weblogic環境，應用上傳圖片報Could not initialize class sun.awt.X11.XToolkit

問題描寫敘述

遇到的問題是在weblogic環境，應用在上傳圖片的時候報Could not initialize class sun.awt.X11.XToolkit 錯誤。

詳細錯誤例如以下

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.XToolkit
	at 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)

解決的方法

在啟動javaserver的時候。在啟動參數中增加下面參數

-Djava.awt.headless=true

headless問題探討

關於javaserver的headless模式。oracle官網的說明為：

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

當中非常多概念我也不是非常理解

大致意思就是，在javaserver端，有很多圖形界面的處理函數。須要調用顯示器，鼠標鍵盤這些設備，但有些處理函數則不須要。假設設置了這個headless之后。圖形界面的處理和渲染是分開的，用於生成圖片的工作放在server端進行，生成后將編碼傳到client，再在client進行渲染和顯示。

這主要用了server端的高計算能力。然后把須要調用顯示器相關的工作傳到client去運行。

以上的錯誤本身是要初始化X11server。然后用X11的工具箱去做圖形生成計算這等事。可是X11初始化失敗。應該是X11的安裝環境有問題，於是能夠設置java參數

-Djava.awt.headless=true

這個參數。使用java自帶的這個server工具箱。

以上是我的理解，對錯有待驗證。