weka.core
Class PropertyPath

java.lang.Object
  weka.core.PropertyPath

All Implemented Interfaces:

RevisionHandler

public class PropertyPath
extends Object
implements RevisionHandler

A helper class for accessing properties in nested objects, e.g., accessing the "getRidge" method of a LinearRegression classifier part of MultipleClassifierCombiner, e.g., Vote. For doing so, one needs to supply the object to work on and a property path. The property path is a dot delimited path of property names ("getFoo()" and "setFoo(int)" have "foo" as property name), indices of arrays are 0-based. E.g.:

getPropertyDescriptor(vote, "classifiers[1].ridge") will return the second classifier (which should be our LinearRegression) of the given Vote meta-classifier and there the property descriptor of the "ridge" property. getValue(...) will return the actual value of the ridge parameter and setValue(...) will set it.

Version:

$Revision: 8034 $

Author:

fracpete (fracpete at waikato dot ac dot nz)

Nested Class Summary

static class	PropertyPath.Path Contains a (property) path structure
static class	PropertyPath.PathElement Represents a single element of a property path

Constructor Summary

PropertyPath()

Method Summary

static weka.core.PropertyPath.PropertyContainer	find(Object src, PropertyPath.Path path) returns the property and object associated with the given path, null if a problem occurred.
static PropertyDescriptor	getPropertyDescriptor(Object src, PropertyPath.Path path) returns the property associated with the given path, null if a problem occurred.
static PropertyDescriptor	getPropertyDescriptor(Object src, String path) returns the property associated with the given path
String	getRevision() Returns the revision string.
static Object	getValue(Object src, PropertyPath.Path path) returns the value specified by the given path from the object
static Object	getValue(Object src, String path) returns the value specified by the given path from the object
static void	main(String[] args) for testing only
static boolean	setValue(Object src, PropertyPath.Path path, Object value) set the given value specified by the given path in the object
static void	setValue(Object src, String path, Object value) set the given value specified by the given path in the object

Methods inherited from class java.lang.Object

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

Constructor Detail

PropertyPath

public PropertyPath()

Method Detail

find

public static weka.core.PropertyPath.PropertyContainer find(Object src,
                                                            PropertyPath.Path path)

returns the property and object associated with the given path, null if a problem occurred.

Parameters:

src - the object to start from

path - the path to follow

Returns:

not null, if the property could be found

getPropertyDescriptor

public static PropertyDescriptor getPropertyDescriptor(Object src,
                                                       PropertyPath.Path path)

returns the property associated with the given path, null if a problem occurred.

Parameters:

src - the object to start from

path - the path to follow

Returns:

not null, if the property could be found

getPropertyDescriptor

public static PropertyDescriptor getPropertyDescriptor(Object src,
                                                       String path)

returns the property associated with the given path

Parameters:

src - the object to start from

path - the path to follow

Returns:

not null, if the property could be found

getValue

public static Object getValue(Object src,
                              PropertyPath.Path path)

returns the value specified by the given path from the object

Parameters:

src - the object to work on

path - the retrieval path

Returns:

the value, null if an error occurred

getValue

public static Object getValue(Object src,
                              String path)

returns the value specified by the given path from the object

Parameters:

src - the object to work on

path - the retrieval path

Returns:

the value, null if an error occurred

setValue

public static boolean setValue(Object src,
                               PropertyPath.Path path,
                               Object value)

set the given value specified by the given path in the object

Parameters:

src - the object to work on

path - the retrieval path

value - the value to set

Returns:

true if the value could be set

setValue

public static void setValue(Object src,
                            String path,
                            Object value)

set the given value specified by the given path in the object

Parameters:

src - the object to work on

path - the retrieval path

value - the value to set

getRevision

public String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision

main

public static void main(String[] args)
                 throws Exception

for testing only

Parameters:

args - the commandline options - ignored

Throws:

Exception - if something goes wrong