Package org.joda.convert

Class RenameHandler

  • public final class RenameHandler
extends java.lang.Object
    A general purpose utility for registering renames.

    This handles type and enum constant renames. For example, use as follows: 

      RenameHandler.INSTANCE.renamedType("org.joda.OldName", NewName.class);
  RenameHandler.INSTANCE.renamedEnum("CORRECT", Status.VALID);
  RenameHandler.INSTANCE.renamedEnum("INCORRECT", Status.INVALID);
    From v2.1, renames can be stored on the classpath in configuration files. The file location is META-INF/org/joda/convert/Renamed.ini. All files found in this location are read and processed. The format has two sections [types] and [enums]. The [types] section has lines of the format oldClassName = newClassName. The [enums] section has lines of the format oldEnumConstantName = enumClassName.newEnumConstantName. Lines starting with # are treated as comments.

    The recommended usage is to edit the static singleton before using other classes. Editing a static is acceptable because renames are driven by bytecode which is static. For additional security, an application should lock the rename handler instance once any types and enums have been registered using lock().

    This class is thread-safe with concurrent caches.

    Since:
    1.6

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private java.util.concurrent.ConcurrentHashMap<java.lang.Class<?>,​java.util.Map<java.lang.String,​java.lang.Enum<?>>> enumRenames
      The enum renames.
      static RenameHandler INSTANCE
      A mutable global instance.
      private boolean locked
      The lock flag.
      private static boolean LOG
      Errors in class initialization are hard to debug.
      private java.util.concurrent.ConcurrentHashMap<java.lang.String,​java.lang.Class<?>> typeRenames
      The type renames.

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      private RenameHandler()
      Restricted constructor.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      private void checkNotLocked()  
      static RenameHandler create()
      Creates an instance.
      static RenameHandler create​(boolean loadFromClasspath)
      Creates an instance, providing the ability to load types in config files.
      private static RenameHandler createInstance()  
      java.util.Map<java.lang.String,​java.lang.Enum<?>> getEnumRenames​(java.lang.Class<?> type)
      Gets the map of renamed for an enum type.
      java.util.Set<java.lang.Class<?>> getEnumTypesWithRenames()
      Gets the set of enum types that have renames.
      java.util.Map<java.lang.String,​java.lang.Class<?>> getTypeRenames()
      Gets the map of renamed types.
      private void loadFromClasspath()  
      private java.util.List<java.lang.String> loadRenameFile​(java.net.URL url)  
      void lock()
      Locks this instance of the rename handler.
      <T extends java.lang.Enum<T>>
      T      		 lookupEnum​(java.lang.Class<T> type, java.lang.String name)
      Lookup an enum from a name, handling renames.
      java.lang.Class<?> lookupType​(java.lang.String name)
      Lookup a type from a name, handling renames.
      private void parseRenameFile​(java.util.List<java.lang.String> lines, java.net.URL url)  
      void renamedEnum​(java.lang.String oldName, java.lang.Enum<?> currentValue)
      Register the fact that an enum constant was renamed.
      void renamedType​(java.lang.String oldName, java.lang.Class<?> currentValue)
      Register the fact that a type was renamed.
      java.lang.String toString()  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Field Detail

      • LOG

        private static final boolean LOG
        Errors in class initialization are hard to debug. Set -Dorg.joda.convert.debug=true on the command line to add extra logging to System.err

        NOTE! This also forces StringConvert to be loaded before calling createInstance() which is vital to avoid horrid ordering issues when loading Renamed.ini classes that reference StringConvert.

      • INSTANCE

        public static final RenameHandler INSTANCE
        A mutable global instance. This is a singleton instance which is mutated. It will be populated by the contents of the Renamed.ini configuration files.

      • locked

        private volatile boolean locked
        The lock flag.

      • typeRenames

        private final java.util.concurrent.ConcurrentHashMap<java.lang.String,​java.lang.Class<?>> typeRenames
        The type renames.

      • enumRenames

        private final java.util.concurrent.ConcurrentHashMap<java.lang.Class<?>,​java.util.Map<java.lang.String,​java.lang.Enum<?>>> enumRenames
        The enum renames.

    • Constructor Detail

      • RenameHandler

        private RenameHandler()
        Restricted constructor.

    • Method Detail

      • create

        public static RenameHandler create()
        Creates an instance.

        This is not normally used as the preferred option is to edit the singleton.

        Returns:
        a new instance, not null

      • create

        public static RenameHandler create​(boolean loadFromClasspath)
        Creates an instance, providing the ability to load types in config files.

        This is not normally used as the preferred option is to edit the singleton.

        If the flag is set to true, the classpath config files will be used to register types and enums.

        Parameters:
        loadFromClasspath - whether to load any types in classpath config files
        Returns:
        a new instance, not null

      • renamedType

        public void renamedType​(java.lang.String oldName,
                        java.lang.Class<?> currentValue)
        Register the fact that a type was renamed.

        This handles the use case where a class is renamed.

        Parameters:
        oldName - the old name of the type including the package name, not null
        currentValue - the current type, not null

      • getTypeRenames

        public java.util.Map<java.lang.String,​java.lang.Class<?>> getTypeRenames()
        Gets the map of renamed types.

        An empty map is returned if there are no renames.

        Returns:
        a copy of the set of enum types with renames, not null

      • lookupType

        public java.lang.Class<?> lookupType​(java.lang.String name)
                              throws java.lang.ClassNotFoundException
        Lookup a type from a name, handling renames.
        Parameters:
        name - the name of the type to lookup, not null
        Returns:
        the type, not null
        Throws:
        java.lang.ClassNotFoundException - if the name is not a valid type

      • renamedEnum

        public void renamedEnum​(java.lang.String oldName,
                        java.lang.Enum<?> currentValue)
        Register the fact that an enum constant was renamed.

        This handles the use case where an enum constant is renamed, but the enum class remains the same.

        Parameters:
        oldName - the old name of the enum constant, not null
        currentValue - the current enum constant, not null

      • getEnumTypesWithRenames

        public java.util.Set<java.lang.Class<?>> getEnumTypesWithRenames()
        Gets the set of enum types that have renames.

        An empty set is returned if there are no renames.

        Returns:
        a copy of the set of enum types with renames, not null

      • getEnumRenames

        public java.util.Map<java.lang.String,​java.lang.Enum<?>> getEnumRenames​(java.lang.Class<?> type)
        Gets the map of renamed for an enum type.

        An empty map is returned if there are no renames.

        Parameters:
        type - the enum type, not null
        Returns:
        a copy of the set of enum renames, not null

      • lookupEnum

        public <T extends java.lang.Enum<T>> T lookupEnum​(java.lang.Class<T> type,
                                                  java.lang.String name)
        Lookup an enum from a name, handling renames.
        Type Parameters:
        T - the type of the desired enum
        Parameters:
        type - the enum type, not null
        name - the name of the enum to lookup, not null
        Returns:
        the enum value, not null
        Throws:
        java.lang.IllegalArgumentException - if the name is not a valid enum constant

      • lock

        public void lock()
        Locks this instance of the rename handler.

        For additional security, an application should lock the rename handler once any types and enums have been registered.

      • checkNotLocked

        private void checkNotLocked()

      • loadFromClasspath

        private void loadFromClasspath()

      • loadRenameFile

        private java.util.List<java.lang.String> loadRenameFile​(java.net.URL url)
                                                 throws java.io.IOException
        Throws:
        java.io.IOException

      • parseRenameFile

        private void parseRenameFile​(java.util.List<java.lang.String> lines,
                             java.net.URL url)

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object