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javagwtgoogle-plugin-eclipse

"Development mode is loading..." and "Waiting for launch URLs" in GWT

I am a beginner in GWT and trying to run a sample HelloWorld program from http://www.vogella.com/tutorials/GWT/article.html. I installed the GWT plugin for Eclipse Kepler 4.3 and downloaded GWT SDK 2.3. While configuring SDK in eclipse, i was getting error that "gwt-codeserver.jar is missing" so i downloaded "gwt-codserver-2.5" jar and copied it to SDK folder and it fixed missing jar issue.

Then i run my application by right-click on the project and selected Run As -> "Web application". Now, i am not getting the url in the Development mode tab instead it shows "Development mode is loading...." and "Waiting for launch URLs" message continuously and nothing happens after that. In console i am getting below message. Please help to fix this issue.

    Unknown Argument: -superDevMode
    DevMode [-[no]startServer] [-port port-number | "auto"] [-whitelist whitelist-string] [-blacklist blacklist-string] [-logdir directory] [-logLevel level] [-gen dir] [-bindAddress host-name-or-address] [-codeServerPort port-number | "auto"] [-server servletContainerLauncher[:args]] [-startupUrl url] [-war dir] [-deploy dir] [-extra dir] [-workDir dir] [-sourceLevel [auto, 1.6, 1.7]] module[s] 

    where 
      -[no]startServer  Starts a servlet container serving the directory specified by the -war flag. (defaults to ON)
      -port             Specifies the TCP port for the embedded web server (defaults to 8888)
      -whitelist        Allows the user to browse URLs that match the specified regexes (comma or space separated)
      -blacklist        Prevents the user browsing URLs that match the specified regexes (comma or space separated)
      -logdir           Logs to a file in the given directory, as well as graphically
      -logLevel         The level of logging detail: ERROR, WARN, INFO, TRACE, DEBUG, SPAM, or ALL
      -gen              Debugging: causes normally-transient generated types to be saved in the specified directory
      -bindAddress      Specifies the bind address for the code server and web server (defaults to 127.0.0.1)
      -codeServerPort   Specifies the TCP port for the code server (defaults to 9997)
      -server           Specify a different embedded web server to run (must implement ServletContainerLauncher)
      -startupUrl       Automatically launches the specified URL
      -war              The directory into which deployable output files will be written (defaults to 'war')
      -deploy           The directory into which deployable but not servable output files will be written (defaults to 'WEB-INF/deploy' under the -war directory/jar, and may be the same as the -extra directory/jar)
      -extra            The directory into which extra files, not intended for deployment, will be written
      -workDir          The compiler's working directory for internal use (must be writeable; defaults to a system temp dir)
      -sourceLevel      Specifies Java source level (defaults to auto:1.7)
    and 
      module[s]         Specifies the name(s) of the module(s) to host
Solution

  • Both errors (missing gwt-codeserver, and unknown argument) hint that the Google Plugin for Eclipse didn't properly detect the version of the GWT SDK you're using.

    GWT 2.3 is now really old, so I'd suggest trying with GWT 2.7. As you're beginning with GWT, it's also better to start right with SuperDevMode than lose days trying to make DevMode work with recent browsers. Note: that means you'll debug from within the browser, not your IDE (unless you install the SDBG plugin from https://sdbg.github.io)