[Bleeding] Cleaned up unsafe casts. Addresses BUKKIT-844

Removed internal collection leaks from PluginDescriptionFile
BREAKING: PluginDescriptionFile.getAuthors() now returns List instead of
ArrayList

Various places with unsafe generics, notably List<Object> getList() in
Configurations are now referenced as <?>. This is nonbreaking, but
sourcecode will need to be revised when compiled.

13 files changed, 165 insertions, 174 deletions

diff --git a/src/main/java/org/bukkit/command/PluginCommandYamlParser.java b/src/main/java/org/bukkit/command/PluginCommandYamlParser.java
index e7feea49..2e6fedf1 100644
--- a/src/main/java/org/bukkit/command/PluginCommandYamlParser.java
+++ b/src/main/java/org/bukkit/command/PluginCommandYamlParser.java
@@ -9,58 +9,54 @@ import org.bukkit.plugin.Plugin;
 
 public class PluginCommandYamlParser {
 
-    @SuppressWarnings("unchecked")
     public static List<Command> parse(Plugin plugin) {
         List<Command> pluginCmds = new ArrayList<Command>();
-        Object object = plugin.getDescription().getCommands();
 
-        if (object == null) {
+        Map<String, Map<String, Object>> map = plugin.getDescription().getCommands();
+
+        if (map == null) {
             return pluginCmds;
         }
 
-        Map<String, Map<String, Object>> map = (Map<String, Map<String, Object>>) object;
-
-        if (map != null) {
-            for (Entry<String, Map<String, Object>> entry : map.entrySet()) {
-                Command newCmd = new PluginCommand(entry.getKey(), plugin);
-                Object description = entry.getValue().get("description");
-                Object usage = entry.getValue().get("usage");
-                Object aliases = entry.getValue().get("aliases");
-                Object permission = entry.getValue().get("permission");
-                Object permissionMessage = entry.getValue().get("permission-message");
+        for (Entry<String, Map<String, Object>> entry : map.entrySet()) {
+            Command newCmd = new PluginCommand(entry.getKey(), plugin);
+            Object description = entry.getValue().get("description");
+            Object usage = entry.getValue().get("usage");
+            Object aliases = entry.getValue().get("aliases");
+            Object permission = entry.getValue().get("permission");
+            Object permissionMessage = entry.getValue().get("permission-message");
 
-                if (description != null) {
-                    newCmd.setDescription(description.toString());
-                }
+            if (description != null) {
+                newCmd.setDescription(description.toString());
+            }
 
-                if (usage != null) {
-                    newCmd.setUsage(usage.toString());
-                }
+            if (usage != null) {
+                newCmd.setUsage(usage.toString());
+            }
 
-                if (aliases != null) {
-                    List<String> aliasList = new ArrayList<String>();
+            if (aliases != null) {
+                List<String> aliasList = new ArrayList<String>();
 
-                    if (aliases instanceof List) {
-                        for (Object o : (List<Object>) aliases) {
-                            aliasList.add(o.toString());
-                        }
-                    } else {
-                        aliasList.add(aliases.toString());
+                if (aliases instanceof List) {
+                    for (Object o : (List<?>) aliases) {
+                        aliasList.add(o.toString());
                     }
-
-                    newCmd.setAliases(aliasList);
+                } else {
+                    aliasList.add(aliases.toString());
                 }
 
-                if (permission != null) {
-                    newCmd.setPermission(permission.toString());
-                }
+                newCmd.setAliases(aliasList);
+            }
 
-                if (permissionMessage != null) {
-                    newCmd.setPermissionMessage(permissionMessage.toString());
-                }
+            if (permission != null) {
+                newCmd.setPermission(permission.toString());
+            }
 
-                pluginCmds.add(newCmd);
+            if (permissionMessage != null) {
+                newCmd.setPermissionMessage(permissionMessage.toString());
             }
+
+            pluginCmds.add(newCmd);
         }
         return pluginCmds;
     }
diff --git a/src/main/java/org/bukkit/command/defaults/VersionCommand.java b/src/main/java/org/bukkit/command/defaults/VersionCommand.java
index 3a582359..0bd5c5af 100644
--- a/src/main/java/org/bukkit/command/defaults/VersionCommand.java
+++ b/src/main/java/org/bukkit/command/defaults/VersionCommand.java
@@ -1,7 +1,8 @@
 package org.bukkit.command.defaults;
 
-import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
+
 import org.bukkit.ChatColor;
 import org.bukkit.Bukkit;
 import org.bukkit.command.Command;
@@ -67,7 +68,7 @@ public class VersionCommand extends Command {
 
     private String getAuthors(final PluginDescriptionFile desc) {
         StringBuilder result = new StringBuilder();
-        ArrayList<String> authors = desc.getAuthors();
+        List<String> authors = desc.getAuthors();
 
         for (int i = 0; i < authors.size(); i++) {
             if (result.length() > 0) {
diff --git a/src/main/java/org/bukkit/configuration/ConfigurationSection.java b/src/main/java/org/bukkit/configuration/ConfigurationSection.java
index 7083ccc2..90d43849 100644
--- a/src/main/java/org/bukkit/configuration/ConfigurationSection.java
+++ b/src/main/java/org/bukkit/configuration/ConfigurationSection.java
@@ -174,7 +174,7 @@ public interface ConfigurationSection {
      * @param path Path to create the section at.
      * @return Newly created section
      */
-    public ConfigurationSection createSection(String path, Map<String, Object> map);
+    public ConfigurationSection createSection(String path, Map<?, ?> map);
 
     // Primitives
     /**
@@ -368,8 +368,7 @@ public interface ConfigurationSection {
      * @param path Path of the List to get.
      * @return Requested List.
      */
-    @SuppressWarnings("rawtypes")
-    public List getList(String path);
+    public List<?> getList(String path);
 
     /**
      * Gets the requested List by path, returning a default value if not found.
@@ -380,8 +379,7 @@ public interface ConfigurationSection {
      * @param path Path of the List to get.
      * @return Requested List.
      */
-    @SuppressWarnings("rawtypes")
-    public List getList(String path, List<?> def);
+    public List<?> getList(String path, List<?> def);
 
     /**
      * Checks if the specified path is a List.
@@ -544,7 +542,7 @@ public interface ConfigurationSection {
      * @param path Path of the List to get.
      * @return Requested List of Maps.
      */
-    public List<Map<String, Object>> getMapList(String path);
+    public List<Map<?, ?>> getMapList(String path);
 
     // Bukkit
     /**
diff --git a/src/main/java/org/bukkit/configuration/MemorySection.java b/src/main/java/org/bukkit/configuration/MemorySection.java
index 6d6c3f9d..549d4a13 100644
--- a/src/main/java/org/bukkit/configuration/MemorySection.java
+++ b/src/main/java/org/bukkit/configuration/MemorySection.java
@@ -261,15 +261,14 @@ public class MemorySection implements ConfigurationSection {
         }
     }
 
-    @SuppressWarnings("unchecked")
-    public ConfigurationSection createSection(String path, Map<String, Object> map) {
+    public ConfigurationSection createSection(String path, Map<?, ?> map) {
         ConfigurationSection section = createSection(path);
 
-        for (Map.Entry<String, Object> entry : map.entrySet()) {
+        for (Map.Entry<?, ?> entry : map.entrySet()) {
             if (entry.getValue() instanceof Map) {
-                section.createSection(entry.getKey(), (Map<String, Object>) entry.getValue());
+                section.createSection(entry.getKey().toString(), (Map<?, ?>) entry.getValue());
             } else {
-                section.set(entry.getKey(), entry.getValue());
+                section.set(entry.getKey().toString(), entry.getValue());
             }
         }
 
@@ -413,24 +412,22 @@ public class MemorySection implements ConfigurationSection {
     }
 
     // Java
-    @SuppressWarnings("unchecked")
-    public List<Object> getList(String path) {
+    public List<?> getList(String path) {
         if (path == null) {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
         Object def = getDefault(path);
-        return getList(path, (def instanceof List) ? (List<Object>) def : null);
+        return getList(path, (def instanceof List) ? (List<?>) def : null);
     }
 
-    @SuppressWarnings("unchecked")
-    public List<Object> getList(String path, List<?> def) {
+    public List<?> getList(String path, List<?> def) {
         if (path == null) {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
         Object val = get(path, def);
-        return (List<Object>) ((val instanceof List) ? val : def);
+        return (List<?>) ((val instanceof List) ? val : def);
     }
 
     public boolean isList(String path) {
@@ -447,7 +444,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<String>(0);
@@ -469,7 +466,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Integer>(0);
@@ -510,7 +507,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Boolean>(0);
@@ -538,7 +535,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Double>(0);
@@ -579,7 +576,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Float>(0);
@@ -620,7 +617,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Long>(0);
@@ -661,7 +658,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Byte>(0);
@@ -702,7 +699,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Character>(0);
@@ -744,7 +741,7 @@ public class MemorySection implements ConfigurationSection {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
+        List<?> list = getList(path);
 
         if (list == null) {
             return new ArrayList<Short>(0);
@@ -780,18 +777,17 @@ public class MemorySection implements ConfigurationSection {
         return result;
     }
 
-    @SuppressWarnings("unchecked")
-    public List<Map<String, Object>> getMapList(String path) {
+    public List<Map<?, ?>> getMapList(String path) {
         if (path == null) {
             throw new IllegalArgumentException("Path cannot be null");
         }
 
-        List<Object> list = getList(path);
-        List<Map<String, Object>> result = new ArrayList<Map<String, Object>>();
+        List<?> list = getList(path);
+        List<Map<?, ?>> result = new ArrayList<Map<?, ?>>();
 
         for (Object object : list) {
             if (object instanceof Map) {
-                result.add((Map<String, Object>) object);
+                result.add((Map<?, ?>) object);
             }
         }
 
diff --git a/src/main/java/org/bukkit/configuration/file/YamlConfiguration.java b/src/main/java/org/bukkit/configuration/file/YamlConfiguration.java
index 80842a70..99bfa1f8 100644
--- a/src/main/java/org/bukkit/configuration/file/YamlConfiguration.java
+++ b/src/main/java/org/bukkit/configuration/file/YamlConfiguration.java
@@ -42,16 +42,15 @@ public class YamlConfiguration extends FileConfiguration {
         return header + dump;
     }
 
-    @SuppressWarnings("unchecked")
     @Override
     public void loadFromString(String contents) throws InvalidConfigurationException {
         if (contents == null) {
             throw new IllegalArgumentException("Contents cannot be null");
         }
 
-        Map<Object, Object> input;
+        Map<?, ?> input;
         try {
-            input = (Map<Object, Object>) yaml.load(contents);
+            input = (Map<?, ?>) yaml.load(contents);
         } catch (YAMLException e) {
             throw new InvalidConfigurationException(e);
         } catch (ClassCastException e) {
@@ -68,14 +67,13 @@ public class YamlConfiguration extends FileConfiguration {
         }
     }
 
-    @SuppressWarnings("unchecked")
-    protected void convertMapsToSections(Map<Object, Object> input, ConfigurationSection section) {
-        for (Map.Entry<Object, Object> entry : input.entrySet()) {
+    protected void convertMapsToSections(Map<?, ?> input, ConfigurationSection section) {
+        for (Map.Entry<?, ?> entry : input.entrySet()) {
             String key = entry.getKey().toString();
             Object value = entry.getValue();
 
-            if (value instanceof Map<?, ?>) {
-                convertMapsToSections((Map<Object, Object>) value, section.createSection(key));
+            if (value instanceof Map) {
+                convertMapsToSections((Map<?, ?>) value, section.createSection(key));
             } else {
                 section.set(key, value);
             }
diff --git a/src/main/java/org/bukkit/configuration/file/YamlConstructor.java b/src/main/java/org/bukkit/configuration/file/YamlConstructor.java
index 7df59fb2..73ad722a 100644
--- a/src/main/java/org/bukkit/configuration/file/YamlConstructor.java
+++ b/src/main/java/org/bukkit/configuration/file/YamlConstructor.java
@@ -23,12 +23,11 @@ public class YamlConstructor extends SafeConstructor {
                 throw new YAMLException("Unexpected referential mapping structure. Node: " + node);
             }
 
-            @SuppressWarnings("unchecked")
-            Map<Object, Object> raw = (Map<Object, Object>) super.construct(node);
+            Map<?, ?> raw = (Map<?, ?>) super.construct(node);
 
             if (raw.containsKey(ConfigurationSerialization.SERIALIZED_TYPE_KEY)) {
                 Map<String, Object> typed = new LinkedHashMap<String, Object>(raw.size());
-                for (Map.Entry<Object, Object> entry : raw.entrySet()) {
+                for (Map.Entry<?, ?> entry : raw.entrySet()) {
                     typed.put(entry.getKey().toString(), entry.getValue());
                 }
 
diff --git a/src/main/java/org/bukkit/event/HandlerList.java b/src/main/java/org/bukkit/event/HandlerList.java
index f25b26fb..f48d942f 100644
--- a/src/main/java/org/bukkit/event/HandlerList.java
+++ b/src/main/java/org/bukkit/event/HandlerList.java
@@ -9,7 +9,6 @@ import java.util.Map.Entry;
 /**
  * A list of event handlers, stored per-event. Based on lahwran's fevents.
  */
-@SuppressWarnings("unchecked")
 public class HandlerList {
     /**
      * Handler array. This field being an array is the key to this system's speed.
@@ -203,6 +202,7 @@ public class HandlerList {
      *
      * @return the list of all handler lists
      */
+    @SuppressWarnings("unchecked")
     public static ArrayList<HandlerList> getHandlerLists() {
         return (ArrayList<HandlerList>) allLists.clone();
     }
diff --git a/src/main/java/org/bukkit/inventory/ItemStack.java b/src/main/java/org/bukkit/inventory/ItemStack.java
index 9118194b..b814fbec 100644
--- a/src/main/java/org/bukkit/inventory/ItemStack.java
+++ b/src/main/java/org/bukkit/inventory/ItemStack.java
@@ -391,10 +391,9 @@ public class ItemStack implements Cloneable, ConfigurationSerializable {
             Object raw = args.get("enchantments");
 
             if (raw instanceof Map) {
-                @SuppressWarnings("unchecked")
-                Map<Object, Object> map = (Map<Object, Object>) raw;
+                Map<?, ?> map = (Map<?, ?>) raw;
 
-                for (Map.Entry<Object, Object> entry : map.entrySet()) {
+                for (Map.Entry<?, ?> entry : map.entrySet()) {
                     Enchantment enchantment = Enchantment.getByName(entry.getKey().toString());
 
                     if ((enchantment != null) && (entry.getValue() instanceof Integer)) {
diff --git a/src/main/java/org/bukkit/permissions/Permission.java b/src/main/java/org/bukkit/permissions/Permission.java
index bfac37ab..abac6a9a 100644
--- a/src/main/java/org/bukkit/permissions/Permission.java
+++ b/src/main/java/org/bukkit/permissions/Permission.java
@@ -6,6 +6,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.logging.Level;
+
+import org.apache.commons.lang.Validate;
 import org.bukkit.Bukkit;
 import org.bukkit.plugin.PluginManager;
 
@@ -204,12 +206,12 @@ public class Permission {
      * @param def Default permission value to use if missing
      * @return Permission object
      */
-    public static List<Permission> loadPermissions(Map<String, Map<String, Object>> data, String error, PermissionDefault def) {
+    public static List<Permission> loadPermissions(Map<?, ?> data, String error, PermissionDefault def) {
         List<Permission> result = new ArrayList<Permission>();
 
-        for (Map.Entry<String, Map<String, Object>> entry : data.entrySet()) {
+        for (Map.Entry<?, ?> entry : data.entrySet()) {
             try {
-                result.add(Permission.loadPermission(entry.getKey(), entry.getValue(), def, result));
+                result.add(Permission.loadPermission(entry.getKey().toString(), (Map<?, ?>) entry.getValue(), def, result));
             } catch (Throwable ex) {
                 Bukkit.getServer().getLogger().log(Level.SEVERE, String.format(error, entry.getKey()), ex);
             }
@@ -248,13 +250,10 @@ public class Permission {
      * @param output A list to append any created child-Permissions to, may be null
      * @return Permission object
      */
-    public static Permission loadPermission(String name, Map<String, Object> data, PermissionDefault def, List<Permission> output) {
-        if (name == null) {
-            throw new IllegalArgumentException("Name cannot be null");
-        }
-        if (data == null) {
-            throw new IllegalArgumentException("Data cannot be null");
-        }
+    public static Permission loadPermission(String name, Map<?, ?> data, PermissionDefault def, List<Permission> output) {
+        Validate.notNull(name, "Name cannot be null");
+        Validate.notNull(data, "Data cannot be null");
+
         String desc = null;
         Map<String, Boolean> children = null;
 
@@ -280,11 +279,7 @@ public class Permission {
         }
 
         if (data.containsKey("description")) {
-            try {
-                desc = (String) data.get("description");
-            } catch (ClassCastException ex) {
-                throw new IllegalArgumentException("'description' key is of wrong type", ex);
-            }
+            desc = data.get("description").toString();
         }
 
         Permission result = new Permission(name, desc, def, children);
@@ -304,31 +299,30 @@ public class Permission {
         return result;
     }
 
-    @SuppressWarnings("unchecked")
-    private static Map<String, Boolean> extractChildren(Map<String, Object> data, String name, PermissionDefault def, List<Permission> output) {
-        Map<String, Object> input = (Map<String, Object>) data.get("children");
+    private static Map<String, Boolean> extractChildren(Map<?, ?> data, String name, PermissionDefault def, List<Permission> output) {
+        Map<?, ?> input = (Map<?, ?>) data.get("children");
         Map<String, Boolean> children = new LinkedHashMap<String, Boolean>();
 
-        for (Map.Entry<String, Object> entry : input.entrySet()) {
+        for (Map.Entry<?, ?> entry : input.entrySet()) {
             if ((entry.getValue() instanceof Boolean)) {
-                children.put(entry.getKey(), (Boolean) entry.getValue());
+                children.put(entry.getKey().toString(), (Boolean) entry.getValue());
             } else if ((entry.getValue() instanceof Map)) {
                 try {
                     try {
-                        Permission perm = loadPermission((String) entry.getKey(), (Map<String, Object>) entry.getValue(), def, output);
+                        Permission perm = loadPermission(entry.getKey().toString(), (Map<?, ?>) entry.getValue(), def, output);
                         children.put(perm.getName(), Boolean.valueOf(true));
 
                         if (output != null) {
                             output.add(perm);
                         }
                     } catch (Throwable ex) {
-                        Bukkit.getServer().getLogger().log(Level.SEVERE, "Permission node '" + (String) entry.getKey() + "' in child of " + name + " is invalid", ex);
+                        Bukkit.getServer().getLogger().log(Level.SEVERE, "Permission node '" + entry.getKey().toString() + "' in child of " + name + " is invalid", ex);
                     }
                 } catch (ClassCastException ex) {
-                    throw new IllegalArgumentException("Child '" + (String) entry.getKey() + "' contains invalid map type");
+                    throw new IllegalArgumentException("Child '" + entry.getKey().toString() + "' contains invalid map type");
                 }
             } else {
-                throw new IllegalArgumentException("Child '" + (String) entry.getKey() + "' contains invalid value");
+                throw new IllegalArgumentException("Child '" + entry.getKey().toString() + "' contains invalid value");
             }
         }
 
diff --git a/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java b/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
index 69f40968..34095d52 100644
--- a/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
+++ b/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
@@ -3,15 +3,18 @@ package org.bukkit.plugin;
 import java.io.InputStream;
 import java.io.Reader;
 import java.io.Writer;
-import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+
 import org.bukkit.permissions.Permission;
 import org.bukkit.permissions.PermissionDefault;
 import org.yaml.snakeyaml.Yaml;
 import org.yaml.snakeyaml.constructor.SafeConstructor;
 
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+
 /**
  * Provides access to a Plugins description file, plugin.yaml
  */
@@ -20,21 +23,20 @@ public final class PluginDescriptionFile {
     private String name = null;
     private String main = null;
     private String classLoaderOf = null;
-    private ArrayList<String> depend = null;
-    private ArrayList<String> softDepend = null;
+    private List<String> depend = null;
+    private List<String> softDepend = null;
     private String version = null;
-    private Object commands = null;
+    private Map<String, Map<String, Object>> commands = null;
     private String description = null;
-    private ArrayList<String> authors = new ArrayList<String>();
+    private List<String> authors = null;
     private String website = null;
     private boolean database = false;
     private PluginLoadOrder order = PluginLoadOrder.POSTWORLD;
-    private List<Permission> permissions = new ArrayList<Permission>();
+    private List<Permission> permissions = null;
     private PermissionDefault defaultPerm = PermissionDefault.OP;
 
-    @SuppressWarnings("unchecked")
     public PluginDescriptionFile(final InputStream stream) throws InvalidDescriptionException {
-        loadMap((Map<String, Object>) yaml.load(stream));
+        loadMap((Map<?, ?>) yaml.load(stream));
     }
 
     /**
@@ -43,9 +45,8 @@ public final class PluginDescriptionFile {
      * @param reader The reader
      * @throws InvalidDescriptionException If the PluginDescriptionFile is invalid
      */
-    @SuppressWarnings("unchecked")
     public PluginDescriptionFile(final Reader reader) throws InvalidDescriptionException {
-        loadMap((Map<String, Object>) yaml.load(reader));
+        loadMap((Map<?, ?>) yaml.load(reader));
     }
 
     /**
@@ -106,15 +107,15 @@ public final class PluginDescriptionFile {
         return main;
     }
 
-    public Object getCommands() {
+    public Map<String, Map<String, Object>> getCommands() {
         return commands;
     }
 
-    public Object getDepend() {
+    public List<String> getDepend() {
         return depend;
     }
 
-    public Object getSoftDepend() {
+    public List<String> getSoftDepend() {
         return softDepend;
     }
 
@@ -131,7 +132,7 @@ public final class PluginDescriptionFile {
         return description;
     }
 
-    public ArrayList<String> getAuthors() {
+    public List<String> getAuthors() {
         return authors;
     }
 
@@ -159,8 +160,7 @@ public final class PluginDescriptionFile {
         return classLoaderOf;
     }
 
-    @SuppressWarnings("unchecked")
-    private void loadMap(Map<String, Object> map) throws InvalidDescriptionException {
+    private void loadMap(Map<?, ?> map) throws InvalidDescriptionException {
         try {
             name = map.get("name").toString();
 
@@ -193,11 +193,28 @@ public final class PluginDescriptionFile {
         }
 
         if (map.containsKey("commands")) {
+            ImmutableMap.Builder<String, Map<String, Object>> commandsBuilder = ImmutableMap.<String, Map<String, Object>>builder();
             try {
-                commands = map.get("commands");
+                for (Map.Entry<?, ?> command : ((Map<?, ?>) map.get("commands")).entrySet()) {
+                    ImmutableMap.Builder<String, Object> commandBuilder = ImmutableMap.<String, Object>builder();
+                    for (Map.Entry<?, ?> commandEntry : ((Map<?, ?>) command.getValue()).entrySet()) {
+                        if (commandEntry.getValue() instanceof Iterable) {
+                            // This prevents internal alias list changes
+                            ImmutableList.Builder<Object> commandSubList = ImmutableList.<Object>builder();
+                            for (Object commandSubListItem : (Iterable<?>) commandEntry.getValue()) {
+                                commandSubList.add(commandSubListItem);
+                            }
+                            commandBuilder.put(commandEntry.getKey().toString(), commandSubList.build());
+                        } else {
+                            commandBuilder.put(commandEntry.getKey().toString(), commandEntry.getValue());
+                        }
+                    }
+                    commandsBuilder.put(command.getKey().toString(), commandBuilder.build());
+                }
             } catch (ClassCastException ex) {
                 throw new InvalidDescriptionException(ex, "commands are of wrong type");
             }
+            commands = commandsBuilder.build();
         }
 
         if (map.containsKey("class-loader-of")) {
@@ -205,19 +222,27 @@ public final class PluginDescriptionFile {
         }
 
         if (map.containsKey("depend")) {
+            ImmutableList.Builder<String> dependBuilder = ImmutableList.<String>builder();
             try {
-                depend = (ArrayList<String>) map.get("depend");
+                for (Object dependency : (Iterable<?>) map.get("depend")) {
+                    dependBuilder.add(dependency.toString());
+                }
             } catch (ClassCastException ex) {
                 throw new InvalidDescriptionException(ex, "depend is of wrong type");
             }
+            depend = dependBuilder.build();
         }
 
         if (map.containsKey("softdepend")) {
+            ImmutableList.Builder<String> softDependBuilder = ImmutableList.<String>builder();
             try {
-                softDepend = (ArrayList<String>) map.get("softdepend");
+                for (Object dependency : (Iterable<?>) map.get("softdepend")) {
+                    softDependBuilder.add(dependency.toString());
+                }
             } catch (ClassCastException ex) {
                 throw new InvalidDescriptionException(ex, "softdepend is of wrong type");
             }
+            softDepend = softDependBuilder.build();
         }
 
         if (map.containsKey("database")) {
@@ -229,19 +254,11 @@ public final class PluginDescriptionFile {
         }
 
         if (map.containsKey("website")) {
-            try {
-                website = (String) map.get("website");
-            } catch (ClassCastException ex) {
-                throw new InvalidDescriptionException(ex, "website is of wrong type");
-            }
+            website = map.get("website").toString();
         }
 
         if (map.containsKey("description")) {
-            try {
-                description = (String) map.get("description");
-            } catch (ClassCastException ex) {
-                throw new InvalidDescriptionException(ex, "description is of wrong type");
-            }
+            description = map.get("description").toString();
         }
 
         if (map.containsKey("load")) {
@@ -254,29 +271,28 @@ public final class PluginDescriptionFile {
             }
         }
 
-        if (map.containsKey("author")) {
-            try {
-                String extra = (String) map.get("author");
-
-                authors.add(extra);
-            } catch (ClassCastException ex) {
-                throw new InvalidDescriptionException(ex, "author is of wrong type");
-            }
-        }
-
         if (map.containsKey("authors")) {
+            ImmutableList.Builder<String> authorsBuilder = ImmutableList.<String>builder();
+            if (map.containsKey("author")) {
+                authorsBuilder.add(map.get("author").toString());
+            }
             try {
-                ArrayList<String> extra = (ArrayList<String>) map.get("authors");
-
-                authors.addAll(extra);
+                for (Object o : (Iterable<?>) map.get("authors")) {
+                    authorsBuilder.add(o.toString());
+                }
             } catch (ClassCastException ex) {
                 throw new InvalidDescriptionException(ex, "authors are of wrong type");
             }
+            authors = authorsBuilder.build();
+        } else if (map.containsKey("author")) {
+            authors = ImmutableList.of(map.get("author").toString());
+        } else {
+            authors = ImmutableList.<String>of();
         }
 
         if (map.containsKey("default-permission")) {
             try {
-                defaultPerm = PermissionDefault.getByName((String) map.get("default-permission"));
+                defaultPerm = PermissionDefault.getByName(map.get("default-permission").toString());
             } catch (ClassCastException ex) {
                 throw new InvalidDescriptionException(ex, "default-permission is of wrong type");
             } catch (IllegalArgumentException ex) {
@@ -286,12 +302,14 @@ public final class PluginDescriptionFile {
 
         if (map.containsKey("permissions")) {
             try {
-                Map<String, Map<String, Object>> perms = (Map<String, Map<String, Object>>) map.get("permissions");
+                Map<?, ?> perms = (Map<?, ?>) map.get("permissions");
 
-                permissions = Permission.loadPermissions(perms, "Permission node '%s' in plugin description file for " + getFullName() + " is invalid", defaultPerm);
+                permissions = ImmutableList.copyOf(Permission.loadPermissions(perms, "Permission node '%s' in plugin description file for " + getFullName() + " is invalid", defaultPerm));
             } catch (ClassCastException ex) {
                 throw new InvalidDescriptionException(ex, "permissions are of wrong type");
             }
+        } else {
+            permissions = ImmutableList.<Permission>of();
         }
     }
 
diff --git a/src/main/java/org/bukkit/plugin/SimplePluginManager.java b/src/main/java/org/bukkit/plugin/SimplePluginManager.java
index 1febcb8c..f23a59e2 100644
--- a/src/main/java/org/bukkit/plugin/SimplePluginManager.java
+++ b/src/main/java/org/bukkit/plugin/SimplePluginManager.java
@@ -99,7 +99,6 @@ public final class SimplePluginManager implements PluginManager {
      * @param directory Directory to check for plugins
      * @return A list of all plugins loaded
      */
-    @SuppressWarnings("unchecked")
     public Plugin[] loadPlugins(File directory) {
         Validate.notNull(directory, "Directory cannot be null");
         Validate.isTrue(directory.isDirectory(), "Directory must be a directory");
@@ -138,12 +137,12 @@ public final class SimplePluginManager implements PluginManager {
 
             plugins.put(description.getName(), file);
 
-            Collection<? extends String> softDependencySet = (Collection<? extends String>) description.getSoftDepend();
+            Collection<String> softDependencySet = description.getSoftDepend();
             if (softDependencySet != null) {
                 softDependencies.put(description.getName(), new LinkedList<String>(softDependencySet));
             }
 
-            Collection<? extends String> dependencySet = (Collection<? extends String>) description.getDepend();
+            Collection<String> dependencySet = description.getDepend();
             if (dependencySet != null) {
                 dependencies.put(description.getName(), new LinkedList<String>(dependencySet));
             }
diff --git a/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java b/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java
index 2766330d..cb0055b4 100644
--- a/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java
+++ b/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java
@@ -8,9 +8,9 @@ import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.net.URL;
-import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.jar.JarEntry;
@@ -40,6 +40,8 @@ import org.bukkit.plugin.TimedRegisteredListener;
 import org.bukkit.plugin.UnknownDependencyException;
 import org.yaml.snakeyaml.error.YAMLException;
 
+import com.google.common.collect.ImmutableList;
+
 /**
  * Represents a Java plugin loader, allowing plugins in the form of .jar
  */
@@ -53,7 +55,6 @@ public class JavaPluginLoader implements PluginLoader {
         server = instance;
     }
 
-    @SuppressWarnings("unchecked")
     public Plugin loadPlugin(File file) throws InvalidPluginException {
         Validate.notNull(file, "File cannot be null");
 
@@ -104,15 +105,9 @@ public class JavaPluginLoader implements PluginLoader {
             ));
         }
 
-        ArrayList<String> depend;
-
-        try {
-            depend = (ArrayList<String>) description.getDepend();
-            if (depend == null) {
-                depend = new ArrayList<String>();
-            }
-        } catch (ClassCastException ex) {
-            throw new InvalidPluginException(ex);
+        List<String> depend = description.getDepend();
+        if (depend == null) {
+            depend = ImmutableList.<String>of();
         }
 
         for (String pluginName : depend) {
@@ -251,8 +246,7 @@ public class JavaPluginLoader implements PluginLoader {
             classes.put(name, clazz);
 
             if (ConfigurationSerializable.class.isAssignableFrom(clazz)) {
-                @SuppressWarnings("unchecked")
-                Class<? extends ConfigurationSerializable> serializable = (Class<? extends ConfigurationSerializable>) clazz;
+                Class<? extends ConfigurationSerializable> serializable = clazz.asSubclass(ConfigurationSerializable.class);
                 ConfigurationSerialization.registerClass(serializable);
             }
         }
@@ -263,8 +257,7 @@ public class JavaPluginLoader implements PluginLoader {
 
         try {
             if ((clazz != null) && (ConfigurationSerializable.class.isAssignableFrom(clazz))) {
-                @SuppressWarnings("unchecked")
-                Class<? extends ConfigurationSerializable> serializable = (Class<? extends ConfigurationSerializable>) clazz;
+                Class<? extends ConfigurationSerializable> serializable = clazz.asSubclass(ConfigurationSerializable.class);
                 ConfigurationSerialization.unregisterClass(serializable);
             }
         } catch (NullPointerException ex) {
diff --git a/src/main/java/org/bukkit/potion/Potion.java b/src/main/java/org/bukkit/potion/Potion.java
index a66d1f91..e9c8e041 100644
--- a/src/main/java/org/bukkit/potion/Potion.java
+++ b/src/main/java/org/bukkit/potion/Potion.java
@@ -1,13 +1,14 @@
 package org.bukkit.potion;
 
 import java.util.Collection;
-import java.util.Collections;
 
 import org.apache.commons.lang.Validate;
 import org.bukkit.Material;
 import org.bukkit.entity.LivingEntity;
 import org.bukkit.inventory.ItemStack;
 
+import com.google.common.collect.ImmutableList;
+
 /**
  * Represents a minecraft potion
  */
@@ -170,9 +171,8 @@ public class Potion {
      * @see Potion#toDamageValue()
      * @return The effects that this potion applies
      */
-    @SuppressWarnings("unchecked")
     public Collection<PotionEffect> getEffects() {
-        if(type == null) return Collections.EMPTY_SET;
+        if (type == null) return ImmutableList.<PotionEffect>of();
         return getBrewer().getEffectsFromDamage(toDamageValue());
     }