compile ('de.test:project1:1.0.0')

plugins {
    id 'java'
    id 'maven-publish'
    }
dependencies {
//    compile project(':project1')
    compile ('de.test:project1:1.0.0')
    testCompile 'junit:junit:4.12'
}
sourceCompatibility = JavaVersion.VERSION_1_8
targetCompatibility = JavaVersion.VERSION_1_8
publishing {
    publications {
        publish(MavenPublication) {
            groupId 'de.test'
            artifactId 'project2'
            version '1.0.0'
            from components.java
        }
    }
}

rootProject.name = 'project1'

allprojects {
   group 'de.test'
   version '1.0.0'
}