JApplet

olga
14 de Septiembre del 2009
Hola estoy haciendo un JApplet y al ejecutar el html me da este error y nose el porque. Si alguien me podria ayudar lo agradeceria mucho. El codigo html es:

<HTML>
<HEAD>
<TITLE> Applet de ejemplo </TITLE>
</HEAD>

<BODY>

<H1> Applet Java </H1>

<APPLET CODE = Datos_representar.class WIDTH = 300 HEIGHT = 300>
</APPLET>

</BODY>
</HTML>

y me sale lo siguiente:

cargar: clase “Datos_representar.class” no encontrada.
java.lang.ClassNotFoundException: “Datos_representar.class”
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.io.FileNotFoundException: C:Archivos de programaeclipse-SDK-3.0.2-win32programasRNAdatos_representar“Datos_representarclass”.class (El sistema no puede hallar la ruta especificada)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at sun.net.www.protocol.file.FileURLConnection.connect(Unknown Source)
at sun.net.www.protocol.file.FileURLConnection.getInputStream(Unknown Source)
at sun.applet.AppletClassLoader.getBytes(Unknown Source)
at sun.applet.AppletClassLoader.access$100(Unknown Source)
at sun.applet.AppletClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
... 10 more
Exception in thread "Thread-5" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletStatus(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "thread applet-“Datos_representar.class”" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NoClassDefFoundError: Datos_representar (wrong name: datos_representar/Datos_representar)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "Thread-13" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletStatus(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "thread applet-Datos_representar.class" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NoClassDefFoundError: Datos_representar (wrong name: datos_representar/Datos_representar)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "Thread-18" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletStatus(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "thread applet-Datos_representar.class" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
cargar: clase .Datos_representar.class no encontrada.
java.lang.ClassNotFoundException: ..Datos_representar.class
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.net.UnknownHostException: Datos_representar
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.net.NetworkClient.doConnect(Unknown Source)
at sun.net.NetworkClient.openServer(Unknown Source)
at sun.net.ftp.FtpClient.openServer(Unknown Source)
at sun.net.ftp.FtpClient.openServer(Unknown Source)
at sun.net.www.protocol.ftp.FtpURLConnection.connect(Unknown Source)
at sun.net.www.protocol.ftp.FtpURLConnection.getInputStream(Unknown Source)
at sun.applet.AppletClassLoader.getBytes(Unknown Source)
at sun.applet.AppletClassLoader.access$100(Unknown Source)
at sun.applet.AppletClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
... 10 more
Exception in thread "Thread-24" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletStatus(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "thread applet-.Datos_representar.class" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
cargar: clase datos_representar.Datos_representar.class no encontrada.
java.lang.ClassNotFoundException: datos_representar.Datos_representar.class
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.io.FileNotFoundException: C:Archivos de programaeclipse-SDK-3.0.2-win32programasRNAdatos_representardatos_representarDatos_representarclass.class (El sistema no puede hallar la ruta especificada)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at sun.net.www.protocol.file.FileURLConnection.connect(Unknown Source)
at sun.net.www.protocol.file.FileURLConnection.getInputStream(Unknown Source)
at sun.applet.AppletClassLoader.getBytes(Unknown Source)
at sun.applet.AppletClassLoader.access$100(Unknown Source)
at sun.applet.AppletClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
... 10 more
Exception in thread "Thread-28" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletStatus(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "thread applet-datos_representar.Datos_representar.class" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.security.AccessControlException: access denied (java.io.FilePermission C:Archivos de programaeclipse-SDK-3.0.2-win32programasProyectoSBaseDatos.txt read)
at java.security.AccessControlContext.checkPermission(Unknown Source)
at java.security.AccessController.checkPermission(Unknown Source)
at java.lang.SecurityManager.checkPermission(Unknown Source)
at java.lang.SecurityManager.checkRead(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at datos_representar.FicheroBD.leer_fichero(FicheroBD.java:90)
at datos_representar.BaseDatosPanel1.BDPanel1(BaseDatosPanel1.java:61)
at datos_representar.Datos_representar.IDatos_representar(Datos_representar.java:38)
at datos_representar.Datos_representar.init(Datos_representar.java:52)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread "thread applet-datos_representar.Datos_representar.class" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)


Muchas graciasssssss.

an?a
14 de Septiembre del 2009
Hola, creo que puede ser porque te falta poner el codebase, que es la carpeta donde tiene que buscar el archivo .class.

Es decir, tienes que tener el archivo .html, y en ese mismo directorio una carpeta donde esté Datos_representar.class

En mi caso tenía esto

<APPLET codebase=\"classes\" code=\"com/proyecto/regletas/Sistema.class\" width=1190 height=700></APPLET>

Espero sirva de ayuda a alguien.

Katrym
14 de Septiembre del 2009
A mi se passa algo muy parecido. Al ejecutar em AppletViewer puedo ejecutar todas las funciones de mi applet, pero en browser (OC4J Server) tengo los seguintes erros:

load: class Cliente.class not found.
java.lang.ClassNotFoundException: Cliente.class
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.io.IOException: open HTTP connection failed.
at sun.applet.AppletClassLoader.getBytes(Unknown Source)
at sun.applet.AppletClassLoader.access$100(Unknown Source)
at sun.applet.AppletClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
... 10 more
Exception in thread \"Thread-4\" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletStatus(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Exception in thread \"thread applet-Cliente.class\" java.lang.NullPointerException
at sun.plugin.util.GrayBoxPainter.showLoadingError(Unknown Source)
at sun.plugin.AppletViewer.showAppletException(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)


Gracias por todo.