weblogic环境，应用上传图片报Could not initialize class sun.awt.X11.XToolkit

问题描述

遇到的问题是在weblogic环境，应用在上传图片的时候报Could not initialize class sun.awt.X11.XToolkit 错误。

具体错误如下

17:57:02 [AWT-EventQueue-2] DEBUG - Leaving class nc.ui.hi.psndoc.action.SavePsndocAction.actionPerformed Exception in thread "AWT-EventQueue-2" java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11.XToolkitat java.lang.Class.forName0(Native Method)at java.lang.Class.forName(Class.java:169)at java.awt.Toolkit$2.run(Toolkit.java:834)at java.security.AccessController.doPrivileged(Native Method)at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:826)at javax.swing.ImageIcon.<init>(ImageIcon.java:236)at nc.pub.tools.VOUtils.transPreviewPhoto(VOUtils.java:212)at nc.impl.hi.psndoc.PsndocValidator.setPreviewPhoto(PsndocValidator.java:1338)at nc.impl.hi.psndoc.PsndocValidator.adjustPsndoc(PsndocValidator.java:1320)at nc.impl.hi.psndoc.PsndocValidator.validate(PsndocValidator.java:819)at nc.impl.hi.psndoc.PsndocServiceImpl.savePsndoc(PsndocServiceImpl.java:1616)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)at java.lang.reflect.Method.invoke(Method.java:597)at nc.bs.framework.aop.rt.MethodProceedingJoinpoint$3.invoke(MethodProceedingJoinpoint.java:74)at nc.bs.framework.aop.rt.MethodProceedingJoinpoint.proceed(MethodProceedingJoinpoint.java:184)at nc.bs.framework.server.SecurityAspect.aroundMethod1(SecurityAspect.java:45)at sun.reflect.GeneratedMethodAccessor156.invoke(Unknown Source)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)at java.lang.reflect.Method.invoke(Method.java:597)at nc.bs.framework.aop.rt.AdviceHolder.invoke(AdviceHolder.java:182)at nc.bs.framework.aop.rt.MethodProceedingJoinpoint.proceed(MethodProceedingJoinpoint.java:129)at nc.bs.framework.aop.rt.MethodProceedingJoinpoint.proceed(MethodProceedingJoinpoint.java:135)at nc.bs.aop.log.BusilogAspect.aroundMethod(BusilogAspect.java:75)at sun.reflect.GeneratedMethodAccessor1769.invoke(Unknown Source)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)at java.lang.reflect.Method.invoke(Method.java:597)at nc.bs.framework.aop.rt.AdviceHolder.invoke(AdviceHolder.java:182)at nc.bs.framework.aop.rt.MethodProceedingJoinpoint.proceed(MethodProceedingJoinpoint.java:129)at nc.bs.framework.aop.rt.MethodProceedingJoinpoint.proceed(MethodProceedingJoinpoint.java:135)at nc.bs.framework.aop.rt.AspectedProxy.invoke(AspectedProxy.java:59)at $Proxy519.savePsndoc(Unknown Source)at nc.itf.hr.hi.HRhiEJBEjbBean.savePsndoc(HRhiEJBEjbBean.java:2812)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)at java.lang.reflect.Method.invoke(Method.java:597)at com.bea.core.repackaged.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:310)at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182)at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:131)at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:119)at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)at com.bea.core.repackaged.springframework.jee.spi.MethodInvocationVisitorImpl.visit(MethodInvocationVisitorImpl.java:37)at weblogic.ejb.container.injection.EnvironmentInterceptorCallbackImpl.callback(EnvironmentInterceptorCallbackImpl.java:54)at com.bea.core.repackaged.springframework.jee.spi.EnvironmentInterceptor.invoke(EnvironmentInterceptor.java:50)at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)at com.bea.core.repackaged.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:89)at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:131)at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:119)at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)at com.bea.core.repackaged.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)at $Proxy514.savePsndoc(Unknown Source)

解决办法

在启动java服务器的时候，在启动参数中加入以下参数

-Djava.awt.headless=true

headless问题探讨

关于java服务器的headless模式，oracle官网的说明为：

http://www.oracle.com/technetwork/articles/javase/headless-136834.html

其中很多概念我也不是很理解

大致意思就是，在java服务器端，有许多图形界面的处理函数，需要调用显示器，鼠标键盘这些设备，但有些处理函数则不需要，如果设置了这个headless之后，图形界面的处理和渲染是分开的，用于生成图片的工作放在服务器端进行，生成后将编码传到客户端，再在客户端进行渲染和显示。

这主要用了服务器端的高计算能力，然后把需要调用显示器相关的工作传到客户端去执行。

以上的错误本身是要初始化X11服务器，然后用X11的工具箱去做图形生成计算这等事，但是X11初始化失败，应该是X11的安装环境有问题，于是可以设置java参数

-Djava.awt.headless=true

这个参数，使用java自带的这个服务器工具箱。

以上是我的理解，对错有待验证。