/*
* 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.myfaces.shared_tomahawk.util;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import javax.faces.FacesException;
import javax.faces.context.FacesContext;
import javax.el.ExpressionFactory;
import java.io.InputStream;
import java.io.IOException;
import java.lang.reflect.Array;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.*;
/**
* @author Manfred Geiler (latest modification by $Author: werpu $)
* @author Anton Koinov
* @version $Revision: 805066 $ $Date: 2009-08-17 12:39:52 -0500 (Mon, 17 Aug 2009) $
*/
public final class ClassUtils
{
//~ Static fields/initializers -----------------------------------------------------------------
private static final Log log = LogFactory.getLog(ClassUtils.class);
public static final Class BOOLEAN_ARRAY_CLASS = boolean[].class;
public static final Class BYTE_ARRAY_CLASS = byte[].class;
public static final Class CHAR_ARRAY_CLASS = char[].class;
public static final Class SHORT_ARRAY_CLASS = short[].class;
public static final Class INT_ARRAY_CLASS = int[].class;
public static final Class LONG_ARRAY_CLASS = long[].class;
public static final Class FLOAT_ARRAY_CLASS = float[].class;
public static final Class DOUBLE_ARRAY_CLASS = double[].class;
public static final Class OBJECT_ARRAY_CLASS = Object[].class;
public static final Class BOOLEAN_OBJECT_ARRAY_CLASS = Boolean[].class;
public static final Class BYTE_OBJECT_ARRAY_CLASS = Byte[].class;
public static final Class CHARACTER_OBJECT_ARRAY_CLASS = Character[].class;
public static final Class SHORT_OBJECT_ARRAY_CLASS = Short[].class;
public static final Class INTEGER_OBJECT_ARRAY_CLASS = Integer[].class;
public static final Class LONG_OBJECT_ARRAY_CLASS = Long[].class;
public static final Class FLOAT_OBJECT_ARRAY_CLASS = Float[].class;
public static final Class DOUBLE_OBJECT_ARRAY_CLASS = Double[].class;
public static final Class STRING_OBJECT_ARRAY_CLASS = String[].class;
public static ClassLoaderExtension [] classLoadingExtensions = new ClassLoaderExtension[0];
public static final Map COMMON_TYPES = new HashMap(64);
static
{
COMMON_TYPES.put("byte", Byte.TYPE);
COMMON_TYPES.put("char", Character.TYPE);
COMMON_TYPES.put("double", Double.TYPE);
COMMON_TYPES.put("float", Float.TYPE);
COMMON_TYPES.put("int", Integer.TYPE);
COMMON_TYPES.put("long", Long.TYPE);
COMMON_TYPES.put("short", Short.TYPE);
COMMON_TYPES.put("boolean", Boolean.TYPE);
COMMON_TYPES.put("void", Void.TYPE);
COMMON_TYPES.put("java.lang.Object", Object.class);
COMMON_TYPES.put("java.lang.Boolean", Boolean.class);
COMMON_TYPES.put("java.lang.Byte", Byte.class);
COMMON_TYPES.put("java.lang.Character", Character.class);
COMMON_TYPES.put("java.lang.Short", Short.class);
COMMON_TYPES.put("java.lang.Integer", Integer.class);
COMMON_TYPES.put("java.lang.Long", Long.class);
COMMON_TYPES.put("java.lang.Float", Float.class);
COMMON_TYPES.put("java.lang.Double", Double.class);
COMMON_TYPES.put("java.lang.String", String.class);
COMMON_TYPES.put("byte[]", BYTE_ARRAY_CLASS);
COMMON_TYPES.put("char[]", CHAR_ARRAY_CLASS);
COMMON_TYPES.put("double[]", DOUBLE_ARRAY_CLASS);
COMMON_TYPES.put("float[]", FLOAT_ARRAY_CLASS);
COMMON_TYPES.put("int[]", INT_ARRAY_CLASS);
COMMON_TYPES.put("long[]", LONG_ARRAY_CLASS);
COMMON_TYPES.put("short[]", SHORT_ARRAY_CLASS);
COMMON_TYPES.put("boolean[]", BOOLEAN_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Object[]", OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Boolean[]", BOOLEAN_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Byte[]", BYTE_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Character[]", CHARACTER_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Short[]", SHORT_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Integer[]", INTEGER_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Long[]", LONG_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Float[]", FLOAT_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.Double[]", DOUBLE_OBJECT_ARRAY_CLASS);
COMMON_TYPES.put("java.lang.String[]", STRING_OBJECT_ARRAY_CLASS);
// array of void is not a valid type
}
/** utility class, do not instantiate */
private ClassUtils()
{
// utility class, disable instantiation
}
//~ Methods ------------------------------------------------------------------------------------
public static void addClassLoadingExtension(ClassLoaderExtension extension, boolean top) {
/**
* now at the first look this looks somewhat strange
* but to avoid synchronzed access we assign new native
* arrays to our static variable
* since primitive assignments are atomic in java and
* an array falls under the category primitive I assume we can
* work the lisp way of immutable data structures
*/
ClassLoaderExtension [] retVal = new ClassLoaderExtension[classLoadingExtensions.length+1];
ArrayList extensions = new ArrayList(classLoadingExtensions.length+1);
extensions.add(extension);
classLoadingExtensions = (ClassLoaderExtension []) extensions.toArray(retVal);
}
/**
* Tries a Class.loadClass with the context class loader of the current thread first and
* automatically falls back to the ClassUtils class loader (i.e. the loader of the
* myfaces.jar lib) if necessary.
*
* @param type fully qualified name of a non-primitive non-array class
* @return the corresponding Class
* @throws NullPointerException if type is null
* @throws ClassNotFoundException
*/
public static Class classForName(String type)
throws ClassNotFoundException
{
//we now assign the array to safekeep the reference on
// the local variable stack, that way
//we can avoid synchronisation calls
ClassLoaderExtension [] loaderPlugins = classLoadingExtensions;
int plugins = loaderPlugins.length;
for(int cnt = 0; cnt < loaderPlugins.length; cnt ++) {
ClassLoaderExtension extension = loaderPlugins[cnt];
Class retVal = extension.forName(type);
if(retVal != null) {
return retVal;
}
}
if (type == null) throw new NullPointerException("type");
try
{
// Try WebApp ClassLoader first
return Class.forName(type,
false, // do not initialize for faster startup
getContextClassLoader());
}
catch (ClassNotFoundException ignore)
{
// fallback: Try ClassLoader for ClassUtils (i.e. the myfaces.jar lib)
return Class.forName(type,
false, // do not initialize for faster startup
ClassUtils.class.getClassLoader());
}
}
/**
* Same as {@link #classForName(String)}, but throws a RuntimeException
* (FacesException) instead of a ClassNotFoundException.
*
* @return the corresponding Class
* @throws NullPointerException if type is null
* @throws FacesException if class not found
*/
public static Class simpleClassForName(String type)
{
try
{
return classForName(type);
}
catch (ClassNotFoundException e)
{
log.error("Class " + type + " not found", e);
throw new FacesException(e);
}
}
/**
* Similar as {@link #classForName(String)}, but also supports primitive types
* and arrays as specified for the JavaType element in the JavaServer Faces Config DTD.
*
* @param type fully qualified class name or name of a primitive type, both optionally
* followed by "[]" to indicate an array type
* @return the corresponding Class
* @throws NullPointerException if type is null
* @throws ClassNotFoundException
*/
public static Class javaTypeToClass(String type)
throws ClassNotFoundException
{
if (type == null) throw new NullPointerException("type");
// try common types and arrays of common types first
Class clazz = (Class) COMMON_TYPES.get(type);
if (clazz != null)
{
return clazz;
}
int len = type.length();
if (len > 2 && type.charAt(len - 1) == ']' && type.charAt(len - 2) == '[')
{
String componentType = type.substring(0, len - 2);
Class componentTypeClass = classForName(componentType);
return Array.newInstance(componentTypeClass, 0).getClass();
}
return classForName(type);
}
/**
* Same as {@link #javaTypeToClass(String)}, but throws a RuntimeException
* (FacesException) instead of a ClassNotFoundException.
*
* @return the corresponding Class
* @throws NullPointerException if type is null
* @throws FacesException if class not found
*/
public static Class simpleJavaTypeToClass(String type)
{
try
{
return javaTypeToClass(type);
}
catch (ClassNotFoundException e)
{
log.error("Class " + type + " not found", e);
throw new FacesException(e);
}
}
public static InputStream getResourceAsStream(String resource)
{
InputStream stream = getContextClassLoader()
.getResourceAsStream(resource);
if (stream == null)
{
// fallback
stream = ClassUtils.class.getClassLoader().getResourceAsStream(resource);
}
return stream;
}
/**
* @param resource Name of resource(s) to find in classpath
* @param defaultObject The default object to use to determine the class loader (if none associated with current thread.)
* @return Iterator over URL Objects
*/
public static Iterator getResources(String resource, Object defaultObject)
{
try
{
Enumeration resources = getCurrentLoader(defaultObject).getResources(resource);
List lst = new ArrayList();
while (resources.hasMoreElements())
{
lst.add(resources.nextElement());
}
return lst.iterator();
}
catch (IOException e)
{
log.error(e.getMessage(), e);
throw new FacesException(e);
}
}
public static Object newInstance(String type)
throws FacesException
{
if (type == null) return null;
return newInstance(simpleClassForName(type));
}
public static Object newInstance(String type, Class expectedType) throws FacesException
{
return newInstance(type, expectedType == null ? null : new Class[] {expectedType});
}
public static Object newInstance(String type, Class[] expectedTypes)
{
if (type == null)
return null;
Class clazzForName = simpleClassForName(type);
if(expectedTypes != null)
{
for (int i = 0, size = expectedTypes.length; i < size; i++)
{
if (!expectedTypes[i].isAssignableFrom(clazzForName))
{
throw new FacesException("'" + type + "' does not implement expected type '" + expectedTypes[i]
+ "'");
}
}
}
return newInstance(clazzForName);
}
public static Object newInstance(Class clazz)
throws FacesException
{
try
{
return clazz.newInstance();
}
catch(NoClassDefFoundError e)
{
log.error("Class : "+clazz.getName()+" not found.",e);
throw new FacesException(e);
}
catch (InstantiationException e)
{
log.error(e.getMessage(), e);
throw new FacesException(e);
}
catch (IllegalAccessException e)
{
log.error(e.getMessage(), e);
throw new FacesException(e);
}
}
public static Object convertToType(Object value, Class desiredClass)
{
if (value == null) return null;
try
{
ExpressionFactory expFactory = FacesContext.getCurrentInstance().getApplication().getExpressionFactory();
return expFactory.coerceToType(value, desiredClass);
}
catch (Exception e)
{
String message = "Cannot coerce " + value.getClass().getName()
+ " to " + desiredClass.getName();
log.error(message, e);
throw new FacesException(message, e);
}
}
/**
* Gets the ClassLoader associated with the current thread. Returns the class loader associated with
* the specified default object if no context loader is associated with the current thread.
*
* @param defaultObject The default object to use to determine the class loader (if none associated with current thread.)
* @return ClassLoader
*/
protected static ClassLoader getCurrentLoader(Object defaultObject)
{
ClassLoader loader = getContextClassLoader();
if(loader == null)
{
loader = defaultObject.getClass().getClassLoader();
}
return loader;
}
/**
* Gets the ClassLoader associated with the current thread. Includes a check for priviledges
* against java2 security to ensure no security related exceptions are encountered.
*
* @since 3.0.6
* @return ClassLoader
*/
public static ClassLoader getContextClassLoader()
{
if (System.getSecurityManager() != null)
{
try {
ClassLoader cl = AccessController.doPrivileged(new PrivilegedExceptionAction<ClassLoader>()
{
public ClassLoader run() throws PrivilegedActionException
{
return Thread.currentThread().getContextClassLoader();
}
});
return cl;
}
catch (PrivilegedActionException pae)
{
throw new FacesException(pae);
}
}
else
{
return Thread.currentThread().getContextClassLoader();
}
}
}