Develop Reference

How can you add dependency source code to sourceJar task output?

If you got a multi-project gradle build. And one module depends on another.
How could you add the dependency module source code to the output jar
Now i am using this:
java {
withSourcesJar()
}
I am new to gradle builds and i don't know any kotlin.
And if you have the source code of a dependency as a .jar file. Could you also add that
to the output?
So I have a project module:
dependencies:
project module
local .jar
What i want:
One .jar of the project (including other modules and dependencies) compiled code:
project-0.5.0.jar
..and one .jar of the source code (including other modules and dependencies)
project-0.5.0-sources.jar
I have all source code of dependencies stored locally as .jar files
Edit
My project conventions (global for all modules):
plugins {
`java-library`
}
java {
withSourcesJar()
}
How I am currently creating the project "fat".jar with compiled code:
(inside the build script)
tasks.jar {
//manifest.attributes["Main-Class"] = "com.example.MyMainClass"
val dependencies = configurations
.runtimeClasspath
.get()
.map(::zipTree) // OR .map { zipTree(it) }
from(dependencies)
duplicatesStrategy = DuplicatesStrategy.EXCLUDE
}
I have figured out how to add a project moduleA to another moduleB output sources .jar like so (inside moduleB's build-script):
tasks.sourcesJar {
from(project(":moduleA").sourceSets.main.get().allSource)
}
Now I need to figure out how to include source code from a dependency .jar
from(file("../path/dependency-1.0.0-sources.jar"))
This packs the .jar as it is. I need it's files.

I figured it out. And it was easier than i thought. Keep in mind i am using Kotlin.
(All code snippets are inside the build.gradle.kts file of the project / module you are creating the sources .jar for)
First off you need to include either the java or java-library plugin:
plugins {
`java-library`
}
And as far as i know, also this plugin extension:
java {
withSourcesJar()
}
This makes the sourcesJar task available (task used to create the sources jar), and you can modify it like so:
tasks.sourcesJar {
from(project(":common").sourceSets.main.get().allSource)
from(zipTree("../libs/tinylog-2.5.0/tinylog-api-2.5.0-sources.jar"))
}
The first line inside the brackets includes my "common" module source code to the output .jar.
The second line adds the .java files inside the tinylog sources .jar to the output .jar.

Gradle: multiple JARs without multiple projects

I have a library which is used to build a number of CLI tools using Gradle. Each CLI tool is a separate JAR. At the moment every tool requires a separate Gradle project, with an associated set of directories, like this:
Having all of this structure is resulting in the whole collection of tools becoming very unwieldy and difficult to work with. Is there any way to collect all of the different Mains into a single folder (suitably renamed) and configure Gradle to turn each one into a separate JAR?
FWIW, the JARs are currently created using https://github.com/johnrengelman/shadow . JAR size doesn't matter.
Thanks in advance.

Jars are just zip files with META-INF folder inside. Use Zip tasks to create them and dependsOn to run tasks as part of your build sequence.
I had the code like below for changing jar files:
task changeJar (type: Zip) {
baseName project.name
extension 'jar'
destinationDir new File('build')
entryCompression ZipEntryCompression.STORED
from { zipTree(new File(core.libsDir, core.name + '.jar')) }
from ( <somewhere else> ) {
exclude 'META-INF/'
}
}

I'm not sure if it's a good fit but you might be interested in my gradle-java-flavours plugin.
eg:
apply plugin: 'com.lazan.javaflavours'
javaFlavours {
flavour 'tool1'
flavour 'tool2'
}
dependencies {
compile 'a:a:1.0' // common to all tools
compileTool1 'b:b:2.0' // compile deps for tool1 only
runtimeTool2 'c:c:2.0' // runtime deps for tool2 only
}
Directories
src/main/java, src/test/java, src/main/resources, src/test/resources - common code & tests
src/tool1/java, src/testTool1/java, src/tool1/resources, src/testTool1/resources - tool1 only sources
src/tool2/java, src/testTool2/java, src/tool2/resources, src/testTool2/resources - tool2 only sources
Jars
projectName.jar
projectName-tool1.jar
projectName-tool2.jar

filter gradle configuration for specific libraries

I am currently about to migrate the build system for my project from ANT to gradle. So I am pretty new to gradle My project features a plugin mechanism that dynamically loads jars configured in an XML file. Each plugin is in its own subproject. The entries of the XML configuration look as follows
<?xml version="1.0" encoding="UTF-8"?>
<implementation ...>
<repository>text</repository>
<classpath>library1.jar</classpath>
<classpath>library2.jar</classpath>
...
</implementation>
I added an XSL transformation to prefix each entry with the correct lib folder in the build folder to make it usable in a run task of my main project.
This already works OK for the libraries that are created within my project. However, some of them rely on third party libraries, e.g., protobuf.
For now, I solved this by copying all referenced jars to the lib folder. My build.gradle looks as follows
dependencies {
compile group: 'com.google.protobuf', name: 'protobuf-java', version: '3.1.0'
...
compile project(':main')
}
task copyReferencedLibraries(type: Copy) {
into "$buildDir/libs"
from configurations.compile
}
jar {
dependsOn xslt
dependsOn copyReferencedLibraries
...
}
However, this copies all libraries, including those inherited from the main project to the lib folder. More than I actually need.
How could I filter the libraries to those defined in this subproject or at least manually filter the ones that I want to be copied?

You could just filter in your Copy task
task copyReferencedLibraries(type: Copy) {
into "$buildDir/libs"
from(configurations.compile) {
exclude 'some.jar', 'some-other.jar'
include 'some-required.jar', 'some-other-required.jar'
}
}
Reference: https://docs.gradle.org/current/dsl/org.gradle.api.tasks.Copy.html
Just be careful you don't exclude second or third tier dependency (ie a jar required by a jar your using). If you do then you won't get compile errors you will get runtime errors when the code is executed that touches the missing dependency.

Choose Directory for Gradle Generated Source Code

I'm using Dagger 2 to generate some source code in my Gradle project. Right now those sources are being generated and added in the ./build/classes/main folder along with all the class files.
How do I choose a folder to separate all the generated .java files to?
How do I include that folder in my gradle Java project, and have IntelliJ view those as sources so I can use them in my project?

It looks like the application plugin only uses a certain set of directories by default, mixing in flavours of build to decide what files to compile.
However, I did find an example build script that creates a dagger configuration and manipulates gradle into using it for the generated output and adds it to the classpath. It uses dagger-compiler.
The core of it is:
sourceSets {
dagger {
java {
srcDirs = ['src/dagger/java']
}
}
}
configurations {
compileDagger
}
compileJava {
description = "dagger annotation processor is loaded automatically from classpath"
sourceSets.dagger.java.srcDirs*.mkdirs()
classpath += configurations.compileDagger
options.compilerArgs += [
'-s', sourceSets.dagger.java.srcDirs.iterator().next()
]
}
clean {
description = "delete files in generated source directory tree"
delete fileTree(dir: sourceSets.dagger.java.srcDirs.iterator().next())
}
dependencies {
ext.daggerVersion = "2.0.1"
compile(
"com.google.dagger:dagger:${daggerVersion}",
"com.google.guava:guava:18.0")
compileDagger(
"com.google.dagger:dagger-compiler:${daggerVersion}")
}
Regarding IntelliJ, the plugin should automatically add any srcSets via the normal building of the idea project, so there should be no additional configuration needed, just regenerate it.

Using Gradle with native dependencies

I am trying to use Sigar in a Gradle project. Sigar distribution is by default provided with 2 types of files:
a JAR that contains classes
some native files (.so, dylib, .dll)
My purpose is to repackage these files so that I can use them as dependencies deployed and downloaded on-demand from a personal Maven repository.
My first try was to define dependencies as files in order to check that my application is working as expected before to repackage. Below is the Gradle code I used for my first test that works:
dependencies {
compile files("${rootDir}/lib/sigar/sigar.jar")
runtime fileTree(dir: "${rootDir}/lib/sigar/", exclude: "*.jar")
}
Then, I have repackaged Sigar native files into a JAR and renamed the other one to match rules for maven artifacts since I want to deploy them in a Maven repository. Below is what I get:
sigar-1.6.4.jar (contains .class files)
sigar-1.6.4-native.jar (contains .dylib, .so, and .dll files at the root)
The next step was to deploy these files in my custom repository. Then, I have updated my build.gradle as follows:
dependencies {
compile 'sigar:sigar:1.6.4'
runtime 'sigar:sigar:1.6.4:native'
}
Unfortunately, when I do a gradle clean build, new dependencies are fetched but native libraries can no longer be found at runtime since now I get the following exception:
Error thrown in postRegister method: rethrowing <java.lang.UnsatisfiedLinkError: org.hyperic.sigar.Sigar.getCpuInfoList()[Lorg/hyperic/sigar/CpuInfo;>
Consequently, I am looking for a solution to fetch and to link native files to my Java app like for other dependencies. Any advice, comment, suggestion, help, solution, etc. are welcome ;)

A solution is to define a new gradle configuration that unzips JAR files at the desired location:
project.ext.set('nativeLibsDir', "$buildDir/libs/natives")
configurations {
nativeBundle
}
dependencies {
nativeBundle 'sigar:sigar:1.6.4:native'
}
task extractNativeBundle(type: Sync) {
from {
configurations.nativeBundle.collect { zipTree(it) }
}
into file(project.nativeLibsDir)
}
dist.dependsOn extractNativeBundle
Then, this location must be put in java.library.path for tasks that depend on native libraries:
systemProperty "java.library.path", project.nativeLibsDir