how to copy the dependencies libraries JARs in gradle

Add:

build.dependsOn(copyToLib)

When gradle build runs, Gradle builds tasks and whatever tasks depend on it (declared by dependsOn). Without setting build.dependsOn(copyToLib), Gradle will not associate the copy task with the build task.

So:

apply plugin: 'java'
apply plugin: 'application'

manifest.mainAttributes('Main-Class': 'com.test.HelloWorld')

repositories {
    mavenCentral()
}

dependencies {
    compile (
        'commons-codec:commons-codec:1.6',
        'commons-logging:commons-logging:1.1.1',
        'org.apache.httpcomponents:httpclient:4.2.1',
        'org.apache.httpcomponents:httpclient:4.2.1',
        'org.apache.httpcomponents:httpcore:4.2.1',
        'org.apache.httpcomponents:httpmime:4.2.1',
        'ch.qos.logback:logback-classic:1.0.6',
        'ch.qos.logback:logback-core:1.0.6',
        'org.slf4j:slf4j-api:1.6.0',
        'junit:junit:4.+'
    )
}

task copyToLib(type: Copy) {
    into "${buildDir}/output/libs"
    from configurations.runtime
}

build.dependsOn(copyToLib)