Localization is done, see the format of the en_US.xml file for how to specify your own custom localization files. Feel free to contribute your translations to the GitHub as appropriate.

ee3_common/ee3/common/EquivalentExchange3.java

@@ -23,6 +23,7 @@ import ee3.common.core.handlers.AddonHandler;
 import ee3.common.core.handlers.ConfigurationHandler;
 import ee3.common.core.handlers.EntityLivingHandler;
 import ee3.common.core.handlers.ItemPickupHandler;
+import ee3.common.core.handlers.LocalizationHandler;
 import ee3.common.core.handlers.PacketHandler;
 import ee3.common.core.handlers.PlayerDestroyItemHandler;
 import ee3.common.core.handlers.VersionCheckTickHandler;
@@ -72,6 +73,9 @@ public class EquivalentExchange3 {
     @Init
     public void load(FMLInitializationEvent event) {
     	
+    	// Load the localization files into the LanguageRegistry
+    	LocalizationHandler.loadLanguages();
+    	
         // Initialize the custom item rarity types
         proxy.initCustomRarityTypes();
 

ee3_common/ee3/common/block/ModBlocks.java

@@ -25,10 +25,6 @@ public class ModBlocks {
 		redWaterStill = new BlockRedWaterStill(BlockIds.RED_WATER_STILL, Material.water);
 		redWaterFlowing = new BlockRedWaterFlowing(BlockIds.RED_WATER_STILL - 1, Material.water);
 		
-		LanguageRegistry.addName(calcinator, "Calcinator");
-		LanguageRegistry.addName(redWaterStill, "Red Water (Still)");
-		LanguageRegistry.addName(redWaterFlowing, "Red Water (Flowing)");
-		
 		GameRegistry.registerBlock(calcinator);
 		GameRegistry.registerBlock(redWaterStill);
 		GameRegistry.registerBlock(redWaterFlowing);

ee3_common/ee3/common/core/handlers/LocalizationHandler.java

@@ -1,5 +1,70 @@
 package ee3.common.core.handlers;
 
-public class LocalizationHandler {
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Iterator;
+import java.util.Properties;
+import cpw.mods.fml.common.registry.LanguageRegistry;
+import ee3.common.core.helper.LocalizationHelper;
+import ee3.common.lib.Localizations;
 
+/**
+ * LocalizationHandler
+ * 
+ * Loads in all specified localizations for the mod
+ * 
+ * @author pahimar
+ * @license Lesser GNU Public License v3 (http://www.gnu.org/licenses/lgpl.html)
+ * 
+ */
+public class LocalizationHandler {
+	
+	/***
+	 * Loads in all the localization files from the Localizations library class
+	 */
+	public static void loadLanguages() {
+		InputStream languageStream = null;
+		Properties languageMappings = new Properties();
+		Iterator<String> keyIter = null;
+		String currentKey, currentLang;
+		
+		try {
+			// For every file specified in the Localization library class, load them into the Language Registry
+			for (String localizationFile : Localizations.localeFiles) {
+				languageStream = LocalizationHandler.class.getResourceAsStream(localizationFile);
+				
+				// If this file is a XML file, load it from XML
+				if (LocalizationHelper.isXMLLanguageFile(localizationFile)) {
+					languageMappings.loadFromXML(languageStream);
+				}
+				// Otherwise, load it like any other Java Properties file
+				else {
+					languageMappings.load(languageStream);
+				}
+				
+				// Read the locale from the file name of the localization file
+				currentLang = LocalizationHelper.getLocaleFromFileName(localizationFile);
+				
+				// For every key in the localization file, add its key:value pair to the Language Registry for the given locale
+				keyIter = (Iterator<String>)languageMappings.keys();
+				while (keyIter.hasNext()) {
+					currentKey = keyIter.next();
+					LanguageRegistry.instance().addStringLocalization(currentKey, currentLang, languageMappings.getProperty(currentKey));
+				}
+			}
+			
+		} catch (Exception e) {
+			e.printStackTrace(System.err);
+		} finally {
+			try {
+				if (languageStream != null) {
+					languageStream.close();
+				}
+			} catch (IOException ex) {
+				ex.printStackTrace(System.err);
+			}
+		}
+		
+	}
+	
 }

ee3_common/ee3/common/core/helper/LocalizationHelper.java

@@ -0,0 +1,73 @@
+package ee3.common.core.helper;
+
+import java.util.HashMap;
+import java.util.Properties;
+import cpw.mods.fml.common.registry.LanguageRegistry;
+import cpw.mods.fml.relauncher.ReflectionHelper;
+import net.minecraft.src.StringTranslate;
+import ee3.common.core.handlers.LocalizationHandler;
+
+/**
+ * LocalizationHelper
+ * 
+ * Helper class for looking up localized strings in the Language Registry
+ * 
+ * @author pahimar
+ * @license Lesser GNU Public License v3 (http://www.gnu.org/licenses/lgpl.html)
+ * 
+ */
+public class LocalizationHelper {
+
+	// The language data field name for localization data in the Language Registry 
+	private static final String LANGUAGE_REGISTRY_LANGUAGE_DATA_FIELD = "modLanguageData";
+	
+	/***
+	 * Returns the localized version of the text represented by key for the current language from the Language Registry
+	 * @param key The key that represents the text we are attempting to localize
+	 * @return The localized string for the specified key for the current language, null if no localized version of the key exists in the Language Registry
+	 */
+	public static String localize(String key) {
+		return localize(StringTranslate.getInstance().getCurrentLanguage(), key);
+	}
+
+	/***
+	 * Returns the localized version of the text represented by key for the specified language from the Language Registry
+	 * @param language The language for which to search for the localized version of the key
+	 * @param key The key that represents the text we are attempting to localize
+	 * @return The localized string for the specified key for the specified language, null if no localized version of the key exists in the Language Registry
+	 */
+	public static String localize(String language, String key) {
+		String localizedValue = "";
+		HashMap<String,Properties> modLanguageData = null;
+		Properties languageMapping = null;
+		
+		try {
+			modLanguageData = ReflectionHelper.getPrivateValue(cpw.mods.fml.common.registry.LanguageRegistry.class, LanguageRegistry.instance(), LANGUAGE_REGISTRY_LANGUAGE_DATA_FIELD);
+			languageMapping = modLanguageData.get(language);
+			localizedValue = languageMapping.getProperty(key);
+		} catch (Exception e) {
+			e.printStackTrace(System.err);
+		}
+		
+		return localizedValue;
+	}
+	
+	/***
+	 * Simple test to determine if a specified file name represents a XML file or not
+	 * @param fileName String representing the file name of the file in question
+	 * @return True if the file name represents a XML file, false otherwise
+	 */
+	public static boolean isXMLLanguageFile(String fileName) {
+		return fileName.endsWith(".xml");
+	}
+	
+	/***
+	 * Returns the locale from file name
+	 * @param fileName String representing the file name of the file in question
+	 * @return String representation of the locale snipped from the file name
+	 */
+	public static String getLocaleFromFileName(String fileName) {
+		return fileName.substring(fileName.lastIndexOf('/') + 1, fileName.lastIndexOf('.'));
+	}
+	
+}

ee3_common/ee3/common/item/ModItems.java

@@ -34,9 +34,6 @@ public class ModItems {
 
         miniumStone.setContainerItem(miniumStone);
         philStone.setContainerItem(philStone);
-        
-        LanguageRegistry.addName(miniumShard, "Shard of Minium");
-        LanguageRegistry.addName(miniumStone, "Minium Stone");
-        LanguageRegistry.addName(philStone, "Philosophers Stone");
+
     }
 }

ee3_common/ee3/common/lib/Localizations.java

@@ -0,0 +1,20 @@
+package ee3.common.lib;
+
+/**
+ * BlockIds
+ * 
+ * Library containing all mod language related files
+ * 
+ * @author pahimar
+ * @license Lesser GNU Public License v3 (http://www.gnu.org/licenses/lgpl.html)
+ * 
+ */
+public class Localizations {
+	
+	private static final String LANG_RESOURCE_LOCATION = "/ee3/lang/";
+	
+	public static String[] localeFiles = {
+		LANG_RESOURCE_LOCATION + "en_US.xml"
+	};
+
+}

ee3_common/ee3/common/lib/Reference.java

@@ -40,10 +40,11 @@ public class Reference {
 
     /* Texture related constants */
     public static final String SPRITE_SHEET_LOCATION = "/ee3/art/sprites/";
+    public static final String ARMOR_SHEET_LOCATION = "/ee3/art/armor/";
+    public static final String GUI_SHEET_LOCATION = "/ee3/art/gui/";
     public static final String ITEM_SPRITE_SHEET = "ee3_items.png";
     public static final String BLOCK_SPRITE_SHEET = "ee3_blocks.png";
-    public static final String GUI_SHEET_LOCATION = "/ee3/art/gui/";
-    public static final String ARMOR_SHEET_LOCATION = "/ee3/art/armor/";
+    
 
     public static final int SECOND_IN_TICKS = 20;
 

resources/ee3/lang/en_US.lang

@@ -1,5 +0,0 @@
-item.miniumShard=Minium Shard
-item.miniumStone=Minium Stone
-item.philosophersStone=Philosophers Stone
-tile.redWaterStill=Red Water
-tile.redWaterFlowing=Red Water

resources/ee3/lang/en_US.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">
+<properties version="1.0">
+	<comment>English (US) Localization File</comment>
+	<entry key="item.miniumShard.name">Shard of Minium</entry>
+	<entry key="item.miniumStone.name">Minium Stone</entry>
+	<entry key="item.philStone.name">Philosophers Stone</entry>
+	<entry key="tile.redWaterStill.name">Red Water (Still)</entry>
+	<entry key="tile.redWaterFlowing.name">Red Water (Flowing)</entry>
+	<entry key="tile.calcinator.name">Calcinator</entry>
+	<entry key="version.uninitialized">Uninitialized</entry>
+	<entry key="version.current">Current</entry>
+	<entry key="version.outdated">Outdated</entry>
+	<entry key="version.connection_error">Connection Error</entry>
+</properties>