背景

springmvc應用最近從windows遷移到ubuntu18.04,前端驗證碼無法載入，後來看控制檯報以下錯誤

2020-08-06 15:49:49,983 ERROR [500.jsp] - Could not initialize class javax.imageio.ImageIO
java.lang.NoClassDefFoundError: Could not initialize class javax.imageio.ImageIO
        at com.google.code.kaptcha.servlet.KaptchaServlet.init(KaptchaServlet.java:
 
50)
        at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1241)
        at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1154)
        at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:827)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:
 
135)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:
 
79)
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:534)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1081)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:658)
        at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:222)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1566)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1523)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.lang.Thread.run(Thread.java:748)

前端現象：

這個出錯原因比較簡單，因為linux是非圖形介面啟動，沒載入相關圖形函式庫，繪製驗證碼的過程中報錯了，最早從事java工作的時候遇到過，那個部落格（百度空間）無效了。

再次記錄一下。

解決方法

#開啟檔案，新增JVM引數
vim apache-tomcat-8.0.11/bin/catalina.sh
#新增
JAVA_OPTS="-Djava.awt.headless=true -Dawt.toolkit=sun.awt.HToolkit"

如圖

重啟tomcat後如下