org.apache.tools.ant.types

Class DataType

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 booleanchecked
Are we sure we don't hold circular references?
protected Stringdescription
The description the user has set.
protected Referenceref
Value to the refid attribute.
Method Summary
protected voidcheckAttributesAllowed()
check that it is ok to set attributes, i.e that no reference is defined
protected voidcheckChildrenAllowed()
check that it is ok to add children, i.e that no reference is defined
protected BuildExceptioncircularReference()
Creates an exception that indicates the user has generated a loop of data types referencing each other.
protected voiddieOnCircularReference(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 ObjectgetCheckedRef(Class requiredClass, String dataTypeName)
Performs the check for circular references and returns the referenced object.
StringgetDescription()
Return the description for the current data type.
protected ReferencegetRefid()
get the reference set on this object
protected booleanisChecked()
booleanisReference()
Has the refid attribute of this element been set?
protected BuildExceptionnoChildrenAllowed()
Creates an exception that indicates that this XML element must not have child elements if the refid attribute is set.
protected voidsetChecked(boolean checked)
voidsetDescription(String desc)
Sets a description of the current data type.
voidsetRefid(Reference ref)
Set the value of the refid attribute.
protected BuildExceptiontooManyAttributes()
Creates an exception that indicates that refid has to be the only attribute if it is set.

Field Detail

checked

protected boolean checked

Deprecated: The user should not be directly referencing variable. Please use {@link #setChecked} or {@link #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).

description

protected String description

Deprecated: The user should not be directly referencing variable. Please use {@link #setDescription} or {@link #getDescription} instead.

The description the user has set.

ref

protected Reference ref

Deprecated: The user should not be directly referencing variable. Please use {@link #getRefid} instead.

Value to the refid attribute.

Method Detail

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

circularReference

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

dieOnCircularReference

protected void dieOnCircularReference(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).

If one is included, throw a BuildException created by {@link #circularReference 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 {@link #checked checked} is true and set it to true on exit.

getCheckedRef

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

getDescription

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

getRefid

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

Returns: the reference or null

isChecked

protected boolean isChecked()

isReference

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

setChecked

protected void setChecked(boolean checked)

setDescription

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

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.

tooManyAttributes

protected BuildException tooManyAttributes()
Creates an exception that indicates that refid has to be the only attribute if it is set.
Copyright B) 2000-2007 Apache Software Foundation. All Rights Reserved.