GUAC-1170: Use checked versions of empty list/set/map.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/base/ModeledDirectoryObjectService.java

@@ -316,7 +316,7 @@ public abstract class ModeledDirectoryObjectService<InternalType extends Modeled
 
         // Do not query if no identifiers given
         if (identifiers.isEmpty())
-            return Collections.EMPTY_LIST;
+            return Collections.<InternalType>emptyList();
 
         Collection<ModelType> objects;
 

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/base/ModeledGroupedDirectoryObjectService.java

@@ -96,7 +96,7 @@ public abstract class ModeledGroupedDirectoryObjectService<InternalType extends
 
             // If both parents have the same identifier, nothing has changed
             if (parentIdentifier != null && parentIdentifier.equals(oldParentIdentifier))
-                return Collections.EMPTY_LIST;
+                return Collections.<String>emptyList();
 
         }
 

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/tunnel/AbstractGuacamoleTunnelService.java

@@ -424,12 +424,12 @@ public abstract class AbstractGuacamoleTunnelService implements GuacamoleTunnelS
 
         // If not a balancing group, there are no balanced connections
         if (connectionGroup.getType() != ConnectionGroup.Type.BALANCING)
-            return Collections.EMPTY_LIST;
+            return Collections.<ModeledConnection>emptyList();
 
         // If group has no children, there are no balanced connections
         Collection<String> identifiers = connectionMapper.selectIdentifiersWithin(connectionGroup.getIdentifier());
         if (identifiers.isEmpty())
-            return Collections.EMPTY_LIST;
+            return Collections.<ModeledConnection>emptyList();
 
         // Retrieve all children
         Collection<ConnectionModel> models = connectionMapper.select(identifiers);
@@ -453,7 +453,7 @@ public abstract class AbstractGuacamoleTunnelService implements GuacamoleTunnelS
         // Simply return empty list if there are no active tunnels
         Collection<ActiveConnectionRecord> records = activeTunnels.values();
         if (records.isEmpty())
-            return Collections.EMPTY_LIST;
+            return Collections.<ActiveConnectionRecord>emptyList();
 
         // Build set of all connection identifiers associated with active tunnels
         Set<String> identifiers = new HashSet<String>(records.size());
@@ -521,7 +521,7 @@ public abstract class AbstractGuacamoleTunnelService implements GuacamoleTunnelS
 
         // If not a balancing group, assume no connections
         if (connectionGroup.getType() != ConnectionGroup.Type.BALANCING)
-            return Collections.EMPTY_LIST;
+            return Collections.<ActiveConnectionRecord>emptyList();
 
         return activeConnectionGroups.get(connectionGroup.getIdentifier());
 

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/tunnel/ActiveConnectionMultimap.java

@@ -120,7 +120,7 @@ public class ActiveConnectionMultimap {
             if (connections != null)
                 return Collections.unmodifiableCollection(connections);
 
-            return Collections.EMPTY_LIST;
+            return Collections.<ActiveConnectionRecord>emptyList();
 
         }
     }

guacamole-ext/src/main/java/org/glyptodon/guacamole/net/auth/credentials/CredentialsInfo.java

@@ -65,7 +65,7 @@ public class CredentialsInfo {
      * CredentialsInfo object which describes empty credentials. No parameters
      * are required.
      */
-    public static final CredentialsInfo EMPTY = new CredentialsInfo(Collections.EMPTY_LIST);
+    public static final CredentialsInfo EMPTY = new CredentialsInfo(Collections.<Parameter>emptyList());
 
     /**
      * CredentialsInfo object which describes standard username/password

guacamole-ext/src/main/java/org/glyptodon/guacamole/net/auth/simple/SimpleConnection.java

@@ -117,7 +117,7 @@ public class SimpleConnection extends AbstractConnection {
 
     @Override
     public List<ConnectionRecord> getHistory() throws GuacamoleException {
-        return Collections.EMPTY_LIST;
+        return Collections.<ConnectionRecord>emptyList();
     }
 
 }

guacamole-ext/src/main/java/org/glyptodon/guacamole/net/auth/simple/SimpleDirectory.java

@@ -45,7 +45,7 @@ public class SimpleDirectory<ObjectType> implements Directory<ObjectType> {
     /**
      * The Map of objects to provide access to.
      */
-    private Map<String, ObjectType> objects = Collections.EMPTY_MAP;
+    private Map<String, ObjectType> objects = Collections.<String, ObjectType>emptyMap();
 
     /**
      * Creates a new empty SimpleDirectory which does not provide access to

guacamole-ext/src/main/java/org/glyptodon/guacamole/net/auth/simple/SimpleObjectPermissionSet.java

@@ -42,7 +42,7 @@ public class SimpleObjectPermissionSet implements ObjectPermissionSet {
     /**
      * The set of all permissions currently granted.
      */
-    private Set<ObjectPermission> permissions = Collections.EMPTY_SET;
+    private Set<ObjectPermission> permissions = Collections.<ObjectPermission>emptySet();
 
     /**
      * Creates a new empty SimpleObjectPermissionSet.

guacamole-ext/src/main/java/org/glyptodon/guacamole/net/auth/simple/SimpleSystemPermissionSet.java

@@ -40,7 +40,7 @@ public class SimpleSystemPermissionSet implements SystemPermissionSet {
     /**
      * The set of all permissions currently granted.
      */
-    private Set<SystemPermission> permissions = Collections.EMPTY_SET;
+    private Set<SystemPermission> permissions = Collections.<SystemPermission>emptySet();
 
     /**
      * Creates a new empty SimpleSystemPermissionSet.

guacamole-ext/src/main/java/org/glyptodon/guacamole/net/auth/simple/SimpleUserContext.java

@@ -126,7 +126,7 @@ public class SimpleUserContext implements UserContext {
         // Add root group that contains only the given configurations
         this.rootGroup = new SimpleConnectionGroup(
             ROOT_IDENTIFIER, ROOT_IDENTIFIER,
-            connectionIdentifiers, Collections.EMPTY_LIST
+            connectionIdentifiers, Collections.<String>emptyList()
         );
 
         // Build new user from credentials

guacamole/src/main/java/org/glyptodon/guacamole/net/basic/rest/connection/APIConnectionWrapper.java

@@ -122,7 +122,7 @@ public class APIConnectionWrapper implements Connection {
 
     @Override
     public List<? extends ConnectionRecord> getHistory() throws GuacamoleException {
-        return Collections.EMPTY_LIST;
+        return Collections.<ConnectionRecord>emptyList();
     }
     
 }

guacamole/src/main/java/org/glyptodon/guacamole/net/basic/rest/language/LanguageRESTService.java

@@ -108,7 +108,7 @@ public class LanguageRESTService {
         
         // If no translation files found, return an empty map
         if (resourcePaths == null)
-            return Collections.EMPTY_MAP;
+            return Collections.<String, String>emptyMap();
         
         Map<String, String> languageMap = new HashMap<String, String>();