org.apache.tools.ant.types
Class DataType

java.lang.Object
  |
  +--org.apache.tools.ant.ProjectComponent
        |
        +--org.apache.tools.ant.types.DataType
Direct Known Subclasses:
AbstractFileSet, AbstractSelectorContainer, AntFilterReader, Assertions, BaseSelector, Description, ExtensionAdapter, ExtensionSet, FileList, FilterChain, FilterSet, ImageOperation, Mapper, Path, PatternSet, PropertySet, RedirectorElement, RegularExpression, Substitution, XMLCatalog

public abstract class DataType
extends ProjectComponent

Base class for those classes that can appear inside the build file as stand alone data types.

This class handles the common description attribute and provides a default implementation for reference handling and checking for circular references that is appropriate for types that can not be nested inside elements of the same type (i.e. <patternset> but not <path>).


Field Summary
protected  boolean checked
          Deprecated. The user should not be directly referencing variable. Please use setChecked(boolean) or isChecked() instead.
protected  java.lang.String description
          Deprecated. The user should not be directly referencing variable. Please use setDescription(java.lang.String) or getDescription() instead.
protected  Reference ref
          Deprecated. The user should not be directly referencing variable. Please use getRefid() instead.
 
Fields inherited from class org.apache.tools.ant.ProjectComponent
project
 
Constructor Summary
DataType()
           
 
Method Summary
protected  void checkAttributesAllowed()
          check that it is ok to set attributes, i.e that no reference is defined
protected  void checkChildrenAllowed()
          check that it is ok to add children, i.e that no reference is defined
protected  BuildException circularReference()
          Creates an exception that indicates the user has generated a loop of data types referencing each other.
protected  void dieOnCircularReference(java.util.Stack stack, Project project)
          Check to see whether any DataType we hold references to is included in the Stack (which holds all DataType instances that directly or indirectly reference this instance, including this instance itself).
protected  java.lang.Object getCheckedRef(java.lang.Class requiredClass, java.lang.String dataTypeName)
          Performs the check for circular references and returns the referenced object.
 java.lang.String getDescription()
          Return the description for the current data type.
protected  Reference getRefid()
          get the reference set on this object
protected  boolean isChecked()
           
 boolean isReference()
          Has the refid attribute of this element been set?
protected  BuildException noChildrenAllowed()
          Creates an exception that indicates that this XML element must not have child elements if the refid attribute is set.
protected  void setChecked(boolean checked)
           
 void setDescription(java.lang.String desc)
          Sets a description of the current data type.
 void setRefid(Reference ref)
          Set the value of the refid attribute.
protected  BuildException tooManyAttributes()
          Creates an exception that indicates that refid has to be the only attribute if it is set.
 
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
 

Field Detail

description

protected java.lang.String description
Deprecated. The user should not be directly referencing variable. Please use setDescription(java.lang.String) or getDescription() instead.

The description the user has set.


ref

protected Reference ref
Deprecated. The user should not be directly referencing variable. Please use getRefid() instead.

Value to the refid attribute.


checked

protected boolean checked
Deprecated. The user should not be directly referencing variable. Please use setChecked(boolean) or isChecked() instead.

Are we sure we don't hold circular references?

Subclasses are responsible for setting this value to false if we'd need to investigate this condition (usually because a child element has been added that is a subclass of DataType).

Constructor Detail

DataType

public DataType()
Method Detail

setDescription

public void setDescription(java.lang.String desc)
Sets a description of the current data type. It will be useful in commenting what we are doing.


getDescription

public java.lang.String getDescription()
Return the description for the current data type.


isReference

public boolean isReference()
Has the refid attribute of this element been set?


setRefid

public void setRefid(Reference ref)
Set the value of the refid attribute.

Subclasses may need to check whether any other attributes have been set as well or child elements have been created and thus override this method. if they do the must call super.setRefid.


dieOnCircularReference

protected void dieOnCircularReference(java.util.Stack stack,
                                      Project project)
                               throws BuildException
Check to see whether any DataType we hold references to is included in the Stack (which holds all DataType instances that directly or indirectly reference this instance, including this instance itself).

If one is included, throw a BuildException created by circularReference.

This implementation is appropriate only for a DataType that cannot hold other DataTypes as children.

The general contract of this method is that it shouldn't do anything if checked is true and set it to true on exit.

BuildException

getCheckedRef

protected java.lang.Object getCheckedRef(java.lang.Class requiredClass,
                                         java.lang.String dataTypeName)
Performs the check for circular references and returns the referenced object.


tooManyAttributes

protected BuildException tooManyAttributes()
Creates an exception that indicates that refid has to be the only attribute if it is set.


noChildrenAllowed

protected BuildException noChildrenAllowed()
Creates an exception that indicates that this XML element must not have child elements if the refid attribute is set.


circularReference

protected BuildException circularReference()
Creates an exception that indicates the user has generated a loop of data types referencing each other.


isChecked

protected boolean isChecked()

setChecked

protected void setChecked(boolean checked)

getRefid

protected Reference getRefid()
get the reference set on this object

Returns:
the reference or null

checkAttributesAllowed

protected void checkAttributesAllowed()
check that it is ok to set attributes, i.e that no reference is defined

Throws:
BuildException - if not allowed
Since:
Ant 1.6

checkChildrenAllowed

protected void checkChildrenAllowed()
check that it is ok to add children, i.e that no reference is defined

Throws:
BuildException - if not allowed
Since:
Ant 1.6


Copyright 2000-2005 Apache Software Foundation. All Rights Reserved.