BaseSelector (Apache Ant API)

org.apache.tools.ant.types.selectors
Class BaseSelector


java.lang.Object

  |

  +--org.apache.tools.ant.ProjectComponent

        |

        +--org.apache.tools.ant.types.DataType

              |

              +--org.apache.tools.ant.types.selectors.BaseSelector

All Implemented Interfaces:
FileSelector
Direct Known Subclasses:
BaseExtendSelector, BaseSelectorContainer, DependSelector, ExtendSelector, PresentSelector

public abstract class BaseSelector
extends DataType
implements FileSelector

A convenience base class that you can subclass Selectors from. It provides some helpful common behaviour. Note that there is no need for Selectors to inherit from this class, it is only necessary that they implement FileSelector.

Since:
1.5
Author:
Bruce Atherton

Field Summary
 
Fields inherited from class org.apache.tools.ant.types.DataType
checked, description, ref
 
Fields inherited from class org.apache.tools.ant.ProjectComponent
project
 
Constructor Summary
BaseSelector()
          Do nothing constructor.
 
Method Summary
 java.lang.String getError()
          Returns any error messages that have been set.
abstract  boolean isSelected(java.io.File basedir, java.lang.String filename, java.io.File file)
          Method that each selector will implement to create their selection behaviour.
 void setError(java.lang.String msg)
          Allows all selectors to indicate a setup error.
 void validate()
          Subclasses can use this to throw the requisite exception in isSelected() in the case of an error condition.
 void verifySettings()
          Subclasses can override this method to provide checking of their state.
 
Methods inherited from class org.apache.tools.ant.types.DataType
circularReference, dieOnCircularReference, getCheckedRef, getDescription, isReference, noChildrenAllowed, setDescription, setRefid, tooManyAttributes
 
Methods inherited from class org.apache.tools.ant.ProjectComponent
getProject, log, log, setProject
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

BaseSelector


public BaseSelector()
Do nothing constructor.

Method Detail

setError


public void setError(java.lang.String msg)
Allows all selectors to indicate a setup error. Note that only the first error message is recorded.

Parameters:
msg - The error message any BuildException should throw.

getError


public java.lang.String getError()
Returns any error messages that have been set.

Returns:
the error condition

verifySettings


public void verifySettings()

Subclasses can override this method to provide checking of their state. So long as they call validate() from isSelected(), this will be called automatically (unless they override validate()).

Implementations should check for incorrect settings and call setError() as necessary.


validate


public void validate()
Subclasses can use this to throw the requisite exception in isSelected() in the case of an error condition.


isSelected


public abstract boolean isSelected(java.io.File basedir,
                                   java.lang.String filename,
                                   java.io.File file)
Method that each selector will implement to create their selection behaviour. If there is a problem with the setup of a selector, it can throw a BuildException to indicate the problem.

Specified by:
isSelected in interface FileSelector
Parameters:
basedir - A java.io.File object for the base directory
filename - The name of the file to check
file - A File object for this filename
Returns:
whether the file should be selected or not


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