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

java.lang.Object
  extended by org.apache.tools.ant.ProjectComponent
      extended by org.apache.tools.ant.types.DataType
          extended by org.apache.tools.ant.types.selectors.BaseSelector
All Implemented Interfaces:
java.lang.Cloneable, FileSelector
Direct Known Subclasses:
BaseExtendSelector, BaseSelectorContainer, ExtendSelector, MappingSelector, PresentSelector, ScriptSelector

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

Field Summary
 
Fields inherited from class org.apache.tools.ant.types.DataType
checked, ref
 
Fields inherited from class org.apache.tools.ant.ProjectComponent
description, location, 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
checkAttributesAllowed, checkChildrenAllowed, circularReference, clone, dieOnCircularReference, dieOnCircularReference, dieOnCircularReference, getCheckedRef, getCheckedRef, getCheckedRef, getCheckedRef, getDataTypeName, getRefid, invokeCircularReferenceCheck, isChecked, isReference, noChildrenAllowed, pushAndInvokeCircularReferenceCheck, setChecked, setRefid, tooManyAttributes, toString
 
Methods inherited from class org.apache.tools.ant.ProjectComponent
getDescription, getLocation, getProject, log, log, setDescription, setLocation, setProject
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, 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