Java Can't connect to X11 window server using 'localhost:10.0' as the value of the DISPLAY variable

Question

I have a script using java to connect to display X11 in the port 10.0 at localhost

but i get always this error

java.lang.InternalError: Can't connect to X11 window server using 'localhost:10.0' as the value of the DISPLAY variable.
    at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)
    at sun.awt.X11GraphicsEnvironment.access$200(X11GraphicsEnvironment.java:62)
    at sun.awt.X11GraphicsEnvironment$1.run(X11GraphicsEnvironment.java:178)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.awt.X11GraphicsEnvironment.<clinit>(X11GraphicsEnvironment.java:142)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:186)
    at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:82)
    at sun.awt.X11.XToolkit.<clinit>(XToolkit.java:112)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:186)
    at java.awt.Toolkit$2.run(Toolkit.java:849)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:841)
    at ij.io.Opener.openJpegOrGif(Opener.java:367)
    at ij.io.Opener.openImage(Opener.java:220)
    at ij.io.Opener.openImage(Opener.java:249)
    at ij.io.Opener.open(Opener.java:116)
    at ij.IJ.open(IJ.java:1112)
    at ij.macro.Functions.open(Functions.java:2006)
    at ij.macro.Functions.doFunction(Functions.java:129)
    at ij.macro.Interpreter.doStatement(Interpreter.java:205)
    at ij.macro.Interpreter.doBlock(Interpreter.java:515)
    at ij.macro.Interpreter.runUserFunction(Interpreter.java:278)
    at ij.macro.Interpreter.getFactor(Interpreter.java:1200)
    at ij.macro.Interpreter.getTerm(Interpreter.java:1162)
    at ij.macro.Interpreter.getExpression(Interpreter.java:1145)
    at ij.macro.Interpreter.getBooleanExpression(Interpreter.java:881)
    at ij.macro.Interpreter.getLogicalExpression(Interpreter.java:857)
    at ij.macro.Interpreter.getBoolean(Interpreter.java:850)
    at ij.macro.Interpreter.doIf(Interpreter.java:829)
    at ij.macro.Interpreter.doStatement(Interpreter.java:217)
    at ij.macro.Interpreter.doBlock(Interpreter.java:515)
    at ij.macro.Interpreter.doStatement(Interpreter.java:241)
    at ij.macro.Interpreter.doIf(Interpreter.java:831)
    at ij.macro.Interpreter.doStatement(Interpreter.java:217)
    at ij.macro.Interpreter.doStatements(Interpreter.java:195)
    at ij.macro.Interpreter.run(Interpreter.java:99)
    at ij.macro.Interpreter.run(Interpreter.java:65)
    at ij.macro.Interpreter.run(Interpreter.java:75)
    at ij.plugin.Macro_Runner.runMacro(Macro_Runner.java:127)
    at ij.plugin.Macro_Runner.runMacroFile(Macro_Runner.java:112)
    at ij.IJ.runMacroFile(IJ.java:103)
    at ij.ImageJ.main(ImageJ.java:517)

I have tried everything to solve this problem like :

export DISPLAY=:10.0
export DISPLAY=localhost:10.0

I tried also the port 0.0 but i get always the same error

after trying xhost

xhost +local:all
xhost:  unable to open display ""
xhost:  unable to open display ":10.0"

how can i fix this i thought that the X Server is not runing so i tried startx its says its runing at that port

my system is Ubuntu server edition 10.04

Answer 1

You need to specify the -Djava.awt.headless=true parameter at startup time.