mirror of git://gcc.gnu.org/git/gcc.git
81 lines
2.6 KiB
Java
81 lines
2.6 KiB
Java
// NewInstance.java - create a new instance of a class by name.
|
|
// http://www.saxproject.org
|
|
// Written by Edwin Goei, edwingo@apache.org
|
|
// and by David Brownell, dbrownell@users.sourceforge.net
|
|
// NO WARRANTY! This class is in the Public Domain.
|
|
|
|
// $Id: NewInstance.java,v 1.1.2.4 2002/01/29 21:34:14 dbrownell Exp $
|
|
|
|
package org.xml.sax.helpers;
|
|
|
|
import java.lang.reflect.Method;
|
|
import java.lang.reflect.InvocationTargetException;
|
|
|
|
/**
|
|
* Create a new instance of a class by name.
|
|
*
|
|
* <blockquote>
|
|
* <em>This module, both source code and documentation, is in the
|
|
* Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
|
|
* See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
|
|
* for further information.
|
|
* </blockquote>
|
|
*
|
|
* <p>This class contains a static method for creating an instance of a
|
|
* class from an explicit class name. It tries to use the thread's context
|
|
* ClassLoader if possible and falls back to using
|
|
* Class.forName(String).</p>
|
|
*
|
|
* <p>This code is designed to compile and run on JDK version 1.1 and later
|
|
* including versions of Java 2.</p>
|
|
*
|
|
* @author Edwin Goei, David Brownell
|
|
* @version 2.0.1 (sax2r2)
|
|
*/
|
|
class NewInstance {
|
|
|
|
/**
|
|
* Creates a new instance of the specified class name
|
|
*
|
|
* Package private so this code is not exposed at the API level.
|
|
*/
|
|
static Object newInstance (ClassLoader classLoader, String className)
|
|
throws ClassNotFoundException, IllegalAccessException,
|
|
InstantiationException
|
|
{
|
|
Class driverClass;
|
|
if (classLoader == null) {
|
|
driverClass = Class.forName(className);
|
|
} else {
|
|
driverClass = classLoader.loadClass(className);
|
|
}
|
|
return driverClass.newInstance();
|
|
}
|
|
|
|
/**
|
|
* Figure out which ClassLoader to use. For JDK 1.2 and later use
|
|
* the context ClassLoader.
|
|
*/
|
|
static ClassLoader getClassLoader ()
|
|
{
|
|
Method m = null;
|
|
|
|
try {
|
|
m = Thread.class.getMethod("getContextClassLoader", null);
|
|
} catch (NoSuchMethodException e) {
|
|
// Assume that we are running JDK 1.1, use the current ClassLoader
|
|
return NewInstance.class.getClassLoader();
|
|
}
|
|
|
|
try {
|
|
return (ClassLoader) m.invoke(Thread.currentThread(), null);
|
|
} catch (IllegalAccessException e) {
|
|
// assert(false)
|
|
throw new UnknownError(e.getMessage());
|
|
} catch (InvocationTargetException e) {
|
|
// assert(e.getTargetException() instanceof SecurityException)
|
|
throw new UnknownError(e.getMessage());
|
|
}
|
|
}
|
|
}
|