/**
* Instantiate a JavaBean.
*
* @param classLoader the class-loader from which we should create the bean. If this is null, then
* the system class-loader is used.
* @param beanName the name of the bean within the class-loader. For example "sun.beanbox.foobah"
* @exception java.lang.ClassNotFoundException if the class of a serialized object could not be
* found.
* @exception java.io.IOException if an I/O error occurs.
*/
public static Object instantiate(ClassLoader cls, String beanName)
throws java.io.IOException, ClassNotFoundException {
java.io.InputStream ins;
java.io.ObjectInputStream oins = null;
Object result = null;
boolean serialized = false;
java.io.IOException serex = null;
// If the given classloader is null, we check if an
// system classloader is available and (if so)
// use that instead.
// Note that calls on the system class loader will
// look in the bootstrap class loader first.
if (cls == null) {
try {
cls = ClassLoader.getSystemClassLoader();
} catch (SecurityException ex) { // We're not allowed to access the system class loader.
// Drop through.
}
}
// Try to find a serialized object with this name
final String serName = beanName.replace('.', '/').concat(".ser");
final ClassLoader loader = cls;
ins =
(InputStream)
java.security.AccessController.doPrivileged(
new java.security.PrivilegedAction() {
public Object run() {
if (loader == null) return ClassLoader.getSystemResourceAsStream(serName);
else return loader.getResourceAsStream(serName);
}
});
if (ins != null) {
try {
if (cls == null) {
oins = new ObjectInputStream(ins);
} else {
oins = new ObjectInputStreamWithLoader(ins, cls);
}
result = oins.readObject();
serialized = true;
oins.close();
} catch (java.io.IOException ex) {
ins.close();
// Drop through and try opening the class. But remember
// the exception in case we can't find the class either.
serex = ex;
} catch (ClassNotFoundException ex) {
ins.close();
throw ex;
}
}
if (result == null) {
// No serialized object, try just instantiating the class
Class cl;
try {
if (cls == null) {
cl = Class.forName(beanName);
} else {
cl = cls.loadClass(beanName);
}
} catch (ClassNotFoundException ex) {
// There is no appropriate class. If we earlier tried to
// deserialize an object and got an IO exception, throw that,
// otherwise rethrow the ClassNotFoundException.
if (serex != null) {
throw serex;
}
throw ex;
}
/*
* Try to instantiate the class.
*/
try {
result = cl.newInstance();
} catch (Exception ex) {
// We have to remap the exception to one in our signature.
// But we pass extra information in the detail message.
throw new ClassNotFoundException("" + cl + " : " + ex);
}
}
if (result != null) { // Ok, if the result is an applet initialize it.
AppletStub stub = null;
if (result instanceof Applet) {
Applet applet = (Applet) result;
// Figure our the codebase and docbase URLs. We do this
// by locating the URL for a known resource, and then
// massaging the URL.
// First find the "resource name" corresponding to the bean
// itself. So a serialzied bean "a.b.c" would imply a
// resource name of "a/b/c.ser" and a classname of "x.y"
// would imply a resource name of "x/y.class".
final String resourceName;
if (serialized) {
// Serialized bean
resourceName = beanName.replace('.', '/').concat(".ser");
} else {
// Regular class
resourceName = beanName.replace('.', '/').concat(".class");
}
URL objectUrl = null;
URL codeBase = null;
URL docBase = null;
// Now get the URL correponding to the resource name.
final ClassLoader cloader = cls;
objectUrl =
(URL)
java.security.AccessController.doPrivileged(
new java.security.PrivilegedAction() {
public Object run() {
if (cloader == null) return ClassLoader.getSystemResource(resourceName);
else return cloader.getResource(resourceName);
}
});
// If we found a URL, we try to locate the docbase by taking
// of the final path name component, and the code base by taking
// of the complete resourceName.
// So if we had a resourceName of "a/b/c.class" and we got an
// objectURL of "file://bert/classes/a/b/c.class" then we would
// want to set the codebase to "file://bert/classes/" and the
// docbase to "file://bert/classes/a/b/"
if (objectUrl != null) {
String s = objectUrl.toExternalForm();
if (s.endsWith(resourceName)) {
int ix = s.length() - resourceName.length();
codeBase = new URL(s.substring(0, ix));
docBase = codeBase;
ix = s.lastIndexOf('/');
if (ix >= 0) {
docBase = new URL(s.substring(0, ix + 1));
}
}
}
// Setup a default context and stub.
BeansAppletContext context = new BeansAppletContext(applet);
stub = (AppletStub) new BeansAppletStub(applet, context, codeBase, docBase);
applet.setStub(stub);
// If it was deserialized then it was already init-ed.
// Otherwise we need to initialize it.
if (!serialized) {
// We need to set a reasonable initial size, as many
// applets are unhappy if they are started without
// having been explicitly sized.
applet.setSize(100, 100);
applet.init();
}
((BeansAppletStub) stub).active = true;
}
}
return result;
}
/**
* Load the applet into memory. Runs in a seperate (and interruptible) thread from the rest of the
* applet event processing so that it can be gracefully interrupted from things like HotJava.
*/
@SuppressWarnings("deprecation")
private void runLoader() {
if (status != APPLET_DISPOSE) {
showAppletStatus("notdisposed");
return;
}
dispatchAppletEvent(APPLET_LOADING, null);
// REMIND -- might be cool to visually indicate loading here --
// maybe do animation?
status = APPLET_LOAD;
// Create a class loader
loader = getClassLoader(getCodeBase(), getClassLoaderCacheKey());
// Load the archives if present.
// REMIND - this probably should be done in a separate thread,
// or at least the additional archives (epll).
String code = getCode();
// setup applet AppContext
// this must be called before loadJarFiles
setupAppletAppContext();
try {
loadJarFiles(loader);
applet = createApplet(loader);
} catch (ClassNotFoundException e) {
status = APPLET_ERROR;
showAppletStatus("notfound", code);
showAppletLog("notfound", code);
showAppletException(e);
return;
} catch (InstantiationException e) {
status = APPLET_ERROR;
showAppletStatus("nocreate", code);
showAppletLog("nocreate", code);
showAppletException(e);
return;
} catch (IllegalAccessException e) {
status = APPLET_ERROR;
showAppletStatus("noconstruct", code);
showAppletLog("noconstruct", code);
showAppletException(e);
// sbb -- I added a return here
return;
} catch (Exception e) {
status = APPLET_ERROR;
showAppletStatus("exception", e.getMessage());
showAppletException(e);
return;
} catch (ThreadDeath e) {
status = APPLET_ERROR;
showAppletStatus("death");
return;
} catch (Error e) {
status = APPLET_ERROR;
showAppletStatus("error", e.getMessage());
showAppletException(e);
return;
} finally {
// notify that loading is no longer going on
dispatchAppletEvent(APPLET_LOADING_COMPLETED, null);
}
// Fixed #4508194: NullPointerException thrown during
// quick page switch
//
if (applet != null) {
// Stick it in the frame
applet.setStub(this);
applet.hide();
add("Center", applet);
showAppletStatus("loaded");
validate();
}
}