Added support for serializing/deserializing WrappedServerPing to JSON.

ProtocolLib/.classpath

@@ -12,7 +12,7 @@
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>
-	<classpathentry kind="src" path="src/test/resources"/>
+	<classpathentry including="**/*.java" kind="src" path="src/test/resources"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/4"/>
 	<classpathentry excluding="**" kind="src" output="target/classes" path="src/main/resources">
 		<attributes>

ProtocolLib/.settings/org.eclipse.core.resources.prefs

@@ -2,4 +2,5 @@ eclipse.preferences.version=1
 encoding//src/main/java=cp1252
 encoding//src/main/resources=cp1252
 encoding//src/test/java=cp1252
+encoding//src/test/resources=cp1252
 encoding/<project>=cp1252

ProtocolLib/src/main/java/com/comphenix/protocol/reflect/accessors/Accessors.java

@@ -4,7 +4,6 @@ import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.util.List;
-
 import com.comphenix.protocol.reflect.ExactReflection;
 import com.comphenix.protocol.reflect.FuzzyReflection;
 import com.google.common.base.Joiner;
@@ -106,6 +105,50 @@ public final class Accessors {
 		field.setAccessible(true);
 		return new DefaultFieldAccessor(field);
 	}
+	
+	/**
+	 * Retrieve a field accessor that will cache the content of the field.
+	 * <p>
+	 * Note that we don't check if the underlying field has changed after the value has been cached, 
+	 * so it's best to use this on final fields.
+	 * @param inner - the accessor.
+	 * @return A cached field accessor.
+	 */
+	public static FieldAccessor getCached(final FieldAccessor inner) {
+		return new FieldAccessor() {
+			private final Object EMPTY = new Object();
+			private volatile Object value = EMPTY;
+			
+			@Override
+			public void set(Object instance, Object value) {
+				inner.set(instance, value);
+				update(value);
+			}
+						
+			@Override
+			public Object get(Object instance) {
+				Object cache = value;
+				
+				if (cache != EMPTY)
+					return cache;
+				return update(inner.get(instance));
+			}
+			
+			/**
+			 * Update the cached value.
+			 * @param value - the value to cache.
+			 * @return The cached value.
+			 */
+			private Object update(Object value) {
+				return this.value = value;
+			}
+			
+			@Override
+			public Field getField() {
+				return inner.getField();
+			}
+		};
+	}
 
 	/**
 	 * Retrieve a field accessor where the write operation is synchronized on the current field value.

ProtocolLib/src/main/java/com/comphenix/protocol/utility/MinecraftReflection.java

@@ -78,6 +78,7 @@ import com.google.common.base.Joiner;
 public class MinecraftReflection {
 	public static final ReportType REPORT_CANNOT_FIND_MCPC_REMAPPER = new ReportType("Cannot find MCPC remapper.");
 	public static final ReportType REPORT_CANNOT_LOAD_CPC_REMAPPER = new ReportType("Unable to load MCPC remapper.");
+	public static final ReportType REPORT_NON_CRAFTBUKKIT_LIBRARY_PACKAGE = new ReportType("Cannot find standard Minecraft library location. Assuming MCPC.");
 	
 	/**
 	 * Regular expression that matches a Minecraft object.
@@ -101,7 +102,12 @@ public class MinecraftReflection {
 	 * The package name of all the classes that belongs to the native code in Minecraft.
 	 */
 	private static String MINECRAFT_PREFIX_PACKAGE = "net.minecraft.server";
-
+	
+	/**
+	 * The package with all the library classes.
+	 */
+	private static String MINECRAFT_LIBRARY_PACKAGE = "net.minecraft.util";
+	
 	/**
 	 * Represents a regular expression that will match the version string in a package:
 	 *    org.bukkit.craftbukkit.v1_6_R2      ->      v1_6_R2
@@ -114,6 +120,7 @@ public class MinecraftReflection {
 	// Package private for the purpose of unit testing
 	static CachedPackage minecraftPackage;
 	static CachedPackage craftbukkitPackage;
+	static CachedPackage libraryPackage;
 	
 	// org.bukkit.craftbukkit
 	private static Constructor<?> craftNMSConstructor;
@@ -199,6 +206,9 @@ public class MinecraftReflection {
 				// Libigot patch
 				handleLibigot();
 				
+				// Minecraft library package
+				handleLibraryPackage();
+				
 				// Next, do the same for CraftEntity.getHandle() in order to get the correct Minecraft package
 				Class<?> craftEntity = getCraftEntityClass();
 				Method getHandle = craftEntity.getMethod("getHandle");
@@ -244,7 +254,30 @@ public class MinecraftReflection {
 			throw new IllegalStateException("Could not find Bukkit. Is it running?");
 		}
 	}
+
+	/**
+	 * Retrieve the Minecraft library package string.
+	 * @return The library package.
+	 */
+	private static String getMinecraftLibraryPackage() {
+		getMinecraftPackage();
+		return MINECRAFT_LIBRARY_PACKAGE;
+	}
 	
+	private static void handleLibraryPackage() {
+		try {
+			MINECRAFT_LIBRARY_PACKAGE = "net.minecraft.util";
+			// Try loading Google GSON
+			getClassSource().loadClass(CachedPackage.combine(MINECRAFT_LIBRARY_PACKAGE, "com.google.gson.Gson"));
+			
+		} catch (Exception e) {
+			// Assume it's MCPC
+			MINECRAFT_LIBRARY_PACKAGE = "";
+			ProtocolLibrary.getErrorReporter().reportWarning(MinecraftReflection.class, 
+				Report.newBuilder(REPORT_NON_CRAFTBUKKIT_LIBRARY_PACKAGE));
+		}
+	}
+
 	/**
 	 * Retrieve the package version of the underlying CraftBukkit server.
 	 * @return The package version, or NULL if not applicable (before 1.4.6).
@@ -1552,6 +1585,20 @@ public class MinecraftReflection {
 		}
 	}
 	
+	/**
+	 * Retrieve the google.gson.Gson class used by Minecraft.
+	 * @return The GSON class.
+	 */
+	public static Class<?> getMinecraftGsonClass() {
+		try {
+			return getMinecraftLibraryClass("com.google.gson.Gson");
+		} catch (RuntimeException e) {
+			Class<?> match = FuzzyReflection.fromClass(PacketType.Status.Server.OUT_SERVER_INFO.getPacketClass()).
+					getFieldByType(".*\\.google\\.gson\\.Gson").getType();
+			return setMinecraftLibraryClass("com.google.gson.Gson", match);
+		}
+	}
+	
 	/**
 	 * Determine if a given method retrieved by ASM is a constructor.
 	 * @param name - the name of the method.
@@ -1766,6 +1813,31 @@ public class MinecraftReflection {
 		return minecraftPackage.getPackageClass(className);
 	}
 	
+	/**
+	 * Retrieve the class object of a specific Minecraft library class.
+	 * @param className - the specific library Minecraft class.
+	 * @return Class object.
+	 * @throws RuntimeException If we are unable to find the given class.
+	 */
+	public static Class<?> getMinecraftLibraryClass(String className) {
+		if (libraryPackage == null)
+			libraryPackage = new CachedPackage(getMinecraftLibraryPackage(), getClassSource());
+		return libraryPackage.getPackageClass(className);
+	}
+	
+	/**
+	 * Set the class object for the specific library class.
+	 * @param className - name of the Minecraft library class.
+	 * @param clazz - the new class object.
+	 * @return The provided clazz object.
+	 */
+	private static Class<?> setMinecraftLibraryClass(String className, Class<?> clazz) {
+		if (libraryPackage == null)
+			libraryPackage = new CachedPackage(getMinecraftLibraryPackage(), getClassSource());
+		libraryPackage.setPackageClass(className, clazz);
+		return clazz;
+	}
+	
 	/**
 	 * Set the class object for the specific Minecraft class.
 	 * @param className - name of the Minecraft class.

ProtocolLib/src/main/java/com/comphenix/protocol/wrappers/WrappedServerPing.java

@@ -20,11 +20,13 @@ import net.minecraft.util.io.netty.buffer.Unpooled;
 import net.minecraft.util.io.netty.handler.codec.base64.Base64;
 import net.minecraft.util.io.netty.util.IllegalReferenceCountException;
 
+import com.comphenix.protocol.PacketType;
 import com.comphenix.protocol.injector.BukkitUnwrapper;
 import com.comphenix.protocol.reflect.EquivalentConverter;
 import com.comphenix.protocol.reflect.accessors.Accessors;
 import com.comphenix.protocol.reflect.accessors.ConstructorAccessor;
 import com.comphenix.protocol.reflect.accessors.FieldAccessor;
+import com.comphenix.protocol.reflect.accessors.MethodAccessor;
 import com.comphenix.protocol.utility.MinecraftReflection;
 import com.comphenix.protocol.utility.MinecraftVersion;
 import com.google.common.base.Charsets;
@@ -59,6 +61,14 @@ public class WrappedServerPing extends AbstractWrapper {
 	private static FieldAccessor PLAYERS_MAXIMUM = PLAYERS_INTS[0];
 	private static FieldAccessor PLAYERS_ONLINE = PLAYERS_INTS[1];
 	
+	// Server ping serialization
+	private static Class<?> GSON_CLASS = MinecraftReflection.getMinecraftGsonClass();
+	private static MethodAccessor GSON_TO_JSON = Accessors.getMethodAccessor(GSON_CLASS, "toJson", Object.class);
+	private static MethodAccessor GSON_FROM_JSON = Accessors.getMethodAccessor(GSON_CLASS, "fromJson", String.class, Class.class);
+	private static FieldAccessor PING_GSON = Accessors.getCached(Accessors.getFieldAccessor(
+		PacketType.Status.Server.OUT_SERVER_INFO.getPacketClass(), GSON_CLASS, true
+	));
+	
 	// Server data fields
 	private static Class<?> VERSION_CLASS = MinecraftReflection.getServerPingServerDataClass();
 	private static ConstructorAccessor VERSION_CONSTRUCTOR = Accessors.getConstructorAccessor(VERSION_CLASS, String.class, int.class);
@@ -117,6 +127,15 @@ public class WrappedServerPing extends AbstractWrapper {
 		return new WrappedServerPing(handle);
 	}
 	
+	/**
+	 * Construct a wrapper server ping from an encoded JSON string.
+	 * @param json - the JSON string.
+	 * @return The wrapped server ping.
+	 */
+	public static WrappedServerPing fromJson(String json) {
+		return fromHandle(GSON_FROM_JSON.invoke(PING_GSON.get(null), json, SERVER_PING));
+	}
+	
 	/**
 	 * Retrieve the message of the day.
 	 * @return The messge of the day.
@@ -329,6 +348,14 @@ public class WrappedServerPing extends AbstractWrapper {
 		return copy;
 	}
 	
+	/**
+	 * Retrieve the underlying JSON representation of this server ping.
+	 * @return The JSON representation.
+	 */
+	public String toJson() {
+		return (String) GSON_TO_JSON.invoke(PING_GSON.get(null), handle);
+	}
+	
 	/**
 	 * Represents a compressed favicon.
 	 * @author Kristian