weblogic.apache.xerces.validators.common
Class DFAContentModel

java.lang.Object
  |
  +--weblogic.apache.xerces.validators.common.DFAContentModel

public class DFAContentModel

extends java.lang.Object

implements XMLContentModel

DFAContentModel is the derivative of ContentModel that does all of the non-trivial element content validation. This class does the conversion from the regular expression to the DFA that it then uses in its validation algorithm.

This class is based on an implementation from the Apache XML Project. In future releases the XML parser, XSLT processor, and associated classes will likely be updated to be based on a later version of the Apache implementations. Since Apache does not guarantee backwards compatibility between versions of their software, we cannot guarantee backwards compatibility of any of the classes contained in the weblogic.apache package or sub-packages.

Version:

$Id: DFAContentModel.java,v 1.32 2001/06/20 20:54:37 neilg Exp $

Constructor Summary

DFAContentModel(CMNode syntaxTree, int leafCount)
Constructs a DFA content model.

DFAContentModel(CMNode syntaxTree, int leafCount, boolean dtd, boolean mixed)
Constructs a DFA content model.

Method Summary

boolean	checkLastChildEndingState()
void	checkUniqueParticleAttribution(SchemaGrammar gram)
ContentLeafNameTypeVector	getContentLeafNameTypeVector()
boolean	isFinalState(int state) check whether the given state is one of the final states
int	oneTransition(QName curElem, int[] stateStack, int curPos) one transition only
void	setSubstitutionGroupComparator(SubstitutionGroupComparator comparator)
int	validateContent(QName[] children, int offset, int length) Check that the specified content is valid according to this content model.
int	validateContent(QName[] children, int offset, int length, boolean parentCheck, int depth)
int	validateContentSpecial(QName[] children, int offset, int length)
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.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DFAContentModel

public DFAContentModel(CMNode syntaxTree,
                       int leafCount)
                throws CMException

Constructs a DFA content model.

Parameters:

stringPool - The string pool.

syntaxTree - The syntax tree of the content model.

leafCount - The number of leaves.

Throws:

CMException - Thrown if DMA can't be built.

DFAContentModel

public DFAContentModel(CMNode syntaxTree,
                       int leafCount,
                       boolean dtd,
                       boolean mixed)
                throws CMException

Constructs a DFA content model.

Parameters:

stringPool - The string pool.

syntaxTree - The syntax tree of the content model.

leafCount - The number of leaves.

Throws:

CMException - Thrown if DMA can't be built.

Method Detail

validateContent

public int validateContent(QName[] children,
                           int offset,
                           int length)
                    throws CMException

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.

Specified by:

validateContent in interface XMLContentModel

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:

CMException - Thrown on error.

validateContent

public int validateContent(QName[] children,
                           int offset,
                           int length,
                           boolean parentCheck,
                           int depth)
                    throws CMException

Specified by:

validateContent in interface XMLContentModel

checkLastChildEndingState

public boolean checkLastChildEndingState()

Specified by:

checkLastChildEndingState in interface XMLContentModel

validateContentSpecial

public int validateContentSpecial(QName[] children,
                                  int offset,
                                  int length)
                           throws java.lang.Exception

Specified by:

validateContentSpecial in interface XMLContentModel

isFinalState

public boolean isFinalState(int state)

check whether the given state is one of the final states

Parameters:

state - the state to check

Returns:

whether it's a final state

oneTransition

public int oneTransition(QName curElem,
                         int[] stateStack,
                         int curPos)
                  throws java.lang.Exception

one transition only

Parameters:

curElem - The current element's QName

stateStack - stack to store the previous state

curPos - the current position of the stack

Returns:

The value -1 if not valid, otherwise the index of the matching leaf

Throws:

CMException - Thrown on error.

setSubstitutionGroupComparator

public void setSubstitutionGroupComparator(SubstitutionGroupComparator comparator)

Specified by:

setSubstitutionGroupComparator in interface XMLContentModel

whatCanGoHere

public int whatCanGoHere(boolean fullyValid,
                         InsertableElementsInfo info)
                  throws CMException

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.

Specified by:

whatCanGoHere in interface XMLContentModel

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()

Specified by:

getContentLeafNameTypeVector in interface XMLContentModel

checkUniqueParticleAttribution

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

Specified by:

checkUniqueParticleAttribution in interface XMLContentModel