在gradle中使用Firebase数据库

Caused by: java.lang.NoSuchMethodError: org.json.JSONObject.<init>(Ljava/lang/String;)V
    at com.google.firebase.auth.FirebaseCredentials$CertCredential.<init>(FirebaseCredentials.java:273)
    at com.google.firebase.auth.FirebaseCredentials.fromCertificate(FirebaseCredentials.java:156)
    at com.google.firebase.auth.FirebaseCredentials.fromCertificate(FirebaseCredentials.java:130)
    at com.google.firebase.auth.FirebaseCredentials$fromCertificate.call(Unknown Source)
    at eu.long1.jwnotes.gradleplugins.UploadTask.action(UploadTask.groovy:31)

任务如下:

class UploadTask extends DefaultTask {

    String message = "Huray!"

    @TaskAction
    def action() {

        String a = "private-key"

        FirebaseOptions options = new FirebaseOptions.Builder()
                .setCredential(FirebaseCredentials.fromCertificate(new ByteArrayInputStream(a.getBytes("UTF-8"))))
                .setDatabaseUrl("https://jwnotes.firebaseio.com/")
                .build()

        FirebaseApp.initializeApp(options)


        FirebaseDatabase.getInstance().getReference().child("alfa-gradle").setValue(message)
    }
}

当我试图申请运行任务时,出现了错误。

更新

这是我的插件gradle文件:

plugins {
    id 'groovy'
    id 'maven'
}

group 'eu.long1.jwnotes.gradleplugins'
version '1.0-SNAPSHOT'

repositories {
    mavenCentral()
}

dependencies {
    compile gradleApi()
    compile localGroovy()
}

dependencies {
    compile 'com.google.firebase:firebase-admin:5.3.1'
    compile 'org.json:json:20160810'

}

sourceCompatibility = 1.8

jar {
    into('lib') {
        from 'lib'
    }
}