Разработка приложения на Android студии с использованием Gradle. Я добавил эту зависимость к нему:

compile 'com.android.support:appcompat-v7:23.0.1'
compile 'com.squareup.retrofit:retrofit:1.9.0'
compile 'com.google.code.gson:gson:2.3.1'

но это говорит:

Error:A problem occurred configuring project ':app'.
> Could not download gson.jar (com.google.code.gson:gson:2.3.1)
   > Could not get resource 'https://jcenter.bintray.com/com/google/code/gson/gson/2.3.1/gson-2.3.1.jar'.
      > Could not GET 'https://jcenter.bintray.com/com/google/code/gson/gson/2.3.1/gson-2.3.1.jar'.
         > Connection to https://jcenter.bintray.com refused

Полный исходный код для моих файлов build.gradle

Проект:

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:1.3.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

Приложение:

apply plugin: 'com.android.application'


android {
    compileSdkVersion 23
    buildToolsVersion "23.0.1"

    defaultConfig {
        applicationId "domain.myapplication"
        minSdkVersion 11
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:23.0.1'
    compile 'com.squareup.retrofit:retrofit:1.9.0'
    compile 'com.google.code.gson:gson:2.3.1'

}