[BUILD] update to gradle build tools 3.0.1

build.gradle

@@ -1,9 +1,10 @@
 buildscript {
     repositories {
         jcenter()
+        google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.1.3'
+        classpath 'com.android.tools.build:gradle:3.0.1'
     }
 }
 
@@ -21,6 +22,13 @@ android {
         targetSdkVersion project.hasProperty("defaultTargetSdkVersion") ? defaultTargetSdkVersion : 23
     }
 
+    buildTypes {
+        release {
+            minifyEnabled true
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard_libvorbis-libogg.cfg'
+        }
+    }
+
     lintOptions { abortOnError false }
 
     sourceSets {

proguard_libvorbis-libogg.cfg

@@ -11,6 +11,12 @@
 -keep public class * extends android.content.BroadcastReceiver
 -keep public class * extends android.content.ContentProvider
 -keep public class com.android.vending.licensing.ILicensingService
+-keep class org.xiph.vorbis.decoder.VorbisDecoder.** { *; }
+-keep class org.xiph.vorbis.encoder.VorbisEncoder.** { *; }
+-keep class org.xiph.vorbis.encoder.EncodeFeed.** { *; }
+-keep , includedescriptorclasses class org.xiph.vorbis.stream.VorbisInfo.** { *; }
+-keep , includedescriptorclasses class org.xiph.vorbis.stream.VorbisFileInputStream.** { *; }
+-keep , includedescriptorclasses class org.xiph.vorbis.stream.VorbisFileOutputStream.** { *; }
 
 -keepclasseswithmembernames class * {
     native <methods>;

src/org/xiph/vorbis/player/VorbisPlayer.java

@@ -33,7 +33,7 @@ public class VorbisPlayer implements Runnable {
     /**
      * Playing state which can either be stopped, playing, or reading the header before playing
      */
-    private static enum PlayerState {
+    private enum PlayerState {
         PLAYING, STOPPED, READING_HEADER, BUFFERING
     }
 
@@ -70,7 +70,7 @@ public class VorbisPlayer implements Runnable {
     /**
      * Current state of the vorbis player
      */
-    private AtomicReference<PlayerState> currentState = new AtomicReference<PlayerState>(PlayerState.STOPPED);
+    private AtomicReference<PlayerState> currentState = new AtomicReference<>(PlayerState.STOPPED);
 
     /**
      * Custom class to easily decode from a file and write to an {@link AudioTrack}