/*
* The Apache Software License, Version 1.1
*
* Copyright (c) 1999 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* 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
* <http://www.apache.org/>.
*
*/
package org.jbpm.jpdl.el.impl;
import java.beans.BeanInfo;
import java.beans.EventSetDescriptor;
import java.beans.IndexedPropertyDescriptor;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.HashMap;
import java.util.Map;
import org.jbpm.jpdl.el.ELException;
/**
*
* <p>
* Manages the BeanInfo for one class - contains the BeanInfo, and also a
* mapping from property name to BeanInfoProperty. There are also static methods
* for accessing the BeanInfoManager for a class - those mappings are cached
* permanently so that once the BeanInfoManager is calculated, it doesn't have
* to be calculated again.
*
* @author Nathan Abramson - Art Technology Group
* @author Tom Baeyens - JBoss
* @version $Change: 181181 $$DateTime: 2001/06/26 09:55:09 $$Author$
*/
public class BeanInfoManager {
// -------------------------------------
// Properties
// -------------------------------------
// property beanClass
Class mBeanClass;
public Class getBeanClass() {
return mBeanClass;
}
// -------------------------------------
// Member variables
// -------------------------------------
// The BeanInfo
BeanInfo mBeanInfo;
// Mapping from property name to BeanInfoProperty
Map mPropertyByName;
// Mapping from property name to BeanInfoIndexedProperty
Map mIndexedPropertyByName;
// Mapping from method name to BeanMethod
Map mMethodByName;
// Mapping from event set name to event set descriptor
Map mEventSetByName;
// Flag if this is initialized
boolean mInitialized;
// The global mapping from class to BeanInfoManager
static Map mBeanInfoManagerByClass = new HashMap();
// -------------------------------------
/**
*
* Constructor
*/
BeanInfoManager(Class pBeanClass) {
mBeanClass = pBeanClass;
}
// -------------------------------------
/**
*
* Returns the BeanInfoManager for the specified class
*/
public static BeanInfoManager getBeanInfoManager(Class pClass) {
BeanInfoManager ret = (BeanInfoManager) mBeanInfoManagerByClass.get(pClass);
if (ret == null) {
ret = createBeanInfoManager(pClass);
}
return ret;
}
// -------------------------------------
/**
*
* Creates and registers the BeanInfoManager for the given class if it isn't
* already registered.
*/
static synchronized BeanInfoManager createBeanInfoManager(Class pClass) {
// Because this method is synchronized statically, the
// BeanInfoManager is not initialized at this time (otherwise it
// could end up being a bottleneck for the entire system). It is
// put into the map in an uninitialized state. The first time
// someone tries to use it, it will be initialized (with proper
// synchronizations in place to make sure it is only initialized
// once).
BeanInfoManager ret = (BeanInfoManager) mBeanInfoManagerByClass.get(pClass);
if (ret == null) {
ret = new BeanInfoManager(pClass);
mBeanInfoManagerByClass.put(pClass, ret);
}
return ret;
}
// -------------------------------------
/**
*
* Returns the BeanInfoProperty for the specified property in the given class,
* or null if not found.
*/
public static BeanInfoProperty getBeanInfoProperty(Class pClass, String pPropertyName, Logger pLogger) throws ELException {
return getBeanInfoManager(pClass).getProperty(pPropertyName, pLogger);
}
// -------------------------------------
/**
*
* Returns the BeanInfoIndexedProperty for the specified property in the given
* class, or null if not found.
*/
public static BeanInfoIndexedProperty getBeanInfoIndexedProperty(Class pClass, String pIndexedPropertyName, Logger pLogger) throws ELException {
return getBeanInfoManager(pClass).getIndexedProperty(pIndexedPropertyName, pLogger);
}
public static BeanMethod getBeanMethod(Class pClass, String indexStr, Logger logger) throws ELException {
return getBeanInfoManager(pClass).getBeanMethod(indexStr,logger);
}
// -------------------------------------
/**
*
* Makes sure that this class has been initialized, and synchronizes the
* initialization if it's required.
*/
void checkInitialized(Logger pLogger) throws ELException {
if (!mInitialized) {
synchronized (this) {
if (!mInitialized) {
initialize(pLogger);
mInitialized = true;
}
}
}
}
// -------------------------------------
/**
*
* Initializes by mapping property names to BeanInfoProperties
*/
void initialize(Logger pLogger) throws ELException {
try {
mBeanInfo = Introspector.getBeanInfo(mBeanClass);
mPropertyByName = new HashMap();
mIndexedPropertyByName = new HashMap();
mMethodByName = new HashMap();
PropertyDescriptor[] pds = mBeanInfo.getPropertyDescriptors();
for (int i = 0; pds != null && i < pds.length; i++) {
// Treat as both an indexed property and a normal property
PropertyDescriptor pd = pds[i];
if (pd instanceof IndexedPropertyDescriptor) {
IndexedPropertyDescriptor ipd = (IndexedPropertyDescriptor) pd;
Method readMethod = getPublicMethod(ipd.getIndexedReadMethod());
Method writeMethod = getPublicMethod(ipd.getIndexedWriteMethod());
BeanInfoIndexedProperty property = new BeanInfoIndexedProperty(readMethod, writeMethod, ipd);
mIndexedPropertyByName.put(ipd.getName(), property);
}
Method readMethod = getPublicMethod(pd.getReadMethod());
Method writeMethod = getPublicMethod(pd.getWriteMethod());
BeanInfoProperty property = new BeanInfoProperty(readMethod, writeMethod, pd);
mPropertyByName.put(pd.getName(), property);
}
mEventSetByName = new HashMap();
EventSetDescriptor[] esds = mBeanInfo.getEventSetDescriptors();
for (int i = 0; esds != null && i < esds.length; i++) {
EventSetDescriptor esd = esds[i];
mEventSetByName.put(esd.getName(), esd);
}
} catch (IntrospectionException exc) {
if (pLogger.isLoggingWarning()) {
pLogger.logWarning(Constants.EXCEPTION_GETTING_BEANINFO, exc, mBeanClass.getName());
}
}
// parsing the bean methods
Class scannedClass = mBeanClass;
while (scannedClass!=null) {
Method[] methods = scannedClass.getDeclaredMethods();
for (int i=0; i<methods.length; i++) {
Method method = methods[i];
if ( (!mMethodByName.containsKey(method.getName()))
&& ( (method.getParameterTypes()==null)
|| (method.getParameterTypes().length==0)
)
) {
mMethodByName.put(method.getName(), new BeanMethod(method));
}
}
scannedClass = scannedClass.getSuperclass();
}
}
// -------------------------------------
/**
*
* Returns the BeanInfo for the class
*/
BeanInfo getBeanInfo(Logger pLogger) throws ELException {
checkInitialized(pLogger);
return mBeanInfo;
}
// -------------------------------------
/**
*
* Returns the BeanInfoProperty for the given property name, or null if not
* found.
*/
public BeanInfoProperty getProperty(String pPropertyName, Logger pLogger) throws ELException {
checkInitialized(pLogger);
return (BeanInfoProperty) mPropertyByName.get(pPropertyName);
}
// -------------------------------------
/**
*
* Returns the BeanInfoIndexedProperty for the given property name, or null if
* not found.
*/
public BeanInfoIndexedProperty getIndexedProperty(String pIndexedPropertyName, Logger pLogger) throws ELException {
checkInitialized(pLogger);
return (BeanInfoIndexedProperty) mIndexedPropertyByName.get(pIndexedPropertyName);
}
public BeanMethod getBeanMethod(String pMethodName, Logger pLogger) throws ELException {
checkInitialized(pLogger);
return (BeanMethod) mMethodByName.get(pMethodName);
}
// -------------------------------------
/**
*
* Returns the EventSetDescriptor for the given event set name, or null if not
* found.
*/
public EventSetDescriptor getEventSet(String pEventSetName, Logger pLogger) throws ELException {
checkInitialized(pLogger);
return (EventSetDescriptor) mEventSetByName.get(pEventSetName);
}
// -------------------------------------
// Finding the public version of a method - if a PropertyDescriptor
// is obtained for a non-public class that implements a public
// interface, the read/write methods will be for the class, and
// therefore inaccessible. To correct this, a version of the same
// method must be found in a superclass or interface.
// -------------------------------------
/**
*
* Returns a publicly-accessible version of the given method, by searching for
* a public declaring class.
*/
static Method getPublicMethod(Method pMethod) {
if (pMethod == null) {
return null;
}
// See if the method is already available from a public class
Class cl = pMethod.getDeclaringClass();
if (Modifier.isPublic(cl.getModifiers())) {
return pMethod;
}
// Otherwise, try to find a public class that declares the method
Method ret = getPublicMethod(cl, pMethod);
if (ret != null) {
return ret;
} else {
return pMethod;
}
}
// -------------------------------------
/**
*
* If the given class is public and has a Method that declares the same name
* and arguments as the given method, then that method is returned. Otherwise
* the superclass and interfaces are searched recursively.
*/
static Method getPublicMethod(Class pClass, Method pMethod) {
// See if this is a public class declaring the method
if (Modifier.isPublic(pClass.getModifiers())) {
try {
Method m;
try {
m = pClass.getDeclaredMethod(pMethod.getName(), pMethod.getParameterTypes());
} catch (java.security.AccessControlException ex) {
// kludge to accommodate J2EE RI's default settings
// TODO: see if we can simply replace
// getDeclaredMethod() with getMethod() ...?
m = pClass.getMethod(pMethod.getName(), pMethod.getParameterTypes());
}
if (Modifier.isPublic(m.getModifiers())) {
return m;
}
} catch (NoSuchMethodException exc) {
}
}
// Search the interfaces
{
Class[] interfaces = pClass.getInterfaces();
if (interfaces != null) {
for (int i = 0; i < interfaces.length; i++) {
Method m = getPublicMethod(interfaces[i], pMethod);
if (m != null) {
return m;
}
}
}
}
// Search the superclass
{
Class superclass = pClass.getSuperclass();
if (superclass != null) {
Method m = getPublicMethod(superclass, pMethod);
if (m != null) {
return m;
}
}
}
return null;
}
// -------------------------------------
}