Eclipse Plug-in Developer Guide (Galileo) - IPathVariableManager (Eclipse Platform API Specification)

Overview

Package

Class

Use

Tree

Deprecated

Index

Help

Eclipse Platform
Release 3.5

PREV CLASS NEXT CLASS

NO FRAMES

SUMMARY: NESTED | FIELD | CONSTR | METHOD

DETAIL: FIELD | CONSTR | METHOD

org.eclipse.core.resources
Interface IPathVariableManager

public interface IPathVariableManager

Manages a collection of path variables and resolves paths containing a variable reference.

A path variable is a pair of non-null elements (name,value) where name is a case-sensitive string (containing only letters, digits and the underscore character, and not starting with a digit), and value is an absolute IPath object.

Path variables allow for the creation of relative paths whose exact location in the file system depends on the value of a variable. A variable reference may only appear as the first segment of a relative path.

Since:: 2.1
See Also:: IPath
Restriction:: This interface is not intended to be implemented by clients.
Restriction:: This interface is not intended to be extended by clients.

Method Summary

void addChangeListener ( IPathVariableChangeListener listener)
          Registers the given listener to receive notification of changes to path variables.

String[] getPathVariableNames ()
          Returns an array containing all defined path variable names.

IPath getValue ( String name)
          Returns the value of the path variable with the given name.

boolean isDefined ( String name)
          Returns true if the given variable is defined and false otherwise.

void removeChangeListener ( IPathVariableChangeListener listener)
          Removes the given path variable change listener from the listeners list.

IPath resolvePath ( IPath path)
          Resolves a relative IPath object potentially containing a variable reference as its first segment, replacing the variable reference (if any) with the variable's value (which is a concrete absolute path).

URI resolveURI ( URI uri)
          Resolves a relative URI object potentially containing a variable reference as its first segment, replacing the variable reference (if any) with the variable's value (which is a concrete absolute URI).

void setValue ( String name, IPath value)
          Sets the path variable with the given name to be the specified value.

IStatus validateName ( String name)
          Validates the given name as the name for a path variable.

IStatus validateValue ( IPath path)
          Validates the given path as the value for a path variable.

Method Detail

setValue

void setValue(
String name,
              
IPath value)
              throws 
CoreException

Sets the path variable with the given name to be the specified value. Depending on the value given and if the variable is currently defined or not, there are several possible outcomes for this operation:

A new variable will be created, if there is no variable defined with the given name, and the given value is not null.
The referred variable's value will be changed, if it already exists and the given value is not null.
The referred variable will be removed, if a variable with the given name is currently defined and the given value is null.
The call will be ignored, if a variable with the given name is not currently defined and the given value is null, or if it is defined but the given value is equal to its current value.

If a variable is effectively changed, created or removed by a call to this method, notification will be sent to all registered listeners.

Parameters:

name - the name of the variable

value - the value for the variable (may be null)

Throws:


CoreException

- if this method fails. Reasons include:

The variable name is not valid
The variable value is relative

getValue


IPath getValue(
String name)

Returns the value of the path variable with the given name. If there is no variable defined with the given name, returns null.

Parameters:: name - the name of the variable to return the value for
Returns:: the value for the variable, or null if there is no variable defined with the given name

getPathVariableNames


String[] getPathVariableNames()

Returns an array containing all defined path variable names.

Returns:: an array containing all defined path variable names

addChangeListener

void addChangeListener(
IPathVariableChangeListener listener)

Registers the given listener to receive notification of changes to path variables. The listener will be notified whenever a variable has been added, removed or had its value changed. Has no effect if an identical path variable change listener is already registered.

Parameters:: listener - the listener
See Also:: IPathVariableChangeListener

removeChangeListener

void removeChangeListener(
IPathVariableChangeListener listener)

Removes the given path variable change listener from the listeners list. Has no effect if an identical listener is not registered.

Parameters:: listener - the listener
See Also:: IPathVariableChangeListener

resolveURI


URI resolveURI(
URI uri)

Resolves a relative URI object potentially containing a variable reference as its first segment, replacing the variable reference (if any) with the variable's value (which is a concrete absolute URI). If the given URI is absolute or has a non- null device then no variable substitution is done and that URI is returned as is. If the given URI is relative and has a null device, but the first segment does not correspond to a defined variable, then the URI is returned as is.

If the given URI is null then null will be returned. In all other cases the result will be non-null.

Parameters:: uri - the URI to be resolved
Returns:: the resolved URI or null
Since:: 3.2

resolvePath


IPath resolvePath(
IPath path)

Resolves a relative IPath object potentially containing a variable reference as its first segment, replacing the variable reference (if any) with the variable's value (which is a concrete absolute path). If the given path is absolute or has a non- null device then no variable substitution is done and that path is returned as is. If the given path is relative and has a null device, but the first segment does not correspond to a defined variable, then the path is returned as is.

If the given path is null then null will be returned. In all other cases the result will be non-null.

For example, consider the following collection of path variables:

TEMP = c:/temp
BACKUP = /tmp/backup

The following paths would be resolved as:

c:/bin => c:/bin

c:TEMP => c:TEMP

/TEMP => /TEMP

TEMP => c:/temp

TEMP/foo => c:/temp/foo

BACKUP => /tmp/backup

BACKUP/bar.txt => /tmp/backup/bar.txt

SOMEPATH/foo => SOMEPATH/foo

Parameters:: path - the path to be resolved
Returns:: the resolved path or null

isDefined

boolean isDefined(
String name)

Returns true if the given variable is defined and false otherwise. Returns false if the given name is not a valid path variable name.

Parameters:: name - the variable's name
Returns:: true if the variable exists, false otherwise

validateName


IStatus validateName(
String name)

Validates the given name as the name for a path variable. A valid path variable name is made exclusively of letters, digits and the underscore character, and does not start with a digit.

Parameters:: name - a possibly valid path variable name
Returns:: a status object with code IStatus.OK if the given name is a valid path variable name, otherwise a status object indicating what is wrong with the string
See Also:: IStatus.OK

validateValue


IStatus validateValue(
IPath path)

Validates the given path as the value for a path variable. A path variable value must be a valid path that is absolute.

Parameters:: path - a possibly valid path variable value
Returns:: a status object with code IStatus.OK if the given path is a valid path variable value, otherwise a status object indicating what is wrong with the value
See Also:: IPath.isValidPath(String), IStatus.OK