org.walkmod.util.location

Class LocationUtils

java.lang.Object

org.walkmod.util.location.LocationUtils

public class LocationUtils
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	LocationUtils.LocationFinder An finder or object locations

Field Summary

Fields

Modifier and Type	Field and Description
static String	UNKNOWN_STRING The string representation of an unknown location: " [unknown location]".

Method Summary

Modifier and Type	Method and Description
static void	addFinder(LocationUtils.LocationFinder finder) Add a LocationUtils.LocationFinder to the list of finders that will be queried for an object's location by getLocation(Object, String).
static Location	getLocation(Object obj) Get the location of an object.
static Location	getLocation(Object obj, String description) Get the location of an object.
static boolean	isKnown(Location location) Checks if a location is known, i.e. it is not null nor equal to LocationImpl.UNKNOWN.
static boolean	isUnknown(Location location) Checks if a location is unknown, i.e. it is either null or equal to LocationImpl.UNKNOWN.
static LocationImpl	parse(String text) Parse a location string of the form " uri:line:column" (e.g. " path/to/file.xml:3:40") to a Location object.
static String	toString(Location location) Builds a string representation of a location, in the " descripton - uri:line:column " format (e.g.

Methods inherited from class java.lang.Object

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

Field Detail

UNKNOWN_STRING

public static final String UNKNOWN_STRING

The string representation of an unknown location: " [unknown location]".

See Also:

Constant Field Values

Method Detail

toString

public static String toString(Location location)

Builds a string representation of a location, in the " descripton - uri:line:column " format (e.g. "foo - file://path/to/file.xml:3:40"). For an unknown location, returns UNKNOWN_STRING.

Parameters:

location - source location

Returns:

the string representation

parse

public static LocationImpl parse(String text)
                          throws IllegalArgumentException

Parse a location string of the form " uri:line:column" (e.g. " path/to/file.xml:3:40") to a Location object. Additionally, a description may also optionally be present, separated with an hyphen (e.g. "foo - path/to/file.xml:3.40").

Parameters:

text - the text to parse

Returns:

the location (possibly null if text was null or in an incorrect format)

Throws:

IllegalArgumentException

isKnown

public static boolean isKnown(Location location)

Checks if a location is known, i.e. it is not null nor equal to LocationImpl.UNKNOWN.

Parameters:

location - the location to check

Returns:

true if the location is known

isUnknown

public static boolean isUnknown(Location location)

Checks if a location is unknown, i.e. it is either null or equal to LocationImpl.UNKNOWN.

Parameters:

location - the location to check

Returns:

true if the location is unknown

addFinder

public static void addFinder(LocationUtils.LocationFinder finder)

Add a LocationUtils.LocationFinder to the list of finders that will be queried for an object's location by getLocation(Object, String).

Important: LocationUtils internally stores a weak reference to the finder. This avoids creating strong links between the classloader holding this class and the finder's classloader, which can cause some weird memory leaks if the finder's classloader is to be reloaded. Therefore, you have to keep a strong reference to the finder in the calling code, e.g.:

   private static LocationUtils.LocationFinder myFinder =
       new LocationUtils.LocationFinder() {
           public Location getLocation(Object obj, String desc) {
               ...
           }
       };
 
   static {
       LocationUtils.addFinder(myFinder);
   }
 

Parameters:

finder - the location finder to add

getLocation

public static Location getLocation(Object obj)

Get the location of an object. Some well-known located classes built in the JDK are handled by this method. Handling of other located classes can be handled by adding new location finders.

Parameters:

obj - the object of which to get the location

Returns:

the object's location, or LocationImpl.UNKNOWN if no location could be found

getLocation

public static Location getLocation(Object obj,
                                   String description)

Get the location of an object. Some well-known located classes built in the JDK are handled by this method. Handling of other located classes can be handled by adding new location finders.

Parameters:

obj - the object of which to get the location

description - an optional description of the object's location, used if a Location object has to be created.

Returns:

the object's location, or LocationImpl.UNKNOWN if no location could be found