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Home » apache-ant-1.8.1 » org.apache.tools » ant » types » [javadoc | source]
org.apache.tools.ant.types
abstract public class: DataType [javadoc | source]
java.lang.Object
   org.apache.tools.ant.ProjectComponent
      org.apache.tools.ant.types.DataType

All Implemented Interfaces:
    Cloneable

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  Reference ref    Value to the refid attribute.
     
    protected  boolean checked    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).

       
      Fields inherited from org.apache.tools.ant.ProjectComponent:
      project,  location,  description
      Method from org.apache.tools.ant.types.DataType Summary:
      checkAttributesAllowed,   checkChildrenAllowed,   circularReference,   clone,   dieOnCircularReference,   dieOnCircularReference,   dieOnCircularReference,   getCheckedRef,   getCheckedRef,   getCheckedRef,   getCheckedRef,   getDataTypeName,   getRefid,   invokeCircularReferenceCheck,   isChecked,   isReference,   noChildrenAllowed,   pushAndInvokeCircularReferenceCheck,   setChecked,   setRefid,   toString,   tooManyAttributes
      Methods from org.apache.tools.ant.ProjectComponent:
      clone,   getDescription,   getLocation,   getProject,   log,   log,   setDescription,   setLocation,   setProject
      Methods from java.lang.Object:
      clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
      Method from org.apache.tools.ant.types.DataType Detail:
       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.
       public Object clone() throws CloneNotSupportedException 
       protected  void dieOnCircularReference() 
        Convenience method.
       protected  void dieOnCircularReference(Project p) 
        Convenience method.
       protected  void dieOnCircularReference(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.

       protected Object getCheckedRef() 
        Performs the check for circular references and returns the referenced object.
       protected Object getCheckedRef(Project p) 
        Performs the check for circular references and returns the referenced object.
       protected Object getCheckedRef(Class requiredClass,
          String dataTypeName) 
        Performs the check for circular references and returns the referenced object.
       protected Object getCheckedRef(Class requiredClass,
          String dataTypeName,
          Project project) 
        Performs the check for circular references and returns the referenced object. This version allows the fallback Project instance to be specified.
       protected String getDataTypeName() 
        Gets as descriptive as possible a name used for this datatype instance.
       public Reference getRefid() 
        get the reference set on this object
       public static  void invokeCircularReferenceCheck(DataType dt,
          Stack stk,
          Project p) 
        Allow DataTypes outside org.apache.tools.ant.types to indirectly call dieOnCircularReference on nested DataTypes.
       protected boolean isChecked() 
        The flag that is used to indicate that circular references have been checked.
       public 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.
       public static  void pushAndInvokeCircularReferenceCheck(DataType dt,
          Stack stk,
          Project p) 
        Allow DataTypes outside org.apache.tools.ant.types to indirectly call dieOnCircularReference on nested DataTypes.

        Pushes dt on the stack, runs dieOnCircularReference and pops it again.

       protected  void setChecked(boolean checked) 
        Set the flag that is used to indicate that circular references have been checked.
       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.

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