1 // NewInstance.java - create a new instance of a class by name.
2 // http://www.saxproject.org
3 // Written by Edwin Goei, edwingo@apache.org
4 // and by David Brownell, dbrownell@users.sourceforge.net
5 // NO WARRANTY! This class is in the Public Domain.
6 // $Id: NewInstance.java,v 1.4 2002/01/30 20:52:27 dbrownell Exp $
8 package org.xml.sax.helpers;
10 import java.lang.reflect.Method;
11 import java.lang.reflect.InvocationTargetException;
14 * Create a new instance of a class by name.
17 * <em>This module, both source code and documentation, is in the
18 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
19 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
20 * for further information.
23 * <p>This class contains a static method for creating an instance of a
24 * class from an explicit class name. It tries to use the thread's context
25 * ClassLoader if possible and falls back to using
26 * Class.forName(String).</p>
28 * <p>This code is designed to compile and run on JDK version 1.1 and later
29 * including versions of Java 2.</p>
31 * @author Edwin Goei, David Brownell
32 * @version 2.0.1 (sax2r2)
37 * Creates a new instance of the specified class name
39 * Package private so this code is not exposed at the API level.
41 static Object newInstance (ClassLoader classLoader, String className)
42 throws ClassNotFoundException, IllegalAccessException,
43 InstantiationException
46 if (classLoader == null) {
47 driverClass = Class.forName(className);
49 driverClass = classLoader.loadClass(className);
51 return driverClass.newInstance();
55 * Figure out which ClassLoader to use. For JDK 1.2 and later use
56 * the context ClassLoader.
58 static ClassLoader getClassLoader ()
63 m = Thread.class.getMethod("getContextClassLoader", null);
64 } catch (NoSuchMethodException e) {
65 // Assume that we are running JDK 1.1, use the current ClassLoader
66 return NewInstance.class.getClassLoader();
70 return (ClassLoader) m.invoke(Thread.currentThread(), null);
71 } catch (IllegalAccessException e) {
73 throw new UnknownError(e.getMessage());
74 } catch (InvocationTargetException e) {
75 // assert(e.getTargetException() instanceof SecurityException)
76 throw new UnknownError(e.getMessage());