Package adams.core.discovery

Class PropertyPath

java.lang.Object

adams.core.discovery.PropertyPath

public class PropertyPath
extends Object

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.

Using .get(X) it is possible to access the items of List objects, with "X" being the index for the "get(index)" method.

Author:

fracpete (fracpete at waikato dot ac dot nz)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PropertyPath.Path	Contains a (property) path structure.
static class	PropertyPath.PathElement	Represents a single element of a property path.
static class	PropertyPath.PathElementType	The type of path element we're dealing with.
static class	PropertyPath.PropertyContainer	A helper class that stores Object and PropertyDescriptor together.

Constructor Summary

Constructors

Constructor	Description
PropertyPath()

Method Summary

Modifier and Type	Method	Description
protected static PropertyPath.PropertyContainer	find(Object src, PropertyPath.Path current, PropertyPath.Path full, MessageCollection errors)	returns the property and object associated with the given path, null if a problem occurred.
static PropertyPath.PropertyContainer	find(Object src, PropertyPath.Path path, MessageCollection errors)	returns the property and object associated with the given path, null if a problem occurred.
static PropertyPath.PropertyContainer	find(Object src, String path, MessageCollection errors)	returns the property and object associated with the given path, null if a problem occurred.
static Object	getValue(Object src, PropertyPath.Path path, MessageCollection errors)	returns the value specified by the given path from the object.
static Object	getValue(Object src, String path, MessageCollection errors)	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, MessageCollection errors)	set the given value specified by the given path in the object.
static boolean	setValue(Object src, String path, Object value, MessageCollection errors)	set the given value specified by the given path in the object.

Methods inherited from class java.lang.Object

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

Constructor Detail

PropertyPath

public PropertyPath()

Method Detail

find

public static PropertyPath.PropertyContainer find(Object src,
                                                  String path,
                                                  MessageCollection errors)

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

find

public static PropertyPath.PropertyContainer find(Object src,
                                                  PropertyPath.Path path,
                                                  MessageCollection errors)

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

find

protected static PropertyPath.PropertyContainer find(Object src,
                                                     PropertyPath.Path current,
                                                     PropertyPath.Path full,
                                                     MessageCollection errors)

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

Parameters:

src - the object to start from

current - the path to follow

full - the full path

Returns:

not null, if the property could be found

getValue

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

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,
                              MessageCollection errors)

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,
                               MessageCollection errors)

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 boolean setValue(Object src,
                               String path,
                               Object value,
                               MessageCollection errors)

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 succesfully set

main

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

for testing only.

Parameters:

args - the commandline options - ignored

Throws:

Exception - if something goes wrong