Develop Reference

Delombok'ing source code with added jar dependencies

I am unable to delombok my Java source code, apparently due to jar dependencies that the project has, and I don't understand why. There are two jar files that have to be committed to the repo to tag along, and they are added to the project in the dependencies node of the build.gradle file by adding the line compile files('myproj1.jar'). So, the relevant part of the build.gradle file looks like this:
dependencies {
compile files('myproj1.jar')
compile files('myproj2.jar')
.....
}
When I run the delombok task I get the following error:
Execution failed for task ':delombok'.
> taskdef class lombok.delombok.ant.Tasks$Delombok cannot be found
using the classloader AntClassLoader[/path/to/repo/myproj1.jar:/path/to/repo/myproj2.jar]
Why would delombok task be using the AntClassLoader from the jar files?
I have tried the delombok'ing code from this post
Here is the task from my build.gradle file
def srcJava = 'src/main/java'
def srcDelomboked = 'build/src-delomboked'
task delombok {
// delombok task may depend on other projects already being compiled
dependsOn configurations.compile.getTaskDependencyFromProjectDependency(true, "compileJava")
// Set up incremental build, must be made in the configuration phase (not doLast)
inputs.files file(srcJava)
outputs.dir file(srcDelomboked)
doLast {
FileCollection collection = files(configurations.compile)
FileCollection sumTree = collection + fileTree(dir: 'bin')
ant.taskdef(name: 'delombok', classname: 'lombok.delombok.ant.Tasks$Delombok', classpath: configurations.compile.asPath)
ant.delombok(from:srcJava, to:srcDelomboked, classpath: sumTree.asPath)
}
}
I expect to be able to delombok my Java source code as part of the build process so that when the project is compiled there are no dependencies on Lombok.

So after continued trial an error, I have a working implementation. To answer my own question, the problem has nothing to do with the additional Jar files. Rather, when gradle runs the delombok task, the classes in the lombok jar are not in the classpath of the org.gradle.api.AntBuilder (ie, the ant task), and so it does not have a reference to lombok.delombok.ant.Tasks$Delombok anywhere (which seems obvious at this point, but not at the time).
The solution thus far has been to add those references in from configurations.compile
Combining code snippits from this post and this post you can do it with something like this:
def srcDelomboked = 'build/src-delomboked'
task delombok {
description 'Delomboks the entire source code tree'
def srcJava = 'src/main/java'
inputs.files files( srcJava )
outputs.dir file( srcDelomboked )
doFirst {
ClassLoader antClassLoader = org.apache.tools.ant.Project.class.classLoader
def collection = files( configurations.compile + configurations.testCompile )
def sumTree = collection + fileTree( dir: 'bin' )
sumTree.forEach { File file ->
antClassLoader.addURL(file.toURI().toURL())
}
ant.taskdef( name: 'delombok', classname: 'lombok.delombok.ant.Tasks$Delombok',
classpath: configurations.compile.asPath + configurations.testCompile.asPath )
ant.delombok( from: srcJava, to: srcDelomboked, classpath: sumTree.asPath )
}
}
sourceSets {
main {
java { srcDirs = [ srcDelomboked ] } //blow away the old source sets so that we only use the delomboked source sets
}
test {
java { srcDirs += [ srcDelomboked ] } //but add those new source sets to the tests so that their references are available at test time
}
}
compileJava.dependsOn(delombok)
bootJar {
mainClassName = 'com.myproj.MyMainClass' // you will need this if its a Spring Boot project
}
Hope this helps whomever else needs to delombok their code.

Gradle get file collection of parent directories

I'm trying to configure a task that will generate a single report from a collection of binary junit test results, but I'm unable to create a FileCollection containing the paths in which all the result files are located.
My task is defined like this
task aggregateTestREports(type: org.gradle.api.tasks.tests.TestSupport) {
destinationDir = reportDir
testResultsDirs = ???
}
Where the ??? is the part that I'm not getting to work.
I can use the following code to get a list of the output.bin files in our build structure, but I need to transform this into the list of the directories the files are in.
fileTree(dir: '.', includes: ['**/test-results/binary/test/output.bin'])
I've tried creating a custom class from the base class like this and passing the results of that line to the testOutputBinFiles parameter and calculating the files dynamically
class AggregateTestReport extends TestReport {
#Input
def testOutputBinFiles
def getTestResultDirs() {
def parents = []
testOutputBinFiles.each {
File file -> parents << file.parentFile.absoluteFile
}
parents
}
}
but this gives me an error that the return value is not compatible with a FileCollection
The docs for FileCollection indicate that the only way to get a new one is to use the files() function, but it isn't available from within the custom class to get a new file.

Due to an issue with the way the tests in my project are written taking on the dependency that is introduced by dnault's answer causes our tests to fail. Ultimately as we fix the issue in our project that causes this, his solution will work so I accepted that answer. For completeness, my stopgap solution ended up being
def resultPaths(FileCollection testOutputBinFiles) {
def parents = []
testOutputBinFiles.each {
File file -> parents << file.parentFile.absoluteFile
}
parents
}
task aggregateTestReports(type: org.gradle.api.tasks.testing.TestReport) {
destinationDir = reportDir
reportOn resultPaths(fileTree(dir: '.', includes: ['**/test-results/binary/test/output.bin']))
}

You can declare a task of type TestReport with a 'reportOn' property listing the Test tasks to aggregate:
task allTests(type: TestReport) {
destinationDir = file("${buildDir}/reports/allTests")
reportOn test, myCustomTestTask
}
This approach is outlined in section 7.3.3 of "Gradle in Action" by Benjamin Muschko (highly recommended reading).

How do I declare gradle Antlr task output specs to avoid unnecessary rebuilds

I have a typical Antlr 4.5 project with two grammar files: MyLexer.g4 and MyParser.g4. From them, Antlr generates 6 output files: MyLexer.java, MyLexer.tokens, MyParser.java, MyParser.tokens, MyParserBaseListener.java and MyParserListener.java. The gradle tasks are all working correctly so that the output files are all generated, compiled and tested as expected.
The problem is that gradle sees the 6 target files as always being out of date, so every run or debug session has to regenerate them and therefore has to recompile the main java project even if none of the source files have changed.
The gradle task which generates the file has the output spec defined as the folder into which the 6 output files are generated. I think that I need a way to define it as being the 6 specific files rather than the output folder. I just don't know the syntax to do that.
Here's the pertinent part of my build.gradle file:
ext.antlr4 = [
antlrSource: "src/main/antlr",
destinationDir: "src/main/java/com/myantlrquestion/core/antlr/generated",
grammarpackage: "com.myantlrquestion.core.antlr.generated"
]
task makeAntlrOutputDir << {
file(antlr4.destinationDir).mkdirs()
}
task compileAntlrGrammars(type: JavaExec, dependsOn: makeAntlrOutputDir) {
// Grammars are conveniently sorted alphabetically. I assume that will remain true.
// That ensures that files named *Lexer.g4 are listed and therefore processed before the corresponding *Parser.g4
// It matters because the Lexer must be processed first since the Parser needs the .tokens file from the Lexer.
// Also note that the output file naming convention for combined grammars is slightly different from separate Lexer and Parser grammars.
def grammars = fileTree(antlr4.antlrSource).include('**/*.g4')
def target = file("${antlr4.destinationDir}")
inputs.files grammars
// TODO: This output spec is incorrect, so this task is never considered up to date.
// TODO: Tweak the outputs collection so it is correct with combined grammars as well as separate Lexer and Parser grammars.
outputs.dir target
main = 'org.antlr.v4.Tool'
classpath = configurations.antlr4
// Antlr command line args are at https://theantlrguy.atlassian.net/wiki/display/ANTLR4/ANTLR+Tool+Command+Line+Options
args = ["-o", target,
"-lib", target,
//"-listener", //"-listener" is the default
//"-no-visitor", //"-no-visitor" is the default
"-package", antlr4.grammarpackage,
grammars.files
].flatten()
// include optional description and group (shown by ./gradlew tasks command)
description = 'Generates Java sources from ANTLR4 grammars.'
group = 'Build'
}
compileJava {
dependsOn compileAntlrGrammars
// this next line isn't technically needed unless the antlr4.destinationDir is not under buildDir, but it doesn't hurt either
source antlr4.destinationDir
}
task cleanAntlr {
delete antlr4.destinationDir
}
clean.dependsOn cleanAntlr

I discovered the problem was not that the target files were out of date, but rather, due to a bug in the cleanAntlr task, they were being deleted every time that any gradle task was run. The problem was that all of the code in cleanAntlr was being run during gradle's initialization and configuration phase, even if the cleanAntlr task itself wasn't being executed.
Originally, the task was defined as:
task cleanAntlr {
delete antlr4.destinationDir
}
clean.dependsOn cleanAntlr
The solution was to define it like this: (Note the "<<" after the task name.)
task cleanAntlr << {
delete antlr4.destinationDir
}
clean.dependsOn cleanAntlr
... or, for additional clarity, use this more verbose, but functionally equivalent task definition:
task cleanAntlr {
doLast() {
// Be sure to wrap the execution phase code inside doLast().
// Otherwise it will run during the initialization or configuration phase, even when an unrelated task is is run.
// It would also run when the NetBeas IDE first loaded the project.
//println 'Deleting Antlr Directory: ' + antlr4.destinationDir
delete antlr4.destinationDir
}
}
clean.dependsOn cleanAntlr
With that bug fixed, the original outputs specification for the compileAntlrGrammars task works correctly. There is no need to specify each individual output file. This is explained quite well in section 15.9.2 of https://gradle.org/docs/current/userguide/more_about_tasks.html.
def grammars = fileTree(antlr4.antlrSource).include('**/*.g4')
def target = file("${antlr4.destinationDir}")
inputs.files grammars
outputs.dir target

Could you please try the following piece of code:
generatedFiles = ['MyLexer.java',] // and so on..
generatedFiles.each { f -> outputs.file("$target/$f") }

Gradle task - pass arguments to Java application

I have a Java application that runs with a custom gradle task and the application requires some arguments upon being invoked. These are:
programName ( string | -f filename | -d key | -h)
Options:
string Message to be used.
-d key Use default messages, key must be s[hort], m[edium] or l[ong].
-f filename Use specified file as input.
-h Help dialog.
Gradle task looks like:
task run (type: JavaExec){
description = "Secure algorythm testing"
main = 'main.Test'
classpath = sourceSets.main.runtimeClasspath
}
I've tried running gradle run -h and it does not work.

Gradle 4.9+
gradle run --args='arg1 arg2'
This assumes your build.gradle is configured with the Application plugin. Your build.gradle should look similar to this:
plugins {
// Implicitly applies Java plugin
id: 'application'
}
application {
// URI of your main class/application's entry point (required)
mainClassName = 'org.gradle.sample.Main'
}
Pre-Gradle 4.9
Include the following in your build.gradle:
run {
if (project.hasProperty("appArgs")) {
args Eval.me(appArgs)
}
}
Then to run: gradle run -PappArgs="['arg1', 'args2']"

Since Gradle 4.9, the command line arguments can be passed with --args. For example, if you want to launch the application with command line arguments foo --bar, you can use
gradle run --args='foo --bar'
See Also Gradle Application Plugin
How to upgrade Gradle wrapper

If you want to use the same set of arguments all the time, the following is all you need.
run {
args = ["--myarg1", "--myarg2"]
}

Sorry for answering so late.
I figured an answer alike to #xlm 's:
task run (type: JavaExec, dependsOn: classes){
if(project.hasProperty('myargs')){
args(myargs.split(','))
}
description = "Secure algorythm testing"
main = "main.Test"
classpath = sourceSets.main.runtimeClasspath
}
And invoke like:
gradle run -Pmyargs=-d,s

You can find the solution in Problems passing system properties and parameters when running Java class via Gradle . Both involve the use of the args property
Also you should read the difference between passing with -D or with -P that is explained in the Gradle documentation

Of course the answers above all do the job, but still i would like to use something like
gradle run path1 path2
well this can't be done, but what if we can:
gralde run --- path1 path2
If you think it is more elegant, then you can do it, the trick is to process the command line and modify it before gradle does, this can be done by using init scripts
The init script below:
Process the command line and remove --- and all other arguments following '---'
Add property 'appArgs' to gradle.ext
So in your run task (or JavaExec, Exec) you can:
if (project.gradle.hasProperty("appArgs")) {
List<String> appArgs = project.gradle.appArgs;
args appArgs
}
The init script is:
import org.gradle.api.invocation.Gradle
Gradle aGradle = gradle
StartParameter startParameter = aGradle.startParameter
List tasks = startParameter.getTaskRequests();
List<String> appArgs = new ArrayList<>()
tasks.forEach {
List<String> args = it.getArgs();
Iterator<String> argsI = args.iterator();
while (argsI.hasNext()) {
String arg = argsI.next();
// remove '---' and all that follow
if (arg == "---") {
argsI.remove();
while (argsI.hasNext()) {
arg = argsI.next();
// and add it to appArgs
appArgs.add(arg);
argsI.remove();
}
}
}
}
aGradle.ext.appArgs = appArgs
Limitations:
I was forced to use '---' and not '--'
You have to add some global init script
If you don't like global init script, you can specify it in command line
gradle -I init.gradle run --- f:/temp/x.xml
Or better add an alias to your shell:
gradleapp run --- f:/temp/x.xml

You need to pass them as args to the task using project properties, something like:
args = [project.property('h')]
added to your task definition (see the dsl docs)
Then you can run it as:
gradle -Ph run

How to pass parameters to main method using Gradle?

I have to pass two arguments to my main method. My build script is
// Apply the java plugin to add support for Java
apply plugin: 'java'
// In this section you declare where to find the dependencies of your project
repositories {
// Use 'maven central' for resolving your dependencies.
mavenCentral()
}
// In this section you declare the dependencies for your production and test code
dependencies {
compile 'com.example:example-core:1.7.6'
}
task main(type: JavaExec, dependsOn: classes) {
description = 'This task will start the main class of the example project'
group = 'Example'
main = 'com.example.core.Example'
classpath = sourceSets.main.runtimeClasspath
}
If I try:
gradlew main doc.json text.txt
Then an error occured.
org.gradle.execution.TaskSelectionException: Task 'doc.json' not found in root project
How can I pass arguments to my main method command line easily?

task run(type: JavaExec) {
main = "pkg.MainClass"
classpath = sourceSets.main.runtimeClasspath
args = ["arg1", "arg2"]
}

You should use use -P as listed in the Gradle command line documentation.
For example, the following will work:
gradlew main -Parg1=doc.json --project-prop arg2=text.txt
And you access them in your Gradle script like this:
println "$arg1 $arg2"

task run1(type: JavaExec) {
main = "pkg.mainclass"
classpath = sourceSets.main.runtimeClasspath
args = ["$arg1","$arg2",...]
}
//I have named as run1 it can be any task name
While invoking the gradle script:
c:\> gradle run1 -Parg1="test123" -Parg2="sss"