org.apache.commons.beanutils.BasicDynaClass Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.commons.beanutils;
import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.HashMap;
/**
* Minimal implementation of the DynaClass interface. Can be
* used as a convenience base class for more sophisticated implementations.
*
* IMPLEMENTATION NOTE - The DynaBean
* implementation class supplied to our constructor MUST have a one-argument
* constructor of its own that accepts a DynaClass. This is
* used to associate the DynaBean instance with this DynaClass.
*
* @version $Id$
*/
public class BasicDynaClass implements DynaClass, Serializable {
// ----------------------------------------------------------- Constructors
/**
* Construct a new BasicDynaClass with default parameters.
*/
public BasicDynaClass() {
this(null, null, null);
}
/**
* Construct a new BasicDynaClass with the specified parameters.
*
* @param name Name of this DynaBean class
* @param dynaBeanClass The implementation class for new instances
*/
public BasicDynaClass(final String name, final Class dynaBeanClass) {
this(name, dynaBeanClass, null);
}
/**
* Construct a new BasicDynaClass with the specified parameters.
*
* @param name Name of this DynaBean class
* @param dynaBeanClass The implementation class for new intances
* @param properties Property descriptors for the supported properties
*/
public BasicDynaClass(final String name, Class dynaBeanClass,
final DynaProperty[] properties) {
super();
if (name != null) {
this.name = name;
}
if (dynaBeanClass == null) {
dynaBeanClass = BasicDynaBean.class;
}
setDynaBeanClass(dynaBeanClass);
if (properties != null) {
setProperties(properties);
}
}
// ----------------------------------------------------- Instance Variables
/**
* The constructor of the dynaBeanClass that we will use
* for creating new instances.
*/
protected transient Constructor constructor = null;
/**
* The method signature of the constructor we will use to create
* new DynaBean instances.
*/
protected static Class[] constructorTypes = { DynaClass.class };
/**
* The argument values to be passed to the constructore we will use
* to create new DynaBean instances.
*/
protected Object[] constructorValues = { this };
/**
* The DynaBean implementation class we will use for
* creating new instances.
*/
protected Class dynaBeanClass = BasicDynaBean.class;
/**
* The "name" of this DynaBean class.
*/
protected String name = this.getClass().getName();
/**
* The set of dynamic properties that are part of this DynaClass.
*/
protected DynaProperty[] properties = new DynaProperty[0];
/**
* The set of dynamic properties that are part of this DynaClass,
* keyed by the property name. Individual descriptor instances will
* be the same instances as those in the properties list.
*/
protected HashMap propertiesMap = new HashMap();
// ------------------------------------------------------ DynaClass Methods
/**
* Return the name of this DynaClass (analogous to the
* getName() method of java.lang.ClassDynaClass implementation class to support
* different dynamic classes, with different sets of properties.
*
* @return the name of the DynaClass
*/
public String getName() {
return (this.name);
}
/**
* Return a property descriptor for the specified property, if it exists;
* otherwise, return null.
*
* @param name Name of the dynamic property for which a descriptor
* is requested
* @return The descriptor for the specified property
*
* @throws IllegalArgumentException if no property name is specified
*/
public DynaProperty getDynaProperty(final String name) {
if (name == null) {
throw new IllegalArgumentException
("No property name specified");
}
return propertiesMap.get(name);
}
/**
* Return an array of ProperyDescriptors for the properties
* currently defined in this DynaClass. If no properties are defined, a
* zero-length array will be returned.
*
* FIXME - Should we really be implementing
* getBeanInfo() instead, which returns property descriptors
* and a bunch of other stuff?
*
* @return the set of properties for this DynaClass
*/
public DynaProperty[] getDynaProperties() {
return (properties);
}
/**
* Instantiate and return a new DynaBean instance, associated
* with this DynaClass.
*
* @return A new DynaBean instance
* @throws IllegalAccessException if the Class or the appropriate
* constructor is not accessible
* @throws InstantiationException if this Class represents an abstract
* class, an array class, a primitive type, or void; or if instantiation
* fails for some other reason
*/
public DynaBean newInstance()
throws IllegalAccessException, InstantiationException {
try {
// Refind the constructor after a deserialization (if needed)
if (constructor == null) {
setDynaBeanClass(this.dynaBeanClass);
}
// Invoke the constructor to create a new bean instance
return ((DynaBean) constructor.newInstance(constructorValues));
} catch (final InvocationTargetException e) {
throw new InstantiationException
(e.getTargetException().getMessage());
}
}
// --------------------------------------------------------- Public Methods
/**
* Return the Class object we will use to create new instances in the
* newInstance() method. This Class MUST
* implement the DynaBean interface.
*
* @return The class of the {@link DynaBean}
*/
public Class getDynaBeanClass() {
return (this.dynaBeanClass);
}
// ------------------------------------------------------ Protected Methods
/**
* Set the Class object we will use to create new instances in the
* newInstance() method. This Class MUST
* implement the DynaBean interface.
*
* @param dynaBeanClass The new Class object
*
* @throws IllegalArgumentException if the specified Class does not
* implement the DynaBean interface
*/
protected void setDynaBeanClass(final Class dynaBeanClass) {
// Validate the argument type specified
if (dynaBeanClass.isInterface()) {
throw new IllegalArgumentException
("Class " + dynaBeanClass.getName() +
" is an interface, not a class");
}
if (!DynaBean.class.isAssignableFrom(dynaBeanClass)) {
throw new IllegalArgumentException
("Class " + dynaBeanClass.getName() +
" does not implement DynaBean");
}
// Identify the Constructor we will use in newInstance()
try {
this.constructor = dynaBeanClass.getConstructor(constructorTypes);
} catch (final NoSuchMethodException e) {
throw new IllegalArgumentException
("Class " + dynaBeanClass.getName() +
" does not have an appropriate constructor");
}
this.dynaBeanClass = dynaBeanClass;
}
/**
* Set the list of dynamic properties supported by this DynaClass.
*
* @param properties List of dynamic properties to be supported
*/
protected void setProperties(final DynaProperty[] properties) {
this.properties = properties;
propertiesMap.clear();
for (DynaProperty propertie : properties) {
propertiesMap.put(propertie.getName(), propertie);
}
}
}