Adds error-prone to check java code

build.gradle

@@ -1,5 +1,16 @@
 import org.gradle.internal.os.OperatingSystem
 
+buildscript {
+    repositories {
+        maven {
+            url "https://plugins.gradle.org/m2/"
+        }
+    }
+    dependencies {
+        classpath 'net.ltgt.gradle:gradle-errorprone-plugin:0.0.8'
+    }
+}
+
 // Determine what repo to publish to. Default is development. Valid options are development, beta, stable, and release
 if (!hasProperty('repo')) {
     allprojects {

java/java.gradle

@@ -1,6 +1,15 @@
 import org.gradle.internal.os.OperatingSystem
 
 apply plugin: 'java'
+apply plugin: 'net.ltgt.errorprone'
+
+repositories {
+    mavenCentral()
+}
+
+configurations.errorprone {
+    resolutionStrategy.force 'com.google.errorprone:error_prone_core:2.0.9'
+}
 
 def generatedJNIHeaderLoc = '../build/include'
 

java/src/edu/wpi/first/wpilibj/networktables/NetworkTableKeyNotDefined.java

@@ -10,6 +10,7 @@ import edu.wpi.first.wpilibj.tables.TableKeyNotDefinedException;
  * @author Mitchell
  *
  */
+@Deprecated
 public class NetworkTableKeyNotDefined extends TableKeyNotDefinedException {
 
 	/**

java/src/edu/wpi/first/wpilibj/networktables2/type/ArrayData.java

@@ -3,6 +3,7 @@ package edu.wpi.first.wpilibj.networktables2.type;
 /**
  * @deprecated Use ArrayList instead.
  */
+@Deprecated
 public class ArrayData {
   private Object[] data = new Object[0];
 

java/src/edu/wpi/first/wpilibj/networktables2/type/BooleanArray.java

@@ -3,6 +3,7 @@ package edu.wpi.first.wpilibj.networktables2.type;
 /**
  * @deprecated Use {@literal ArrayList<Boolean>} instead.
  */
+@Deprecated
 public class BooleanArray extends ArrayData {
   public boolean get(int index) {
     return ((Boolean)getAsObject(index)).booleanValue();

java/src/edu/wpi/first/wpilibj/networktables2/type/NumberArray.java

@@ -3,6 +3,7 @@ package edu.wpi.first.wpilibj.networktables2.type;
 /**
  * @deprecated Use {@literal ArrayList<Double>} instead.
  */
+@Deprecated
 public class NumberArray extends ArrayData {
   public double get(int index) {
     return ((Double)getAsObject(index)).doubleValue();

java/src/edu/wpi/first/wpilibj/networktables2/type/StringArray.java

@@ -3,6 +3,7 @@ package edu.wpi.first.wpilibj.networktables2.type;
 /**
  * @deprecated Use {@literal ArrayList<String>} instead.
  */
+@Deprecated
 public class StringArray extends ArrayData {
   public String get(int index) {
     return ((String)getAsObject(index));