如何使用本地 JUnit Jar 从 Gradle 而不是 Maven 中央？

Question

I'm trying to run my JUnit tests in an environment where I have no inte.net access but I have SSH access and can sync my local files etc.

I thought I could just add my JUnit jar to the project but that doesn't seem to work (and it doesn't seem to get downloaded to my Maven cache).

Ideally I could do this on my dev machine with Inte.net access - to compile everything and just sync it over

gradle assemble testClasses

Simple example

Start with this https://github.com/spring-guides/gs-rest-service Edit build.gradle to add lines to grab Jars locally

Add JUnit jar to "libs" folder ie mkdir libs; cd libs; wget https://repo.maven.apache.org/maven2/org/junit/jupiter/junit-jupiter-engine/5.7.2/junit-jupiter-engine-5.7.2.jar

plugins {
    id 'org.springframework.boot' version '2.5.2'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    mavenCentral()
}

dependencies {
    compile fileTree(dir: 'libs', include: '*.jar')
    testCompile fileTree(dir: 'libs', include: '*.jar')
    implementation 'org.springframework.boot:spring-boot-starter-web'
    testImplementation('org.springframework.boot:spring-boot-starter-test')
}

test {
    useJUnitPlatform()
}

But it doesn't look for JUnit jar in "libs" - it's still trying to grab from Maven Central:

gradle clean test

Task:test FAILED

FAILURE: Build failed with an exception.

• What went wrong: Execution failed for task ':test'.

Could not download junit-jupiter-engine-5.7.2.jar (org.junit.jupiter:junit-jupiter-engine:5.7.2) Could not get resource 'https://repo.maven.apache.org/maven2/org/junit/jupiter/junit-jupiter-engine/5.7.2/junit-jupiter-engine-5.7.2.jar'. > Could not GET 'https://repo.maven.apache.org/maven2/org/junit/jupiter/junit-jupiter-engine/5.7.2/junit-jupiter-engine-5.7.2.jar'. > repo.maven.apache.org: Temporary failure in name resolution

• Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

• Get more help at https://help.gradle.org

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0. Use '--warning-mode all' to show the individual deprecation warnings. See https://docs.gradle.org/6.8.3/userguide/command_line_interface.html#sec:command_line_warnings

BUILD FAILED in 4s 4 actionable tasks: 4 executed

UPDATE

What does Gradle expect as the folder format?

Here's what I tried

Changed my settings.gradle to this

pluginManagement {
    repositories {
        maven {
            url './libs'
        }
    }
}

Copying all the jars to my libs folder

find. -name " spring 2.5.2*jar" | xargs cp -t ~/complete/libs/

and for fun copied the whole folder cp -rf ~/.gradle/caches/modules-2/files-2.1/ ~/complete/libs/

But still it can't find the Spring plugin?

My libs folder now looks like this

$ ls libs
6.8.3                       org.assertj
ch.qos.logback                  org.codehaus.groovy
com.datastax.oss                org.eclipse.ee4j
com.fasterxml                   org.eclipse.jetty
com.fasterxml.jackson               org.glassfish.jersey
com.fasterxml.jackson.core          org.hamcrest
com.fasterxml.jackson.datatype          org.infinispan
com.fasterxml.jackson.module            org.jboss
com.google.code.findbugs            org.jetbrains.kotlin
com.jayway.jsonpath             org.jetbrains.kotlinx
com.oracle.database.jdbc            org.junit
com.sun.activation              org.junit.jupiter
com.vaadin.external.google          org.junit.platform
commons-codec                   org.mockito
commons-logging                 org.objenesis
dependency-management-plugin-1.0.11.RELEASE.jar org.opentest4j
files-2.1                   org.ow2
io.dropwizard.metrics               org.ow2.asm
io.micrometer                   org.skyscreamer
io.netty                    org.slf4j
io.projectreactor               org.sonatype.oss
io.prometheus                   org.springframework
io.r2dbc                    org.springframework.boot
io.rsocket                  org.springframework.data
io.spring.dependency-management         org.springframework.integration
io.spring.gradle                org.springframework.security
jakarta.activation              org.springframework.session
jakarta.annotation              org.tomlj
jakarta.xml.bind                org.xmlunit
jars-8                      org.yaml
journal-1                   spring-boot-2.5.2.jar
junit-jupiter-engine-5.7.2.jar          spring-boot-autoconfigure-2.5.2.jar
modules-2                   spring-boot-buildpack-platform-2.5.2.jar
net.bytebuddy                   spring-boot-gradle-plugin-2.5.2.jar
net.java.dev.jna                spring-boot-loader-tools-2.5.2.jar
net.minidev                 spring-boot-starter-2.5.2.jar
org.antlr                   spring-boot-starter-json-2.5.2.jar
org.apache                  spring-boot-starter-logging-2.5.2.jar
org.apache.commons              spring-boot-starter-test-2.5.2.jar
org.apache.httpcomponents           spring-boot-starter-tomcat-2.5.2.jar
org.apache.logging              spring-boot-starter-web-2.5.2.jar
org.apache.logging.log4j            spring-boot-test-2.5.2.jar
org.apache.tomcat.embed             spring-boot-test-autoconfigure-2.5.2.jar
org.apiguardian                 transforms-3

$ gradle test

FAILURE: Build failed with an exception.

• Where: Build file '/Users/dennch3/tsmec/modules/e2etests/complete/build.gradle' line: 2

• What went wrong: Plugin [id: 'org.springframework.boot', version: '2.5.2'] was not found in any of the following sources:

• Gradle Core Plugins (plugin is not in 'org.gradle' namespace)
• Plugin Repositories (could not resolve plugin artifact 'org.springframework.boot:org.springframework.boot.gradle.plugin:2.5.2') Searched in the following repositories: maven(file:~/complete/libs/)

Answer 1

the issue for you is not junit, to run gradle you need access to a maven repository for dependencies and gradle plugin repository (you have spring boot)

you selected mavencentral(), but with out access to inte.net this won't work, you should get access to local repositories for maven and Gradle-plugins.

if your libs already had the spring jars, then remove the spring related dependencies (lines 3,4)

also change from testCompile to testImplementation (line2)

PS - you may also need for the plugins to add local repository see https://docs.gradle.org/current/userguide/plugins.html#sec:custom_plugin_repositories