Reflection to load a class
Hi,
I am newbie to JAVA. Can anyone tell me how to use reflection to load a class and call a method on the created object through reflection API?
Thank you very much for the reply.
But this is the exercise I have to do. I started
learning JAVA since 15 days. Even if this is
difficult, I ll try to grab whatever possible. Please
gimme a very simple example or good links.
Thanks again,
BasavFair enough. Don't say I didn't warn you
Class clazz = Class.forName("com.mydomain.myapp.MyClass";
Object obj = clazz.newInstance();
Method performAction = clazz.getDeclaredMethod("doSomething", new Class[0] );
Object result = performAction.invoke(obj, new Object[0]);Don't bother asking for any explanation of what it means, or for any help when it doesn't work. You've been coding a whole 15 days, you're obviously ready for this by now, and should know exactly what it's all about and how to fix any problems that arise
Similar Messages
-
Loading a class via reflection without knowing the full qualified path ?
Hi there
I d like to load a class via reflection and call the constructor of the class object. My problem is that I dont know the full qulified name e.g. org.xyz.Classname bur only the Classname.
I tried different things but none seem to work:
1. Class c = Class.forName("Classname"); //does not suffice, full qualified name required
2. ClassLoader classloader = java.lang.ClassLoader.getSystemClassLoader();
try {
Class cl = classloader.loadClass(stripFileType(Filename));//if i do not pass the full qualified name i get a ClassNotFoundException
3. I tried to consruct a class object with my own classloader , calling:
Class cl = super.defineClass(null, b, 0, b.length ); b is of type byte[]This almost works. I get a class Object without knowing the full qulified path. I can transform a filename into a raw array of bytes and I get the class out of it. But there is still a problem: If there are more than on classes defined in the same textfile I get an InvocationTargetException.
It looks like this:
package org.eml.adaptiveUI.demo;
import com.borland.jbcl.layout.*;
import java.awt.*;
import org.eml.adaptiveUI.layout.*;
import javax.swing.*;
import java.awt.event.*;
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2003</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
public class twoButtons extends JFrame {
SPanel sPanel1 = new SPanel();
JButton jButton1 = new JButton();
GridBagLayout gridBagLayout1 = new GridBagLayout();
GridBagLayout gridBagLayout2 = new GridBagLayout();
public twoButtons() throws HeadlessException {
try {
jbInit();
catch(Exception e) {
e.printStackTrace();
public static void main(String args[]){
twoButtons twob = new twoButtons();
twob.pack();
twob.show();
private void jbInit() throws Exception {
this.getContentPane().setLayout(gridBagLayout1);
jButton1.setText("button 1");
jButton1.addActionListener(new TransformationDemo_jButton1_actionAdapter(this));
this.getContentPane().add(sPanel1, new GridBagConstraints(0, 0, 1, 1, 1.0, 1.0
,GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(57, 52, 94, 108), 35, 44));
sPanel1.add(jButton1, new GridBagConstraints(0, 0, 1, 1, 0.0, 0.0
,GridBagConstraints.CENTER, GridBagConstraints.NONE, new Insets(5, 41, 0, 0), 0, 0));
void jButton1_actionPerformed(ActionEvent e) {
System.out.println("button 1 source: " + e.getSource());
System.out.println("d: " + e.getID());
System.out.println("/n commmand: " + e.getActionCommand());
class TransformationDemo_jButton1_actionAdapter implements java.awt.event.ActionListener {
twoButtons adaptee;
TransformationDemo_jButton1_actionAdapter(twoButtons adaptee) {
this.adaptee = adaptee;
public void actionPerformed(ActionEvent e) {
adaptee.jButton1_actionPerformed(e);
}As you can see there is the class TransformationDemo_jButton1_actionAdapter class defined in the same classfile. The problem is now that the twoButtons constructor calls the TransfomationDemo_jButton1_actionAdapter constructor and this leads to InvocationTargetException. I dont know if this is a java bug because it should be possible.
Can you help me?hi thanks at first,
the thing you mentioned could be a problem, but I dont think it is.
If I have the full qualified name (which I havent) then everything goes normal. I only have to load the "twoButtons" class and not the other (actionadapter class), so I dont think this is the point. In this case the twoButtons constructor constructs an object of the actionadapter class and everything goes well. The bad thing is though that I do not have the full qulified name :(
Invocation target exception tells me (in own words): Tried to acces the constructor of the actionadapter class (which is not public) out of class reflectionTest class .
reflectionTest is the class where the reflection stuff happens and the twoButttons class is defineClass() ed.
The problem is, only twoButtons class has the rights to call methods from the actionadapter class, the reflection class does not. BUT: I do not call the actionadapter methods from the reflection class. I call them only from the twoButtons class.
I hope somebody understands my problem :) -
How to load a class dynamically (via reflection) in a jsf-component
Hi all,
I am writing my own jsf component and I would like to do it generically. Therefore I have an attribute, where the developer can pass a fully qualified classname, which I want to use to instantiate. But I have a Problem with the classloaders, everytime I get a ClassNotFound-Exception during debugging.
Does anybody know how it is possible, to to get the most parent classloader?
Currently I am even not able to load a class, which is in the same package like all other compontent-classes.
Thank you very much in advance
ThomasWithin web applications, I believe it is recommended to use Thread.getContextClassLoader(). Keep in mind that web applications require different classloader semantics than regular Java applications. The class loader which gets resources from the WAR is favored over others, even when this violates the normal class loading conventions.
-
How to load a Class Dynamically?
hi,
I have the following problem.I am trying to load a class dynamically.For this I am using ClassLoader and its Loadclass method.My code is like this,
File file = filechooser.getSelectedFile();
ClassLoader Cload = this.getClass().getClassLoader();
String tempClsname= file.getName();
Class cd =Cload.loadClass(tempClsname);
Object ob =(Object)cd.newInstance();
showMethods(ob);
In showMethods what i am doing is getting the public methods of the dynamically loaded class,
void showMethods(Object o){
Class c = o.getClass();
System.out.println(c.getName());
vecList = new Vector();
Method theMethods[] = c.getDeclaredMethods();
for (int i = 0; i < theMethods.length; i++) {
if(theMethods.getModifiers()==java.lang.reflect.Modifier.PUBLIC)
String methodString = theMethods.getName();
System.out.println(methodString);
vecList.addElement(methodString);
allmthdlst.setListData(vecList);
Now whenever i work with this i m getting a runtime error of CLASS NOT FOUND Exception..I know its because of Classpath..But i don't know how to resolve it??pls help me in this regard...
Also previously this code was working with java files in the directory in which this java file was present..How to make it work for java file in some other directory..pls help me in this regard...
Thanks in advance..You sure didn't need to post this twice.
http://forum.java.sun.com/thread.jsp?thread=522234&forum=31&message=2498659
When you post code, please use [code] and [/code] tags as described in Formatting Help on the message entry page. It makes it much easier to read and prevents accidental markup from array indices like [i].
You resolve this problem by ensuring the class is in the classpath and you refer to it by its full name.
§ -
How to load a .class file dynamically?
Hello World ;)
Does anyone know, how I can create an object of a class, that was compiled during the runtime?
The facts:
- The user puts a grammar in. Saved to file. ANTLR generates Scanner and Parser (Java Code .java)
- I compile these file, so XYScanner.class and XYParser.class are available.
- Now I want to create an object of XYScanner (the classnames are not fixed, but I know the filename). I tried to call the constructor of XYScanner (using reflection) but nothing works and now I am really despaired!
Isn't there any way to instantiate the class in a way like
Class c = Class.forName("/home/mark/XYScanner");
c scan = new c("input.txt");
The normal call would be:
XYLexer lex = new XYLexer(new ANTLRFileStream("input.txt"));The problem using reflection is now that the parameter is a ANTLRFileStream, not only an Integer, as in this example shown:
Class cls = Class.forName("method2");
Class partypes[] = new Class[2];
partypes[0] = Integer.TYPE;
partypes[1] = Integer.TYPE;
Method meth = cls.getMethod("add", partypes);
method2 methobj = new method2();
Object arglist[] = new Object[2];
arglist[0] = new Integer(37);
arglist[1] = new Integer(47);
Object retobj = meth.invoke(methobj, arglist);
Integer retval = (Integer)retobj;
System.out.println(retval.intValue());Has anyone an idea? Thanks for each comment in advance!!!Dump all of your class files into a directory.
Use the File class to list all files and iterateover
the files.NastyNot really, when you are dynamically creating code, I would expect the output to be centralized, not spread out all over the place.
>
Use a URLClassloader to load the URL that isobtained
for each file with file.toURI().toURL()(file.toURL()
is depricated in 1.6)Wrong, the URL you give it must be that of the
directory, not the class file.No, I did this quite recently, you can give it a specific class file to load.
>
Load all of the classes in this directory, thatway
any anonymous classes are loaded as well.Anonymous classes automatically loaded when the real
one isIt can't load it if it doesn't know where the code is. Since you haven't used a URL classloader to load once class file at a time, you would never encounter this. But if you loaded a class file that had an anonymous classfile it needed, would it know where to look for it?
>
From this point you should be able to just get a
class with Class.forName(name)No. Class.forName uses the classloader of the class
it's called in, which will be the system classloader.
It won't find classes loaded by a URLClassLoader.got me there. -
LoadClass (error loading a class which extends other class at run-time)
Hey!
I'm using the Reflection API
I load a class called 'SubClass' which exists in a directory called 'subdir' at run-time from my program
CustomClassLoader loader = new CustomClassLoader();
Class classRef = loader.loadClass("SubClass");
class CustomClassLoader extends ClassLoader. I have defined 'findClass(String className)' method in CustomClassLoader.
This is what 'findClass(String className)' returns:
defineClass (className,byteArray,0,byteArray.length);
'byteArray' is of type byte[] and has the contents of subdir/SubClass.
the problem:
The program runs fine if SubClass does not extend any class.
If however, SubClass extends another class, the program throws a NoClassDefFoundError. How is it conceptually different?
Help appreciated in Advance..
Thanks!Because i'm a newbie to the Reflection thing, i'm notI don't see reflection anywhere. All I see is class loading.
sure what role does the superclass play when i'm
trying to load the derived class and how to get away
with the errorWell... hint: all the superclass's stuff is not copied into the subclass.
I am quite sure it fails to load the superclass because of classpath issues. -
Loading a class not on classpath
how can we load a class not on classpath?
uddinr0121 wrote:
try this
private void addArchive(File jarFile) throws IOException {
URL u = jarFile.toURI().toURL();
URLClassLoader sysloader = (URLClassLoader) ClassLoader.getSystemClassLoader();
Class<?> sysclass = URLClassLoader.class;
try {
Method method = sysclass.getDeclaredMethod("addURL", parameters);
method.setAccessible(true);
method.invoke(sysloader, new Object[]{u});
} catch (Throwable t) {
t.printStackTrace();
}this will add the jar file to the classpath after which you should be able to invoke using Class.forName()
hope this helpsThat's a horrible solution, when you can just create a new URLClassLoader and use that to load the class.
Adding it to the system classpath with reflection trickery is not really a clean solution to that. -
Can't load any classes from infobus.jar (WL 6.0 SP1)
Hi,
I am deploying an .ear file, which has one .war file in it. The war file, has
infobus.jar, inside it under \WEB-INF\lib. Whenever in my servlet code I try to
load a class from infobus.jar, I get the following exception :
About to load class javax.infobus.InfoBusDataConsumer<<<<<<<<<<java.lang.ClassNotFoundException: InfoBusDataConsumer
at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:178)
at weblogic.utils.classloaders.ChangeAwareClassLoader.findClass(ChangeAwareClassLoader.java:45)
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at java.lang.ClassLoader.loadClass(ClassLoader.java:253)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:313)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:120)
at XDILoginForm.init(XDILoginForm.java:99)
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at weblogic.servlet.internal.ServletStubImpl.createInstances(ServletStubImpl.java:581)
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at weblogic.servlet.internal.WebAppServletContext.preloadServlet(WebAppServletContext.java:1078)
at weblogic.servlet.internal.WebAppServletContext.preloadServlets(WebAppServletContext.java:1022)
at weblogic.servlet.internal.HttpServer.loadWARContext(HttpServer.java:499)
at weblogic.servlet.internal.HttpServer.loadWebApp(HttpServer.java:421)
at weblogic.j2ee.WebAppComponent.deploy(WebAppComponent.java:74)
at weblogic.j2ee.Application.deploy(Application.java:175)
at weblogic.j2ee.J2EEService.deployApplication(J2EEService.java:173)
at weblogic.management.mbeans.custom.Application.setLocalDeployed(Application.java:217)
at weblogic.management.mbeans.custom.Application.setDeployed(Application.java:187)
at java.lang.reflect.Method.invoke(Native Method)
at weblogic.management.internal.DynamicMBeanImpl.invokeSetter(DynamicMBeanImpl.java:1136)
at weblogic.management.internal.DynamicMBeanImpl.setAttribute(DynamicMBeanImpl.java:773)
at weblogic.management.internal.DynamicMBeanImpl.setAttribute(DynamicMBeanImpl.java:750)
at weblogic.management.internal.ConfigurationMBeanImpl.setAttribute(ConfigurationMBeanImpl.java:256)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1356)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1331)
at weblogic.management.internal.ConfigurationMBeanImpl.updateConfigMBeans(ConfigurationMBeanImpl.java:318)
at weblogic.management.internal.ConfigurationMBeanImpl.setAttribute(ConfigurationMBeanImpl.java:259)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1356)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1331)
at weblogic.management.internal.MBeanProxy.setAttribute(MBeanProxy.java:291)
at weblogic.management.internal.MBeanProxy.invoke(MBeanProxy.java:173)
at $Proxy7.setDeployed(Unknown Source)
at weblogic.management.console.pages._panels._mbean._application._jspService(_application.java:303)
at weblogic.servlet.jsp.JspBase.service(JspBase.java:27)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:213)
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at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
But if I put the infobus.jar on system classpath , everything works out fine.
Can somebody tell me, what is going onGseel is right: you try to instantiate an EJB with the BDK.
Enterprise Java Beans are totally different from graphical/GUI beans. EJBs are thought for dealing with business logic like accessing a database, ldap directory and so on. They run on a application server (simply speaking - a java enabled webserver) and do some processing to handle user requests. Enterprise Java Beans usually don't interact directly with the user, they only do the work in the background and forward their results, which are then rendered for the user. Typically they are employed for handling web requests (a user with a browser), but they can also be used for awt/swing applications. Though - let me repeat - they don't appear visually on the screen.
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If you want to run your been you need an application server (your bean is pre-packaged for the Bea Weblogic app-server). If you want to do something graphical, you'll need to search for GUI beans.
dani3l -
Help with loading dynamic classes ..need help please
i'm trying to design a program where by i can load dynamic classes
the problem i'm getting is that only one class is loading.
classes are loaded by their names,and index numbers of public methods from a linklist
.When the program runs only the first class is ever loaded and only the methods of that class ..
help please
//class loader
import java.lang.reflect.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;
public class Test2 extends Thread
public Class c;
public Class Ray;
public Class[] x;
public static Object object = null;
public Method[] theMethods;
public static Method[] method,usemethod;
public int methodcount;
public static int MethodCt;
public static JList list;
public Method[] startClass(String SetMethodName)
try
c = Class.forName(SetMethodName);
object = c.newInstance();
theMethods = c.getDeclaredMethods();
// number of methods
//methodcount = theMethods.length;
catch (Exception e)
e.printStackTrace();
// return the array then invoke the particular method later
return theMethods ;
public void RunMethod(Method[] SomeMethod, int methodcount)
try
SomeMethod[methodcount].invoke( object,null );
catch (Exception e)
e.printStackTrace();
// end class loader
//main calling program
import java.awt.*;
import java.awt.event.*;
import javax.swing .*;
import java.lang.reflect.*;
public class JFMenu extends JFrame
public static JMenu pluginMenu;
public static JMenuBar bar;
public static final Test2 w = new Test2();
public static Method[] setmethod;
private static ClassLinkList startRef = null;
private static ClassLinkList linkRef3 = null;
private static ClassLinkList startRef2 = null;
private String ClassName,ShortCut;
private int MethodNumber;
private JMenuItem PluginItem;
JFMenu()
super (" JFluro ");
JMenu fileMenu = new JMenu("File");
fileMenu.setMnemonic('F');
JMenuItem exitItem = new JMenuItem("Exit");
exitItem.setMnemonic('X');
fileMenu.add(exitItem);
exitItem.addActionListener
new ActionListener()
public void actionPerformed(ActionEvent event )
System.exit(0);
JMenu pluginMenu = new JMenu("Plugins");
pluginMenu.setMnemonic('P');
startRef = new ClassLinkList ("Hello","Hello ",2,1926,"Painter");
addToList("Foo","Foo ",0,1930,"Author");
while (startRef.linkRef5 != null)
//pluginMenu.addSeparator();
ClassName = startRef.linkRef5.className;
ShortCut = startRef.linkRef5.shortcutName;
MethodNumber = startRef.linkRef5.methodNumber;
AddMenuItem(pluginMenu,ShortCut,ClassName,MethodNumber);
startRef.linkRef5 = startRef.linkRef5.next;
// create menu bar and add JFMenu window to it
JMenuBar bar = new JMenuBar();
setJMenuBar(bar);
bar.add(fileMenu);
bar.add(pluginMenu);
//attributes for JFMenu frame
setSize(500,200);
setVisible(true);
}// end JFMenu constructor
public void AddMenuItem(JMenu MainMenu, String shortcut,String className, final int methodCount )
if (MainMenu==null)
return;
//JMenuItem item;
JMenuItem item = new JMenuItem(shortcut);
MainMenu.add(item);
setmethod = w.startClass(className);
item.addActionListener
new ActionListener()
public void actionPerformed(ActionEvent event )
w.RunMethod(setmethod,methodCount);
//item.addActionListener(ij);
public JMenuItem AddMenuItem2(JMenu MainMenu, String shortcut)
//if (MainMenu==null)
// return Main;
//JMenuItem item;
JMenuItem item = new JMenuItem(shortcut);
MainMenu.add(item);
//setmethod = w.startClass(className);
//item.addActionListener(this);
new ActionListener()
public void actionPerformed(ActionEvent event )
w.RunMethod(setmethod,methodCount);
//item.addActionListener(ij);
return item;
public void ReloadMenu(JMenuBar Bar, JMenu PluginMenu)
if (Bar==null)
return;
// setJMenuBar(Bar);
Bar.add(PluginMenu);
//item.addActionListener(ij);
public static void main (String args[])
JFMenu menapp = new JFMenu();
public static void addToList(String clname, String shcutname, int metnumber, int year2,
String description) {
// Create instance of class ClassLinkList
ClassLinkList newRef = new ClassLinkList(clname,shcutname,metnumber,year2,
description);
// Add to linked list;
startRef = startRef.addRecordToLinkedList(newRef);
// end main calling program
class Hello extends Thread
public int getNum()
System.out.println("I can be ");
return 5;
public void rayshowName()
System.out.println("anything i want ");
public void rayshowName3()
System.out.println("to be ");
class Foo extends Thread
public int getNum()
System.out.println("IMHOFF");
return 5;
public void rayshowName()
System.out.println("raYMOND");
// FAMOUS PERSONS LINKED LIST EXAMPLE
// Frans Coenen
// Saturday 15 January 2000
// Depaertment of Computer Science, University of Liverpool
class ClassLinkList {
/* FIELDS */
public String className;
public String shortcutName;
public int methodNumber;
public int yearOfDeath;
public String occupation;
public ClassLinkList next = null;
public ClassLinkList linkRef5 = this;
public ClassLinkList startRef = null;
/* CONSTRUCTORS */
/* FamousPerson constructor */
public ClassLinkList(String classname, String shortcutname, int methodnumber, int year2,
String description) {
className = classname;
shortcutName = shortcutname;
methodNumber = methodnumber;
yearOfDeath = year2;
occupation = description;
next = null;
/* METHODS */
/* Output famous person linked list */
public void outputClassLinkedList()
//public ClassLinkList outputClassLinkedList() {
ClassLinkList linkRef = this;
// Loop through linked list till end outputting each record in turn
while (linkRef != null)
//System.out.println(linkRef5);
System.out.println(linkRef.className + ", " + linkRef.shortcutName +
" (" + linkRef.methodNumber + "-" + linkRef.methodNumber +
"): " + linkRef.occupation);
linkRef = linkRef.next;
//return linkRef;
//public String ShowCasname()
//return String ;
/* Add a new record to the linked list */
public ClassLinkList addRecordToLinkedList(ClassLinkList newRef) {
ClassLinkList tempRef, linkRef;
// Test if new person is to be added to start of list if so return
if (newRef.testRecord(this) ) {
newRef.next = this;
return(newRef);
// Loop through remainder of linked list
tempRef = this;
linkRef = this.next;
while (linkRef != null) {
if (newRef.testRecord(linkRef)) {
tempRef.next = newRef;
newRef.next = linkRef;
return(this);
tempRef = linkRef;
linkRef = linkRef.next;
// Add to end
tempRef.next = newRef;
return(this);
/* Delete a record from the linked list given the first and last name. Four
posibilities:
1) Record to be deleted is at front of list
2) Record to be deleted is at end of list
3) Record to be deleted is in middle of list
4) Record not found. */
public ClassLinkList deleteRecord(String lName, String fName) {
ClassLinkList tempRef, linkRef;
// Record at start of list
if ((this.className == lName) & (this.shortcutName == fName))
return(this.next);
// Loop through linked list to discover if record is in middle of list.
tempRef = this;
linkRef = this.next;
while (linkRef != null) {
if ((linkRef.className == lName) & (linkRef.shortcutName == fName)) {
tempRef.next = linkRef.next;
return(this);
tempRef = linkRef;
linkRef = linkRef.next;
// Record at end of list, or not found
if ((linkRef.className == lName) & (linkRef.shortcutName == fName))
linkRef = null;
else System.out.println("Record: " + lName + " " + fName + " not found!");
return(this);
/* TEST METHODS */
/* Test whether new record comes before existing record or not. If so return
true, false otherwise. */
private boolean testRecord(ClassLinkList existingRef) {
int testResult = className.compareTo(existingRef.className);
if (testResult < 0) return(true);
else {
if ((testResult == 0) & (shortcutName.compareTo(existingRef.shortcutName) < 0 ))
return(true);
// Return false
return(false);
public void addToList(String clname, String shcutname, int metnumber, int year2,
String description)
// Create instance of class Famous Person
ClassLinkList newRef = new ClassLinkList(clname,shcutname,metnumber,year2,
description);
// Add to linked list;
startRef = startRef.addRecordToLinkedList(newRef);I have a similar problem. I am writing a program to read the class names from database and instantiate several classes which extends from ServiceThread (an abstract class extending from Thread).
rs = pStmt.executeQuery();
while(rs.next()) {
String threadclassname = rs.getString("classname").trim();
try{
ServiceThread threadinstance = (ServiceThread)Class.forName(threadclassname).newInstance();
}catch ...
So far, only the first class is ever instantiated and runs fine. But subsequent classes do not even get pass the "... ... Class.forName(...).newInstance();" line.
Funny thing is that there are also no exceptions. The JVM just seem to hang there. -
Failed loading disp class "HSIService". Exception java.lang.ClassCastExcep
<Failed loading disp class "HSIService". Exception java.lang.ClassCastExcep
Posted: 12 Aug 2004 13:36 PM Reply
I am receiving the following error in most all of the logs when trying to run/test this web service. The service worked fine a day ago, then this happened. I finally rebuilt it entirely in workshop, it ran a couple of times between changes and then started producing this error again. The workshop test browser either states "DispMessage is null" on the test form or if the form appears then it says "get" is not supported for the operation .... and maybe other weird stuff.
Can you give me an idea of where to specifically look for the problem?? Complete error message is below:
####<Aug 12, 2004 3:40:16 PM EDT> <Error> <WLW> <KLRAY8Z> <cgServer>
<ExecuteThread: '14' for queue: 'weblogic.kernel.Default'> <<anonymous>> <>
<Failed loading disp class "HSIService". Exception java.lang.ClassCastException at
com.bea.wlw.runtime.core.dispatcher.TypeUtils.validate(TypeUtils.java:1130)
at com.bea.wlw.runtime.jws.dispatcher.JwsDispClass.<init>(JwsDispClass.java:398)
at com.bea.wlw.runtime.jws.dispatcher.JwsDispFile.createPrimaryDispClass(JwsDispFile.java:52)
at com.bea.wlw.runtime.core.dispatcher.DispFile.<init>(DispFile.java:162)
at com.bea.wlw.runtime.jws.dispatcher.JwsDispFile.<init>(JwsDispFile.java:44)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:274)
at com.bea.wlw.runtime.core.dispatcher.DispUnit.loadDispFile(DispUnit.java:219)
at com.bea.wlw.runtime.core.dispatcher.DispUnit.<init>(DispUnit.java:153)
at com.bea.wlw.runtime.core.dispatcher.DispCache.ensureDispUnit(DispCache.java:553)
at com.bea.wlw.runtime.core.dispatcher.HttpServerHelper.getDispUnit(HttpServerHelper.java:491)
at com.bea.wlw.runtime.core.dispatcher.HttpServerHelper.executeGetRequest(HttpServerHelper.java:531)
at com.bea.wlw.runtime.core.dispatcher.HttpServer.doGet(HttpServer.java:81)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at weblogic.servlet.internal.ServletStubImpl$ServletInvocationAction.run(ServletStubImpl.java:971)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:402)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:305)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:6354)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:317)
at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:118)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:3635)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:2585)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:197)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:170)
>
--------------------------------------------------------FYI - solved this problem. The problem was that I had set a callback handler as an operation like so:
* @common:operation
* @common:message-buffer enable="true"
* @jws:conversation phase="finish"
public void mycontrol_mycallbackhandler()
Apparently callback handler's can not be operations. -
Error on Desktop: iTunes unable to load data class information from sync services.
Error on Desktop; iTunes unable to load data class information from sync services.
Hi there Randall112,
You may find the troubleshooting steps in the article below helpful.
iTunes for Windows: "Unable to load data class" or "Unable to load provider data" sync services alert
http://support.apple.com/kb/ts2690
-Griff W. -
iTunes was unable to load data class information from Sync Services. Reconnect or try again later. This is the message when I try to connect my iphone 4 to my computer. If anyone could help me with this, I would appreciate it.
iOS: Device not recognized in iTunes for Windows
http://support.apple.com/kb/TS1538
iOS: Device not recognized in iTunes for Mac OS X
http://support.apple.com/kb/ts1591 -
I keep getting this error message: ITunes was unable to load data class information from Synch Services. Reconnect or try again later. What does that mean? Can I fix it? or do I have to wait for the next update?
See TS2690: iTunes for Windows: "Unable to load data class" or "Unable to load provider data" sync services alert.
tt2 -
Was unable to load data class info from sync services. try again later.
Since installing the latest version of itunes (11.1.5.5) whenever I have either mine or my wife's iphones (4 and 5c, both with the latest 7.1.1) turned on and I start iTunes, I receive the error message saying that itunes was unable to load data class info from sync services. try again later.
If I leave the phones turned off and open iTunes, I am able to sync my old ipod so it appears to be an issue with the software on the phones?
I'm just not sure where to start. I've made sure that itunes has the latest version and no more updates are available.
Thanks in advance,
jamey8420this is on a windows 7 machine, btw.
-
ITunes was unable to load data class information from Sync Services. Reconnect or try again later.
Ever since I upgraded to iTunes 10.4 I've been getting this dreaded message on many occasions when I try to sync my iPhone 4 or iPad 2 with my Win 7 64 bit machine. "iTunes was unable to load data class information from Sync Services. Reconnect or try again later." What happens is that local content (music, videos etc) will sync properly to my iPhone, but other content (such as Outlook information, MobileMe stuff, etc) will not.
I have uninstalled and completely purged all Apple data from my PC (including hidden files and folders under Common Files and in the Registry) and reinstalled iTunes. Yet after one or two syncs, the same problem resurfaces. The other weird part is that the Sync Services crap-out message will happen after I do a successful sync, leave the iPhone connected to the PC, and don't even touch the computer for several hours.
I've actually developed a very tedious work around that seems to restore syncing if for a short time.
- Undock/unconnect all Apple devices from the PC.
- Close iTunes, MobileMe control panel, and Safari (if you have it).
- Start Task Manager (Ctrl + Alt + Del) and shut down iTunesHelper.exe and SyncServer.exe
- Open up a Windows Explorer window (like My Computer) and under Tools, Folder Options, View, toggle on Show Hidden Files and toggle off Hide Protected Operating System FIles
- In WIndows Explorer, navigate to "C:\Users\<your name>\App Data\Roaming\Apple Computer". Rename the folder Sync Services to something else, like Sync Services_Old.
- In WIndows Explorere, navigate to "C:\Program Files (x86)\Common Files\Apple\Mobile Device Support" and double-click on AppleSyncNotifier.exe.
- Go back to your Folder Options and turn off SHow Hidden Files and toggle on Hide Protected Operationg System Files
Now you can start up iTunes again and connect your device. It should sync properly again (at least, until it doesn't once more).
Does anyone at Apple have any idea about this error or a solution?I actually spent a fair amount of time on the phone with a senior Apple tech last week. He directed me to this topic:
http://support.apple.com/kb/HT1923?viewlocale=en_US
It's important that you go through the steps EXACTLY as described here and in the proper order. Also make sure MobileMe control panel is uninstalled (if you have it).
Interestingly, when I went through this procedure and then reinstalled iTunes 10.4 64-bit (didn't do MobileMe or Safari at this stage, but QT is automatically installed) everything worked perfectly. The aforementioned error messages disappeared and all is working flawlessly, as it should.
I hope my expereince will help! Give it a try.
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