How to extract common code from gradle jar task to a mthod - jar

Question

I have two task nativeJar and native64Jar, manifest and doLast closers are same for both the tasks except the file names. So is It possible to extract that code in a common method and pass two file names as a method parameter and call that common method from both tasks or call that method from dolast clouser.
task nativeJar( type: Jar ) {
doFirst {
delete fileTree(dir: "$releaseDir", include: "*.jar")
}
baseName = 'NativeLibs'
destinationDir = new File(releaseDir)
from files(releaseDir + 'jar_merge/signedNativeLibs')
manifest {
attributes 'Permissions' : 'all-permissions', 'Publisher' : 'abc', 'Application-Name' : 'WorkBench', 'Codebase' : '*.abc.com'
}
doLast {
ant.signjar( jar: "$releaseDir/NativeLibs.jar", alias:"WorkBench", keystore: "WorkBench.jks", signedjar: "$releaseDir/signedNativeLibs.jar", storepass: "freddie" )
}
}
// Create signedNativeLibs64.jar file
task native64Jar( type: Jar , dependsOn: 'nativeJar' ) {
baseName = 'NativeLibs64'
destinationDir = new File(releaseDir)
from files(releaseDir + 'jar_merge/signedNativeLibs64')
manifest {
attributes 'Permissions' : 'all-permissions', 'Publisher' : 'abc', 'Application-Name' : 'WorkBench', 'Codebase' : '*.abc.com'
}
doLast {
ant.signjar( jar: "$releaseDir/NativeLibs64.jar", alias:"WorkBench", keystore: "WorkBench.jks", signedjar: "$releaseDir/signedNativeLibs64.jar", storepass: "freddie" )
}
}

Answer 1

I would recommend splitting out the signing as a separate task so that you get proper up-to-date checks from Gradle. As you have it now, you'll always sign the jar every time you build. And if you delete the signed jar, it won't generate again until you clean the native jar too.
You can share configuration closures between tasks. E.g.,
[ task1, task2 ].each { task ->
task.configure {
// shared closure
}
}
There are a few other best practices I'd follow.
Don't use new File() since it makes your script dependent on the current working directory.
Refer to outputs via the task versus recreating the full path (e.g., what you're doing with $releaseDir/NativeLibs.jar). Gradle is able to infer dependencies that way.
Use a custom task class vs an ad-hoc task with doFirst()/doLast(). Since you're delegating all the work to the ant task, this should be really simple.
I'm not sure why you need your particular file names, but I left them as-is. If they're not important, removing them would make this even simpler.
I took a stab at your example (disclaimer: I didn't try it):
task nativeJar( type: Jar ) {
baseName = 'NativeLibs'
from files(releaseDir + 'jar_merge/signedNativeLibs')
}
task native64Jar( type: Jar ) {
baseName = 'NativeLibs64'
from files(releaseDir + 'jar_merge/signedNativeLibs64')
}
[ nativeJar, native64Jar ].each { task ->
task.configure {
destinationDir = file(releaseDir)
manifest {
attributes 'Permissions' : 'all-permissions', 'Publisher' : 'Financial Engineering', 'Application-Name' : 'WorkBench', 'Codebase' : '*.fhlmc.com'
}
}
}
// this class definition should go at the top of your build.gradle script else it will through an exception mentioned in comments
class SignJarTask extends DefaultTask {
#InputFile File inputFile
#OutputFile File outputFile
#TaskAction
void signJar() {
ant.signjar( jar: inputFile, alias:"WorkBench", keystore: "WorkBench.jks", signedjar: outputFile, storepass: "freddie" )
}
}
task signJar(type: SignJarTask) {
inputFile = file("$releaseDir/NativeLibs.jar")
outputFile = file("$releaseDir/signedNativeLibs.jar")
}
task sign64Jar(type: SignJarTask) {
inputFile = file("$releaseDir/NativeLibs64.jar")
outputFile = file("$releaseDir/signedNativeLibs64.jar")
}