When calling gradle idea, external dependencies are ordered first in the class path relatively to local Jar inclusions. As such :
dependencies {
compile fileTree(dir: 'libs', include:['*.jar'])
compile group: 'foo', name:'bar', version:'1.0.0'
}
will include my local jars last. This is a problem in my project as these jars' purpose is to partially overwrite the external library.
The same behavior is observed when specifying the repository as a source of dependencies using flatDir and loading the jar without fileTree. It is put last in the classpath.
I have found several mentions of the problem when researching, such as https://discuss.gradle.org/t/gradle-messes-up-the-classpath-order-in-generated-projects-when-there-are-mixed-dependency-types/13130, but no workarounds.
I suppose these exist, gradle being very customisable, but being very new to it my attempts to make one fail. How to proceed?
I'm not using IntelliJ on a regular basis but tried it in the context of this question and my impression is that gradle's idea plugin and IntelliJ's gradle plugin don't go well together. That is you should either use the idea gradle plugin and import as plain Java project or import as gradle project using IntelliJ's gradle plugin. Main reason is that the idea plugin and the IntelliJ plugin are generating slightly different iml-files (those files are holding the project dependencies - amongst others) which leads to lot of confusion when using both plugins together. As you specifically asked for the gradle idea plugin, I used this plugin and imported into IntelliJ as plain java project.
But to answer your question I found no evidence that the order of libraries on the classpath differs from the order as declared in the dependencies section of the gradle file, when using a flatDir repo. When using compile fileTree(dir: 'libs', include:['*.jar']) the order was actually broken as described in your question. That is, you should stick to using a flatDir repo.
I'm using gradle 4.9 and IntelliJ 2018.2.
This is my gradle file
apply plugin: 'java'
apply plugin: 'idea'
repositories {
jcenter()
flatDir {
dirs 'libs'
}
}
dependencies {
compile 'zzz:zzz-0.0.0'
compile 'aaa:aaa-0.0.0'
compile 'com.google.guava:guava:24.0-jre'
compile group: 'javax.websocket', name: 'javax.websocket-api', version: '1.1'
}
task wrapper(type: Wrapper) {
gradleVersion = '4.9'
distributionUrl = "http://services.gradle.org/distributions/gradle-${gradleVersion}-bin.zip"
}
In my libs folder there are two jars aaa-0.0.0.jar and zzz-0.0.0.jar both are copies of guava-24.0-jre.jar. That is all guava classes are present in both jars as well. As zzz:zzz-0.0.0 is the first dependency in the gradle file, the expectation would be that guava classes are being loaded from zzz-0.0.0.jar instead of guava-24.0-jre.jar or aaa-0.0.0.jar. I used the following main class to test this:
package test;
import com.google.common.math.LongMath;
public class Test {
public static void main(String[] args) throws Exception {
System.out.println(LongMath.class.getProtectionDomain().getCodeSource().getLocation().toURI());
}
}
And the output when running it from IntelliJ is
file:/C:/ws/gradle-idea-test/libs/zzz-0.0.0.jar
That is the com.google.common.math.LongMath class is indeed being loaded from the local libs/zzz-0.0.0.jar instead of the guava-24.0-jre.jar.
I noticed that the list of external dependencies in IntelliJ doesn't show the local libraries. And even more confusing the libraries are ordered alphabetically and don't reflect the actual order on the classpath which might be quite confusing:
To get the actual order of elements on the classpath you will have to look in the module dependencies section in the module settings ("Open Module Settings" > "Project" > "Modules" > "Dependencies Tab") which looks like this:
As you can see the dependencies are listed in correct order and include the local libraries as well. The order of libs in this dialog is basically the same as in the generated iml-file.
When using the IntelliJ gradle plugin instead of gradle's idea plugin, IntelliJ basically behaved the same way but the generated iml-file looked different and the external libraries were displayed in a different format. But there was no difference regarding the classpath order.
We currently deliver an Android AAR sdk that we ask users to import and add as a compile time dependency.
We recently set up SonaQube and Jacoco; so the AAR itself uses the Jacoco Plugin for test code coverage.
We have a couple of demo apps that consume the AAR to ensure compatibility.
The Issue
The issue we are now facing is this bug Here which is namely:
java.lang.ClassNotFoundException: Didn't find class "org.jacoco.agent.rt.internal_14f7ee5.Offline"
and
java.lang.NoClassDefFoundError: Failed resolution of: Lorg/jacoco/agent/rt/internal_14f7ee5/Offline;
The issue occurs at runtime when the consuming App of the AAR starts up.
Workaround
I have set up the workaround provided in the above bug, namely forcing the APP build scripts for all APP projects to use the same jacoco version and to also include the jacoco group (agent, ant, core, and report) as compile time dependencies.
// App build.gradle
dependencies {
compile(project(path: ':TheAARInQuestion')) {
transitive false
}
....
compile "org.jacoco:org.jacoco.agent:$jacoco_version"
compile "org.jacoco:org.jacoco.ant:$jacoco_version"
compile "org.jacoco:org.jacoco.core:$jacoco_version"
compile "org.jacoco:org.jacoco.report:$jacoco_version"
}
// Top level build.gradle buildscript
buildscript {
def jacoco_version = '0.7.6.201602180812'
dependencies {
....
classpath "org.jacoco:org.jacoco.agent:$jacoco_version"
classpath "org.jacoco:org.jacoco.ant:$jacoco_version"
classpath "org.jacoco:org.jacoco.core:$jacoco_version"
classpath "org.jacoco:org.jacoco.report:$jacoco_version"
}
allprojects {
configurations.all {
resolutionStrategy {
force "org.jacoco:org.jacoco.agent:$jacoco_version"
force "org.jacoco:org.jacoco.ant:$jacoco_version"
force "org.jacoco:org.jacoco.core:$jacoco_version"
force "org.jacoco:org.jacoco.report:$jacoco_version"
}
}
}
}
My Question
I only want to apply jacoco and use the jacoco libraries in the test phase, IE testCompile only for the AAR build cycle so that consumers of the AAR do not need to do the above setup as it might conflict with their APK build process.
How can I only require the dependencies needed for testing only during test and not need them on the class path for the actual runtime implementation of the AAR?
IE I want to deliver an AAR that does not need customers to have jars on the class path nor do extra compile time dependencies. Is this possible?
EDIT 1
After reading up on jacoco further it appears that jacoco relies on JavaAgents which in turn are not supported fully by Dalvik VM(Android). Jacoco does have an offline mode but the gradle plugin does not support it out of the box. There is a feature request for it though here.
With this knowledge I have conditionally applied the plugin and tasks based on a property for when I want to run analysis in my build.gradle.
I have an Android project and I plan to make one of its components a library. This will be a Java library (jar), as the android dependencies are not needed there.
The problem is that this library depends on RxJava. But I would like it to be dependent on the RxJava version which the library client will use, no to be explicitly provided by me in the library's build.gradle.
I thought that maybe Gradle Default dependencies would be the way to go, but it doesn't provide the RxJava dependency at all and the library module doesn't build.
My build.gradle:
apply plugin: 'java'
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
}
configurations.all {
pluginTool {
defaultDependencies { dependencies ->
dependencies.add(this.project.dependencies.create("io.reactivex:rxjava:1.1.0"))
}
}
}
sourceCompatibility = "1.7"
targetCompatibility = "1.7"
The problem is that this library depends on RxJava. But I would like it to be dependent on the RxJava version which the library client will use, no to be explicitly provided by me in the library's build.gradle.
I don't know if that's possible because that's not the way dependencies work. Maven Transitive Dependencies explains this issue a little.
For example, you made a library and used a given version of RxJava, say, vn. It implictly means that your lib uses some features of vn that are not present in vn-1 and hopefully won't be deprecated in vn+1 and later. If a lib client were able to choose any RxJava version, it could arbitrarily pick vn-1 and your code would not work. You have a hard dependency on vn and anyone who uses your library should be aware of it.
There's no problem in providing an explicit dependency in your lib's build.gradle. In fact, listing the dependencies will help Gradle resolve the dependency graph, handle conflicts and everything. Here's a bit of what Gradle does: https://docs.gradle.org/current/dsl/org.gradle.api.artifacts.ResolutionStrategy.html
Finally, even if you find a way to achieve the dependency delegation to the lib client, the application can crash during runtime.
To add a simple dependency on test source sets from an another subproject I can do:
testCompile project(':subFoo1').sourceSets.test.output
This solution works, but in many cases it is not intended to add the whole source set as a dependency. For example I would like to use only test data builders and in that case files like test-logback.xml (and regular tests) pollute my test classpath in the master module.
I tried the idea with test JAR (which can have filtered content, but is problematic as a dependency) and some combination with eachFileRecurse, but with no luck.
My question. How can I add only a subset of given source set(s) (e.g. only classes with builders matching **/*Builder.* pattern) as a testCompile dependency in another subproject?
You'll want something along the lines of:
upstream/build.gradle:
apply plugin: "java"
task testJar(type: Jar) {
classifier = "tests"
from sourceSets.test.output
exclude "**/*Test.class"
}
artifacts {
testRuntime testJar
}
downstream/build.gradle:
apply plugin: "java"
dependencies {
testCompile project(path: ":upstream", configuration: "testRuntime")
}
Instead of using testRuntime, you could also declare (e.g. configurations { testFixture }) and use a custom configuration, which would give you more control over which external dependencies are passed on to downstream projects. Yet another option would be to declare a separate source set for the part of the test code that is to be passed on. (This would also give you separate compile and runtime configurations to work with.)
PS: Reaching out into another project's object model (e.g. project(':subFoo1').sourceSets.test.output) is problematic, and should be avoided when possible.
I have a multi-project configuration and I want to use gradle.
My projects are like this:
Project A
-> src/main/java
-> src/test/java
Project B
-> src/main/java (depends on src/main/java on Project A)
-> src/test/java (depends on src/test/java on Project A)
My Project B build.gradle file is like this:
apply plugin: 'java'
dependencies {
compile project(':ProjectA')
}
The task compileJava work great but the compileTestJava does not compile the test file from Project A.
Deprecated - For Gradle 5.6 and above use this answer.
In Project B, you just need to add a testCompile dependency:
dependencies {
...
testCompile project(':A').sourceSets.test.output
}
Tested with Gradle 1.7.
This is now supported as a first class feature in Gradle. Modules with java or java-library plugins can also include a java-test-fixtures plugin which exposes helper classes and resources to be consumed with testFixtures helper. Benefit of this approach against artifacts and classifiers are:
proper dependency management (implementation/api)
nice separation from test code (separate source set)
no need to filter out test classes to expose only utilities
maintained by Gradle
Example
:modul:one
modul/one/build.gradle
plugins {
id "java-library" // or "java"
id "java-test-fixtures"
}
modul/one/src/testFixtures/java/com/example/Helper.java
package com.example;
public class Helper {}
:modul:other
modul/other/build.gradle
plugins {
id "java" // or "java-library"
}
dependencies {
testImplementation(testFixtures(project(":modul:one")))
}
modul/other/src/test/java/com/example/other/SomeTest.java
package com.example.other;
import com.example.Helper;
public class SomeTest {
#Test void f() {
new Helper(); // used from :modul:one's testFixtures
}
}
Further reading
For more info, see the documentation:
https://docs.gradle.org/current/userguide/java_testing.html#sec:java_test_fixtures
It was added in 5.6:
https://docs.gradle.org/5.6/release-notes.html#test-fixtures-for-java-projects
Simple way is to add explicit task dependency in ProjectB:
compileTestJava.dependsOn tasks.getByPath(':ProjectA:testClasses')
Difficult (but more clear) way is to create additional artifact configuration for ProjectA:
task myTestsJar(type: Jar) {
// pack whatever you need...
}
configurations {
testArtifacts
}
artifacts {
testArtifacts myTestsJar
}
and add the testCompile dependency for ProjectB
apply plugin: 'java'
dependencies {
compile project(':ProjectA')
testCompile project(path: ':ProjectA', configuration: 'testArtifacts')
}
I've come across this problem myself recently, and man is this a tough issues to find answers for.
The mistake you are making is thinking that a project should export its test elements in the same way that it exports its primary artifacts and dependencies.
What I had a lot more success with personally was making a new project in Gradle. In your example, I would name it
Project A_Test
-> src/main/java
I would put into the src/main/java the files that you currently have in Project A/src/test/java. Make any testCompile dependencies of your Project A compile dependencies of Project A_Test.
Then make Project A_Test a testCompile dependency of Project B.
It's not logical when you come at it from the perspective of the author of both projects, but I think it makes a lot of sense when you think about projects like junit and scalatest (and others. Even though those frameworks are testing-related, they are not considered part of the "test" targets within their own frameworks - they produce primary artifacts that other projects just happen to use within their test configuration. You just want to follow that same pattern.
Trying to do the other answers listed here did not work for me personally (using Gradle 1.9), but I've found that the pattern I describe here is a cleaner solution anyway.
I know it's an old question but I just had the same problem and spent some time figuring out what is going on. I'm using Gradle 1.9. All changes should be in ProjectB's build.gradle
To use test classes from ProjectA in tests of ProjectB:
testCompile files(project(':ProjectA').sourceSets.test.output.classesDir)
To make sure that sourceSets property is available for ProjectA:
evaluationDependsOn(':ProjectA')
To make sure test classes from ProjectA are actually there, when you compile ProjectB:
compileTestJava.dependsOn tasks.getByPath(':ProjectA:testClasses')
Please read the update bellow.
Similar problems described by JustACluelessNewbie occurs in IntelliJ IDEA. Problem is that dependency testCompile project(':core').sourceSets.test.output actually means: "depend on classes generated by gradle build task". So if you open clean project where classes are not generated yet IDEA won't recognise them and reports error.
To fix this problem you have to add a dependency on test source files next to dependency on compiled classes.
// First dependency is for IDEA
testCompileOnly files { project(':core').sourceSets.test.java.srcDirs }
// Second is for Gradle
testCompile project(':core').sourceSets.test.output
You can observe dependencies recognised by IDEA in Module Settings -> Dependencies (test scope).
Btw. this is not nice solution so refactoring is worth considering. Gradle itself does have special subproject containing test-support classes only. See https://docs.gradle.org/current/userguide/test_kit.html
Update 2016-06-05
More I am thinking about proposed solution less I like it. There are few problems with it:
It creates two dependencies in IDEA. One points to test sources another to compiled classes. And it is crucial in which order these dependencies are recognised by IDEA. You can play with it by changing dependency order in Module settings -> Dependencies tab.
By declaring these dependencies you are unnecessarily polluting dependency structure.
So what's the better solution? In my opinion it's creating new custom source set and putting shared classes into it. Actually authors of Gradle project did it by creating testFixtures source set.
To do it you just have to:
Create source set and add necessary configurations. Check this script plugin used in Gradle project: https://github.com/gradle/gradle/blob/v4.0.0/gradle/testFixtures.gradle
Declare proper dependency in dependent project:
dependencies {
testCompile project(path: ':module-with-shared-classes', configuration: 'testFixturesUsageCompile')
}
Import Gradle project to IDEA and use the "create separate module per source set" option while importing.
New testJar based (trnsitive dependancies supported) solution available as gradle plugin:
https://github.com/hauner/gradle-plugins/tree/master/jartest
https://plugins.gradle.org/plugin/com.github.hauner.jarTest/1.0
From documentation
In case you have a multi-project gradle build you may have test
dependencies between sub-projects (which probably is a hint that your
projects are not well structured).
For example assume a project where the sub-project Project B depends
on Project A and B does not only have a compile dependency on A but
also a test dependency. To compile and run the tests of B we need some
test helper classes from A.
By default gradle does not create a jar artifact from the test build
output of a project.
This plugin adds a testArchives configuration (based on testCompile)
and a jarTest task to create a jar from the test source set (with the
classifier test added to name of the jar). We can then depend in B on
the testArchives configuration of A (which will also include the
transitive dependencies of A).
In A we would add the plugin to build.gradle:
apply plugin: 'com.github.hauner.jarTest'
In B we reference the
testArchives configuration like this:
dependencies {
...
testCompile project (path: ':ProjectA', configuration: 'testArchives')
}
The Fesler's solution haven't worked for me, when i tried it to build an android project (gradle 2.2.0).
So i had to reference required classes manually :
android {
sourceSets {
androidTest {
java.srcDir project(':A').file("src/androidTest/java")
}
test {
java.srcDir project(':A').file("src/test/java")
}
}
}
Here if you are using Kotlin DSL, you should create your task like that according to Gradle documentation.
Like some previous answer, you need to create a special configuration inside the project that will share its tests class, so that you don't mix test and main classes.
Simple steps
In project A you would need to add in your build.gradle.kts :
configurations {
create("test")
}
tasks.register<Jar>("testArchive") {
archiveBaseName.set("ProjectA-test")
from(project.the<SourceSetContainer>()["test"].output)
}
artifacts {
add("test", tasks["testArchive"])
}
Then in your project B in the dependencies, you will need to add in your build.gradle.kts:
dependencies {
implementation(project(":ProjectA"))
testImplementation(project(":ProjectA", "test"))
}
I'm so late to the party (it is now Gradle v4.4) but for anyone else who finds this:
Assuming:
~/allProjects
|
|-/ProjectA/module-a/src/test/java
|
|-/ProjectB/module-b/src/test/java
Go to the build.gradle of project B (the one that needs some test classes from A) and add the following:
sourceSets {
String sharedTestDir = "${projectDir}"+'/module-b/src/test/java'
test {
java.srcDir sharedTestDir
}
}
or (assuming your project is named ProjectB)
sourceSets {
String sharedTestDir = project(':ProjectB').file("module-b/src/test/java")
test {
java.srcDir sharedTestDir
}
}
Voila!
Creating test-jar For Gradle 6.6.x
I know that there are many sources telling you, that is not OK, fe:
https://github.com/gradle/gradle/issues/11280
https://gradle.org/whats-new/gradle-6/#better-builds
But this is so damn simple and I just don't like the idea of having common test classes separately in testFixtures folder.
So in module A:
task jarTests(type: Jar, dependsOn: testClasses) {
classifier = 'tests'
from sourceSets.test.output
}
configurations {
tests {
extendsFrom testRuntime
}
}
artifacts {
tests jarTests
}
And in module B:
testImplementation project(':moduleA')
testImplementation project(path: ':moduleA', configuration: 'tests')
And it just works!
If you want to use artifact dependencies to have:
ProjectB's source classes depend on Project A's source classes
ProjectB's test classes depend on Project A's test classes
then ProjectB's dependencies section in build.gradle should look something like this:
dependencies {
compile("com.example:projecta:1.0.0")
testCompile("com.example:projecta:1.0.0:tests")
}
For this to work ProjectA needs to build a -tests jar and include it in the artifacts it produces.
ProjectA's build.gradle should contain configuration like this:
task testsJar(type: Jar, dependsOn: testClasses) {
classifier = 'tests'
from sourceSets.test.output
}
configurations {
tests
}
artifacts {
tests testsJar
archives testsJar
}
jar.finalizedBy(testsJar)
When ProjectA's artifacts are published to your artifactory they will include a -tests jar.
The testCompile in ProjectB's dependencies section will bring in the classes in the -tests jar.
If you want to includeFlat ProjectA's source and test classes in ProjectB for development purposes then the dependencies section in ProjectB's build.gradle would look like this:
dependencies {
compile project(':projecta')
testCompile project(path: ':projecta', configuration: 'tests')
}
If you have mock dependencies which you need to share between tests, you can create new project projectA-mock and then add it as test dependency to ProjectA and ProjectB:
dependencies {
testCompile project(':projectA-mock')
}
This is clear solution to share mock dependencies, but if you need to run tests from ProjectA in ProjectB use other solution.
The solution mentioned by Nikita for Android + Kotlin looks like this:
task jarTests(type: Jar, dependsOn: "assembleDebugUnitTest") {
getArchiveClassifier().set('tests')
from "$buildDir/tmp/kotlin-classes/debugUnitTest"
}
configurations {
unitTestArtifact
}
artifacts {
unitTestArtifact jarTests
}
Gradle for project that is going to use dependencies:
testImplementation project(path: ':shared', configuration: 'unitTestArtifact')
If you are struggling to adapt the solution to the Gradle Kotlin DSL this is the equivalent:
configurations {
register("testClasses") {
extendsFrom(testImplementation.get())
}
}
val testJar = tasks.register<Jar>("testJar") {
archiveClassifier.set("test")
from(sourceSets.test)
}
artifacts.add("testClasses", testJar)
Some of the other answers caused errors one way or another - Gradle did not detect test classes from other projects or Eclipse project had invalid dependencies when imported. If anyone has the same problem, I suggest going with:
testCompile project(':core')
testCompile files(project(':core').sourceSets.test.output.classesDir)
The first line forces the Eclipse to link the other project as dependency, so all sources are included and up to date. The second allows Gradle to actually see the sources, while not causing any invalid dependency errors like testCompile project(':core').sourceSets.test.output does.
in project B:
dependencies {
testCompile project(':projectA').sourceSets.test.output
}
Seems to work in 1.7-rc-2