ConversionException if the specified value cannot be
* converted to the type required for this property
* @exception IllegalArgumentException if there is no property
* of the specified name
* @exception IllegalArgumentException if the specified property
* exists, but is not mapped
*/
public void set(String name, String key, Object value) {
try {
PropertyUtils.setMappedProperty(instance, name, key, value);
} catch (Throwable t) {
throw new IllegalArgumentException
("Property '" + name + "' has no mapped write method");
}
}
/**
* Gets the bean instance wrapped by this DynaBean.
* For most common use cases,
* this object should already be known
* and this method safely be ignored.
* But some creators of frameworks using <code>DynaBean</code>'s may
* find this useful.
*
* @return the java bean Object wrapped by this <code>DynaBean</code>
*/
public Object getInstance() {
return instance;
}
// ------------------------------------------------------ Protected Methods
/**
* Return the property descriptor for the specified property name.
*
* @param name Name of the property for which to retrieve the descriptor
*
* @exception IllegalArgumentException if this is not a valid property
* name for our DynaClass
*/
protected DynaProperty getDynaProperty(String name) {
DynaProperty descriptor = getDynaClass().getDynaProperty(name);
if (descriptor == null) {
throw new IllegalArgumentException
("Invalid property name '" + name + "'");
}
return (descriptor);
}
}