org.apache.xerces.validators.common
Interface XMLContentModel

All Known Implementing Classes:
MixedContentModel, DFAContentModel, SimpleContentModel, AllContentModel

public interface XMLContentModel

ContentModel is an interface that can be used by your own custom validators to plug in various types of content models. It is used internally as well for the same purposes.

Since there are a number of optimizations that can be used for simple or special content models, this class provides the interface via which all of the various content model types are managed. So the validation handler class has a list of things derived from this class. It finds the one for the desired element, then asks it to validate the element contents.

The validation interface from the scanner to the validation handle provides a child count and an array of element name indices into the string pool. So it is assumed that those same parameters will be passed to the content model to be validated. Therefore the validateContent() method accepts this standard view of the elements to be validated.

Version:
$Id: XMLContentModel.java 317282 2001-06-20 20:54:40Z neilg $
Author:
Dean Roddey, Eric Ye

Method Summary
 void checkUniqueParticleAttribution(SchemaGrammar gram)
           
 ContentLeafNameTypeVector getContentLeafNameTypeVector()
           
 void setSubstitutionGroupComparator(SubstitutionGroupComparator comparator)
          The setter method to pass in the SubstitutionGroupComparator.
 int validateContent(QName[] children, int offset, int length)
          Check that the specified content is valid according to this content model.
 int validateContentSpecial(QName[] children, int offset, int length)
          This method is different from "validateContent" in that it will try to use the SubstitutionGroupComparator to match children against the content model.
 int whatCanGoHere(boolean fullyValid, InsertableElementsInfo info)
          Returns information about which elements can be placed at a particular point in the passed element's content model.
 

Method Detail

validateContent

public int validateContent(QName[] children,
                           int offset,
                           int length)
                    throws java.lang.Exception
Check that the specified content is valid according to this content model. This method can also be called to do 'what if' testing of content models just to see if they would be valid.

A value of -1 in the children array indicates a PCDATA node. All other indexes will be positive and represent child elements. The count can be zero, since some elements have the EMPTY content model and that must be confirmed.

Parameters:
children - The children of this element. Each integer is an index within the StringPool of the child element name. An index of -1 is used to indicate an occurrence of non-whitespace character data.
offset - Offset into the array where the children starts.
length - The number of entries in the children array.
Returns:
The value -1 if fully valid, else the 0 based index of the child that first failed. If the value returned is equal to the number of children, then the specified children are valid but additional content is required to reach a valid ending state.
Throws:
java.lang.Exception - Thrown on error.

validateContentSpecial

public int validateContentSpecial(QName[] children,
                                  int offset,
                                  int length)
                           throws java.lang.Exception
This method is different from "validateContent" in that it will try to use the SubstitutionGroupComparator to match children against the content model.

A value of -1 in the children array indicates a PCDATA node. All other indexes will be positive and represent child elements. The count can be zero, since some elements have the EMPTY content model and that must be confirmed.

Parameters:
children - The children of this element. Each integer is an index within the StringPool of the child element name. An index of -1 is used to indicate an occurrence of non-whitespace character data.
offset - Offset into the array where the children starts.
length - The number of entries in the children array.
Returns:
The value -1 if fully valid, else the 0 based index of the child that first failed. If the value returned is equal to the number of children, then the specified children are valid but additional content is required to reach a valid ending state.
Throws:
java.lang.Exception - Thrown on error.

setSubstitutionGroupComparator

public void setSubstitutionGroupComparator(SubstitutionGroupComparator comparator)
The setter method to pass in the SubstitutionGroupComparator.
Parameters:
comparator - a SubstitutionGroupComparator object.
Returns:
 
Throws:
-  

whatCanGoHere

public int whatCanGoHere(boolean fullyValid,
                         InsertableElementsInfo info)
                  throws java.lang.Exception
Returns information about which elements can be placed at a particular point in the passed element's content model.

Note that the incoming content model to test must be valid at least up to the insertion point. If not, then -1 will be returned and the info object will not have been filled in.

If, on return, the info.isValidEOC flag is set, then the 'insert after' element is a valid end of content. In other words, nothing needs to be inserted after it to make the parent element's content model valid.

Parameters:
fullyValid - Only return elements that can be inserted and still maintain the validity of subsequent elements past the insertion point (if any). If the insertion point is at the end, and this is true, then only elements that can be legal final states will be returned.
info - An object that contains the required input data for the method, and which will contain the output information if successful.
Returns:
The value -1 if fully valid, else the 0 based index of the child that first failed before the insertion point. If the value returned is equal to the number of children, then the specified children are valid but additional content is required to reach a valid ending state.
See Also:
InsertableElementsInfo

getContentLeafNameTypeVector

public ContentLeafNameTypeVector getContentLeafNameTypeVector()

checkUniqueParticleAttribution

public void checkUniqueParticleAttribution(SchemaGrammar gram)
                                    throws java.lang.Exception


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