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javagradleprogram-entry-point

run main method using gradle "run" task


I want to run my main method via gradle task

This is how I run via the cmd:

java -cp RTMonitor.jar com.bla.MainRunner first_arg

how should it be written in gradle?

run {
    args += ['java -cp RTMonitor.jar com.bla.MainRunner first_arg']
}

Update

I have tried

task myRun(type: JavaExec) {
    classpath configurations.main
    main = "com.bla.runners.StatsLogGenerator"
    args "arg1", "arg2"
}

and I got:

Error:(71, 0) Could not find property 'main' on configuration container.

the I have tried:
    task myRun(type: JavaExec) {
        classpath "configurations.main"
        main = "com.bla.runners.StatsLogGenerator"
        args "arg1", "arg2"
    }

and i got an error:

FAILURE: Build failed with an exception.
17:49:21.855 [ERROR] [org.gradle.BuildExceptionReporter] 
17:49:21.856 [ERROR] [org.gradle.BuildExceptionReporter] * What went wrong:
17:49:21.856 [ERROR] [org.gradle.BuildExceptionReporter] Execution failed for task ':myRun'.
17:49:21.856 [ERROR] [org.gradle.BuildExceptionReporter] > Process 'command '/Library/Java/JavaVirtualMachines/jdk1.8.0_25.jdk/Contents/Home/bin/java'' finished with non-zero exit value 1
17:49:21.864 [ERROR] [org.gradle.BuildExceptionReporter] 
17:49:21.865 [ERROR] [org.gradle.BuildExceptionReporter] * Exception is:
17:49:21.866 [ERROR] [org.gradle.BuildExceptionReporter] org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':myRun'.
17:49:21.867 [ERROR] [org.gradle.BuildExceptionReporter]    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:69)

17:49:21.882 [ERROR] [org.gradle.BuildExceptionReporter]    at org.gradle.process.internal.DefaultExecHandle$ExecResultImpl.assertNormalExitValue(DefaultExecHandle.java:361)
17:49:21.882 [ERROR] [org.gradle.BuildExceptionReporter]    at org.gradle.process.internal.DefaultJavaExecAction.execute(DefaultJavaExecAction.java:31)

but when I run via Intellij, every thig works OK


Solution

  • The easiest is probably to use application plugin. Add apply plugin: 'application' to your build.gradle and set mainClassName = com.bla.MainRunner . To add arguments to your main class modify the run task and edit the args property

    run {
      args += 'first_arg'
    }
    

    Classpath is taken automatically from main sourceSet, if you want different one, you can edit classpath property of the run task.

    If you need more customization, you can define your own task of type JavaExec like this

    task myRun(type: JavaExec) {
      classpath sourceSets.main.runtimeClasspath
      main = "com.bla.MainRunner"
      args "arg1", "arg2"
    }