Include volley as jar dependency in your pom.xml or build.gradle.

1. Clone the repo
2. mvn clean install

It pushes the volley jar in your local maven repository. Next, you can include the dependency in your projects using maven or gradle.

Dependency for pom.xml:

<dependency>
  <groupId>com.google.volley</groupId>
  <artifactId>volley</artifactId>
  <version>1.0.0-SNAPSHOT</version>
  <packaging>jar</packaging>
</dependency>

Dependency for build.gradle:

repositories {
    mavenCentral()
    mavenLocal()
}

dependencies {
  compile 'com.google.volley:volley:1.0.0-SNAPSHOT'
}