org.apache.cocoon.util
Class ClassUtils

java.lang.Object
  |
  +--org.apache.cocoon.util.ClassUtils

public class ClassUtils

extends java.lang.Object

A collection of class management utility methods.

Version:

CVS $Id: ClassUtils.java,v 1.5 2002/03/08 04:15:02 vgritsenko Exp $

Author:

Ricardo Rocha, Stefano Mazzocchi

Constructor Summary

ClassUtils()

Method Summary

static java.lang.ClassLoader	getClassLoader() Return the context classloader.
static java.net.URL	getResource(java.lang.String resource) Return a resource URL.
static boolean	implementsInterface(java.lang.Class class1, java.lang.Class iface) Tests if a class implements a given interface
static boolean	implementsInterface(java.lang.String className, java.lang.String iface) Tests if a class implements a given interface
static long	lastModified(java.lang.Class aClass) Determine the last modification date for this class file or its enclosing library
static java.lang.Class	loadClass(java.lang.String className) Load a class given its name.
static java.lang.Object	newInstance(java.lang.String className) Create a new instance given a class name
static java.lang.String	which(java.lang.Class aClass) Gets the absolute pathname of the class file containing the specified class name, as prescribed by the current classpath.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ClassUtils

public ClassUtils()

Method Detail

newInstance

public static java.lang.Object newInstance(java.lang.String className)
                                    throws java.lang.Exception

Create a new instance given a class name

Parameters:

className - A class name

Returns:

A new instance

Throws:

java.lang.Exception - If an instantiation error occurs

loadClass

public static java.lang.Class loadClass(java.lang.String className)
                                 throws java.lang.ClassNotFoundException

Load a class given its name. BL: We wan't to use a known ClassLoader--hopefully the heirarchy is set correctly.

Parameters:

className - A class name

Returns:

The class pointed to by className

Throws:

java.lang.ClassNotFoundException - If a loading error occurs

getResource

public static java.net.URL getResource(java.lang.String resource)
                                throws java.net.MalformedURLException

Return a resource URL. BL: if this is command line operation, the classloading issues are more sane. During servlet execution, we explicitly set the ClassLoader.

Returns:

The context classloader.

Throws:

java.net.MalformedURLException - If a loading error occurs

getClassLoader

public static java.lang.ClassLoader getClassLoader()

Return the context classloader. BL: if this is command line operation, the classloading issues are more sane. During servlet execution, we explicitly set the ClassLoader.

Returns:

The context classloader.

implementsInterface

public static boolean implementsInterface(java.lang.String className,
                                          java.lang.String iface)
                                   throws java.lang.Exception

Tests if a class implements a given interface

Returns:

true if class implements given interface.

implementsInterface

public static boolean implementsInterface(java.lang.Class class1,
                                          java.lang.Class iface)

Tests if a class implements a given interface

Returns:

true if class implements given interface.

lastModified

public static long lastModified(java.lang.Class aClass)
                         throws java.io.IOException,
                                java.lang.IllegalArgumentException

Determine the last modification date for this class file or its enclosing library

Parameters:

aClass - A class whose last modification date is queried

Returns:

The time the given class was last modified

Throws:

java.io.IOException - IOError

java.lang.IllegalArgumentException - The class was not loaded from a file or directory

which

public static java.lang.String which(java.lang.Class aClass)

Gets the absolute pathname of the class file containing the specified class name, as prescribed by the current classpath.

Parameters:

aClass - Name of the class.