Gradle start script: Hide console

Question

I'm using the Gradle application plugin for my Java app.

The start scripts Gradle generates work fine but I'd prefer if the console wouldn't pop up when the user starts the application.

Is there a way to do this?

Answer 1

By modifying the start script I got what I wanted (just for Windows for now).

build.gradle:

apply from: "IO.gradle"

// Modify the Windows start script so that no console is shown when the user starts the app.
// This also creates a copy of the original start script in case we want to use the console for debugging
startScripts << { 

  def startScriptDir = outputDir.getAbsolutePath()
  def winStartScript = startScriptDir + "/" + applicationName + ".bat"
  def winStartScriptCopy = startScriptDir + "/" + applicationName + "WithConsole.bat"
  def overwriteExistingFile = true
  copyFile(winStartScript, winStartScriptCopy, overwriteExistingFile)

  modifyFile(winStartScript) {
    // javaw.exe doesn't have a console
    if(it.contains("java.exe")){
      return it.replace("java.exe", "javaw.exe")
    }
    // Command that launches the app
    else if(it.startsWith("\"%JAVA_EXE%\" %DEFAULT_JVM_OPTS%")){
      return "start \"\" /b " + it
    }
    // Leave the line unchanged
    else{
      return it
    }
  }
}
installApp {
  // Include the additional start script
  into("bin/"){
    from(startScripts.outputDir)
  }
}

IO.gradle:

import java.nio.*
import java.nio.file.*

/**
 * This will completely re-write a file, be careful.
 * 
 * Simple Usage:
 *
 * modifyFile("C:\whatever\whatever.txt") {
 *   if(it.contains("soil"))
 *      return null  // remove dirty word
 *   else
 *      return it
 * }
 *
 * The closure must return the line passed in to keep it in the file or alter it, any alteration
 * will be written in its place.
 *
 * To delete an entire line instead of changing it, return null
 * To add more lines after a given line return: it + "\n" + moreLines
 *
 * Notice that you add "\n" before your additional lines and not after the last
 * one because this method will normally add one for you.
 */
def modifyFile(srcFile, Closure c) {
    modifyFile(srcFile, srcFile, c)
}

def modifyFile(srcFile, destFile, Closure c={println it;return it}) {
  StringBuffer ret = new StringBuffer();
  File src = new File(srcFile)
    File dest = new File(destFile)

    src.withReader{reader->
      reader.eachLine{
        def line=c(it)
        if(line != null) {
          ret.append(line)
          ret.append("\n")
        }
      }
    }
  dest.delete()
  dest.write(ret.toString())
}


/**
* Copies a file specified at 'origin' to 'destination'.
* If 'overwrite' is set to true any existing file at 'destination' is overwritten (defaults to false).
*/
def copyFile(String origin, String destination, boolean overwrite=false){

  Path origPath = Paths.get(origin)
  Path destPath = Paths.get(destination)
  def fileAtDestination = destPath.toFile()
  if(fileAtDestination.exists()){
    if(overwrite) {
      fileAtDestination.delete() 
      Files.copy(origPath, destPath)
    }
    else{
      println("Won't overwrite existing file $fileAtDestination")       
      println("Call 'copyFile(orig, dest, true)' to delete the existing file first")       
    }
  }
  else {
      // There's no file at the destination yet
      Files.copy(origPath, destPath)
  }
}

// Define methods visible to other Gradle scripts
ext{
  modifyFile = this.&modifyFile
  copyFile = this.&copyFile
}

modifyFile is authored by Bill K.