linux 下servlet画图不显示问题

﹏ヽ暗。殇╰゛Y 2022-04-15 07:39 209阅读 0赞

画图代码在windowxp和有些linux服务器上会没有问题，今天在别的机器上发现运行后卡死在Graphics2D g = buffImg.createGraphics();

由于使用了框架，但是没有看到报错。在网上找了解决方法，同时发现网上有些写法差不多但是可以捕获异常。

解决方法：

在tomcat部署目录下的bin目录里面的catalina.sh启动文件加入下面的红色字体部分就可以了（注意该文件的编码为unix）。

elif \[ "$1" = "start" \] ;then  
shift  
touch “$CATALINA\_BASE”/logs/catalina.out  
if \[ "$1" = "-security" \] ; then  
echo “Using Security Manager”  
shift  
“$\_RUNJAVA” $JAVA\_OPTS $CATALINA\_OPTS  
\-Djava.endorsed.dirs=”$JAVA\_ENDORSED\_DIRS” -classpath “$CLASSPATH”  
\-Djava.security.manager  
\-Djava.security.policy==”$CATALINA\_BASE”/conf/catalina.policy  
\-Dcatalina.base=”$CATALINA\_BASE”  
\-Dcatalina.home=”$CATALINA\_HOME”  
\-Djava.io.tmpdir=”$CATALINA\_TMPDIR”  
**-Djava.awt.headless=true**  
org.apache.catalina.startup.Bootstrap “$@” start  
>> “$CATALINA\_BASE”/logs/catalina.out 2>&1 &  
if \[ ! -z "$CATALINA\_PID" \]; then  
echo $! > $CATALINA\_PID  
fi  
else  
“$\_RUNJAVA” $JAVA\_OPTS $CATALINA\_OPTS  
\-Djava.endorsed.dirs=”$JAVA\_ENDORSED\_DIRS” -classpath “$CLASSPATH”  
\-Dcatalina.base=”$CATALINA\_BASE”  
\-Dcatalina.home=”$CATALINA\_HOME”  
\-Djava.io.tmpdir=”$CATALINA\_TMPDIR”  
**-Djava.awt.headless=true**  
org.apache.catalina.startup.Bootstrap “$@” start  
>> “$CATALINA\_BASE”/logs/catalina.out 2>&1 &  
if \[ ! -z "$CATALINA\_PID" \]; then  
echo $! > $CATALINA\_PID  
fi  
fi  
编辑完成后，重新启动tomcat，然后再运行画图程序，That’s OK!  
经过测试，在weblogic中也可以采用类似的方法，然后画图的时候也不需要Xserver。具体的做法就是在weblogic的启动脚本startWebLogic.sh的最后部分中加入“-Djava.awt.headless=true”。如下橙色字体所示（只摘抄部分）：  
….  
$\{JAVA\_HOME\}/bin/java $\{JAVA\_VM\} $\{MEM\_ARGS\} $\{JAVA\_OPTIONS\} -Dweblogic.Name=$\{SERVER\_NAME\} -Dweblogic.ProductionModeEnabled=$\{PRODUCTION\_MODE\} -Djava.security.policy=”$\{WL\_HOME\}/server/lib/weblogic.policy”**-Djava.awt.headless=true**weblogic.Server

异常如下：

一、

1.  500ServletException
2.  java.lang.NoClassDefFoundError
3.  atjava.lang.Class.forName0(NativeMethod)
4.  atjava.lang.Class.forName(Class.java:120)
5.  atjava.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:58)
6.  atjava.awt.image.BufferedImage.createGraphics(BufferedImage.java:1011)
7.  atjava.awt.image.BufferedImage.getGraphics(BufferedImage.java:1001)
8.  atimage.mvc.vc.VC.Paint(VC.java:66)
9.  atimage.run.Servlet.doGet(Servlet.java:183)
10. atjavax.servlet.http.HttpServlet.service(HttpServlet.java:740)
11. atjavax.servlet.http.HttpServlet.service(HttpServlet.java:853)
12. atcom.caucho.server.http.FilterChainServlet.doFilter(FilterChainServlet.java:96)
13. atcom.caucho.server.http.Invocation.service(Invocation.java:315)
14. atcom.caucho.server.http.CacheInvocation.service(CacheInvocation.java:135)
15. atcom.caucho.server.http.RunnerRequest.handleRequest(RunnerRequest.java:346)
16. atcom.caucho.server.http.RunnerRequest.handleConnection(RunnerRequest.java:274)
17. atcom.caucho.server.TcpConnection.run(TcpConnection.java:139)  
    
18. atjava.lang.Thread.run(Thread.java:484)

二、

\[ERROR\]2005-07-2121:16:28org.jboss.web.localhost.Engine-StandardWrapperValve\[jsp\]:Servlet.service()forservletjspthrewexception  
java.lang.InternalError:Can'tconnecttoX11windowserverusing':0.0'asthevalueoftheDISPLAYvariable.  
atsun.awt.X11GraphicsEnvironment.initDisplay(NativeMethod)  
atsun.awt.X11GraphicsEnvironment.<clinit>(X11GraphicsEnvironment.java:134)  
atjava.lang.Class.forName0(NativeMethod)  
atjava.lang.Class.forName(Class.java:141)  
atjava.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:62)  
atjava.awt.image.BufferedImage.createGraphics(BufferedImage.java:1041)  
atjava.awt.image.BufferedImage.getGraphics(BufferedImage.java:1031)  
atcom.sww.helper.Image.creatImage(Image.java:30)

三、

SEVERE: Servlet.service() for servlet validatecode threw exception  
java.lang.InternalError: Can't connect to X11 window server using '192.168.1.1:1.0' as the value of the DISPLAY variable.  
at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)  
at sun.awt.X11GraphicsEnvironment.access$100(X11GraphicsEnvironment.java:52)  
at sun.awt.X11GraphicsEnvironment$1.run(X11GraphicsEnvironment.java:155)  
at java.security.AccessController.doPrivileged(Native Method)  
at sun.awt.X11GraphicsEnvironment.<clinit>(X11GraphicsEnvironment.java:131)  
at java.lang.Class.forName0(Native Method)  
at java.lang.Class.forName(Class.java:169)  
at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:68)  
at java.awt.image.BufferedImage.createGraphics(BufferedImage.java:1135)  
at com.newyulong.iptv.webapp.servlet.ValidateCodeServlet.service(ValidateCodeServlet.java:53)  
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)  
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)  
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)  
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)  
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)  
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)  
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)  
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)  
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)  
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)  
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)  
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)  
at java.lang.Thread.run(Thread.java:619)  
Sep 8, 2013 6:54:02 PM org.apache.catalina.core.StandardWrapperValve invoke  
SEVERE: Servlet.service() for servlet validatecode threw exception  
java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11GraphicsEnvironment  
at java.lang.Class.forName0(Native Method)  
at java.lang.Class.forName(Class.java:169)  
at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:68)  
at java.awt.image.BufferedImage.createGraphics(BufferedImage.java:1135)  
at com.newyulong.iptv.webapp.servlet.ValidateCodeServlet.service(ValidateCodeServlet.java:53)  
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)  
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)  
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)  
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)  
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)  
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)  
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)  
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)  
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)  
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)  
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)  
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)  
at java.lang.Thread.run(Thread.java:619)  
Sep 8, 2013 6:54:02 PM org.apache.catalina.core.StandardWrapperValve invoke  
SEVERE: Servlet.service() for servlet validatecode threw exception  
java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11GraphicsEnvironment  
at java.lang.Class.forName0(Native Method)  
at java.lang.Class.forName(Class.java:169)  
at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:68)  
at java.awt.image.BufferedImage.createGraphics(BufferedImage.java:1135)  
at com.newyulong.iptv.webapp.servlet.ValidateCodeServlet.service(ValidateCodeServlet.java:53)  
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)  
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)  
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)  
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)  
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)  
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)  
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)  
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)  
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)  
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)  
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)  
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)  
at java.lang.Thread.run(Thread.java:619)

四、

servlet画图类部分代码：

public class ValidateCodeServlet extends HttpServlet \{

/\*\*  
\*  
\*/  
private static final long serialVersionUID = 1L;  
  
int w = 60;  
int h = 20;  
int fh = 10;  
int cy = 0;  
int x = 1;  
int cc = 4;  
  
char\[\] cs = \{ 'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q'  
,'R','S','T','U','V','W','X','Y','Z', '2', '3', '4', '5', '6',  
'7', '8', '9'  
\};  
  
protected void service(HttpServletRequest req, HttpServletResponse resp)  
throws ServletException, java.io.IOException \{  
  
x = w / (cc + 1);  
fh = h - 2;  
cy = h - 4;  
  
// image buffer  
BufferedImage buffImg = new BufferedImage(w, h,  
BufferedImage.TYPE\_INT\_RGB);  
Graphics2D g = buffImg.createGraphics();  
  
Random random = new Random();  
  
// fill image with white color  
g.setColor(Color.WHITE);  
g.fillRect(0, 0, w, h);  
  
// create font  
Font font = new Font("Fixedsys", Font.PLAIN | Font.BOLD, fh);  
// set font  
g.setFont(font);  
  
g.setColor(Color.blue);  
g.drawRect(0, 0, w - 1, h - 1);

..................................................

\}  
\}