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Types that extend and augment the Java Collections Framework.
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001-2004 The Apache Software Foundation. All rights
* reserved.
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* modification, are permitted provided that the following conditions
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*
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* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
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* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
*
* Creates a Factory that will return a clone of the same prototype object
* each time the factory is used. The prototype will be cloned using one of these
* techniques (in order):
*
* - public clone method
*
- public copy constructor
*
- serialization clone
*
*
* @param prototype the object to clone each time in the factory
* @return the prototype factory
* @throws IllegalArgumentException if the prototype is null
* @throws IllegalArgumentException if the prototype cannot be cloned
*/
public static Factory getInstance(Object prototype) {
if (prototype == null) {
return ConstantFactory.NULL_INSTANCE;
}
try {
Method method = prototype.getClass().getMethod("clone", null);
return new PrototypeCloneFactory(prototype, method);
} catch (NoSuchMethodException ex) {
try {
prototype.getClass().getConstructor(new Class[] { prototype.getClass()});
return new InstantiateFactory(
prototype.getClass(),
new Class[] { prototype.getClass()},
new Object[] { prototype });
} catch (NoSuchMethodException ex2) {
if (prototype instanceof Serializable) {
return new PrototypeSerializationFactory((Serializable) prototype);
}
}
}
throw new IllegalArgumentException("The prototype must be cloneable via a public clone method");
}
/**
* Constructor that performs no validation.
* Use getInstance if you want that.
*/
private PrototypeFactory() {
}
// PrototypeCloneFactory
//-----------------------------------------------------------------------
/**
* PrototypeCloneFactory creates objects by copying a prototype using the clone method.
*/
static class PrototypeCloneFactory implements Factory, Serializable {
/** The serial version */
static final long serialVersionUID = 5604271422565175555L;
/** The object to clone each time */
private final Object iPrototype;
/** The method used to clone */
private transient Method iCloneMethod;
/**
* Constructor to store prototype.
*/
private PrototypeCloneFactory(Object prototype, Method method) {
super();
iPrototype = prototype;
iCloneMethod = method;
}
/**
* Find the Clone method for the class specified.
*/
private void findCloneMethod() {
try {
iCloneMethod = iPrototype.getClass().getMethod("clone", null);
} catch (NoSuchMethodException ex) {
throw new IllegalArgumentException("PrototypeCloneFactory: The clone method must exist and be public ");
}
}
/**
* Return clone of prototype
*/
public Object create() {
// needed for post-serialization
if (iCloneMethod == null) {
findCloneMethod();
}
try {
return iCloneMethod.invoke(iPrototype, null);
} catch (IllegalAccessException ex) {
throw new FunctorException("PrototypeCloneFactory: Clone method must be public", ex);
} catch (InvocationTargetException ex) {
throw new FunctorException("PrototypeCloneFactory: Clone method threw an exception", ex);
}
}
}
// PrototypeSerializationFactory
//-----------------------------------------------------------------------
/**
* PrototypeSerializationFactory creates objects by cloning a prototype using serialization.
*/
static class PrototypeSerializationFactory implements Factory, Serializable {
/** The serial version */
static final long serialVersionUID = -8704966966139178833L;
/** The object to clone via serialization each time */
private final Serializable iPrototype;
/**
* Constructor to store prototype
*/
private PrototypeSerializationFactory(Serializable prototype) {
super();
iPrototype = prototype;
}
/**
* Return clone of prototype by serialization
*/
public Object create() {
ByteArrayOutputStream baos = new ByteArrayOutputStream(512);
ByteArrayInputStream bais = null;
try {
ObjectOutputStream out = new ObjectOutputStream(baos);
out.writeObject(iPrototype);
bais = new ByteArrayInputStream(baos.toByteArray());
ObjectInputStream in = new ObjectInputStream(bais);
return in.readObject();
} catch (ClassNotFoundException ex) {
throw new FunctorException(ex);
} catch (IOException ex) {
throw new FunctorException(ex);
} finally {
try {
if (bais != null) {
bais.close();
}
} catch (IOException ignored) {
}
try {
if (baos != null) {
baos.close();
}
} catch (IOException ignored) {
}
}
}
}
}