我试图在浏览器中运行applet时遇到问题。我得到一个NullPointerException,我无法确定它出错了。开放式移位Java Applet
这里是堆栈跟踪:
Java Plug-in 10.60.2.19
Using JRE version 1.7.0_60-b19 Java HotSpot(TM) Client VM
User home directory = C:\Users\Alexandru
----------------------------------------------------
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
q: hide console
r: reload policy configuration
s: dump system and deployment properties
t: dump thread list
v: dump thread stack
x: clear classloader cache
0-5: set trace level to <n>
----------------------------------------------------
java.lang.NullPointerException
at sun.awt.SunToolkit.getSystemEventQueueImplPP(Unknown Source)
at sun.awt.SunToolkit.getSystemEventQueueImplPP(Unknown Source)
at sun.awt.SunToolkit.getSystemEventQueueImpl(Unknown Source)
at java.awt.Toolkit.getEventQueue(Unknown Source)
at java.awt.EventQueue.invokeLater(Unknown Source)
at sun.awt.windows.WToolkit.windowsSettingChange(Unknown Source)
at sun.awt.windows.WToolkit.eventLoop(Native Method)
at sun.awt.windows.WToolkit.run(Unknown Source)
我得到这个后,我得到一个Quiz.class ClassNotFound的。
这里是我的代码:
<jsp:plugin type="applet" code="Quiz.class" codebase="../target/classes" width="500" height="280">
<jsp:fallback>
<p> Unable to load applet </p>
</jsp:fallback>
</jsp:plugin>
我试图运行OpenShift云服务的应用程序。我的服务器使用JBoss运行,它应该创建一个测验并将其显示在applet中。我已经创建了测验,并且可以通过jsp将其显示在浏览器中,但现在由于安全问题,现在我试图在applet中显示它。
这里是我的applet代码(这个小程序是仅用于测试,我应设法以显示它的测验后,我解决了这个问题):
package models;
import java.applet.Applet;
import java.awt.Graphics;
public class Quiz extends Applet{
/**
*
*/
private static final long serialVersionUID = 1L;
public void paint(Graphics g)
{
g.drawString("My applet",400,200);
}
}
我的项目是基于Maven的,我想这很重要。我尝试从我的applet中将编译后的类添加到jar中,并在运行时使用Maven插件将其添加到webapp文件夹中,使用此示例Maven - Copy Some Dependency JARs into warSourceDirectory但它没有帮助。我也试图直接使用这个插件编译类WebApp文件夹:
<pluginRepositories>
<pluginRepository>
<id>eap</id>
<url>http://maven.repository.redhat.com/techpreview/all</url>
<releases>
<enabled>true</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
与此配置文件:
<profile>
<id>copy</id>
<build>
<plugins>
<plugin>
<groupId>com.github.goldin</groupId>
<artifactId>copy-maven-plugin</artifactId>
<version>0.2.5</version>
<executions>
<execution>
<id>create-archive</id>
<phase>generate-resources</phase>
<goals>
<goal>copy</goal>
</goals>
<configuration>
<resources>
<resource>
<targetPath>${project.build.outputDirectory}/work/webapp/WEB-INF/classes/</targetPath>
<directory>${project.basedir}/src/main/webapp</directory>
</resource>
</resources>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</profile>
,但它也不能工作。还有其他建议吗?
代码库是一个HTTP路径,与Maven目录布局无关。 – chrylis