/*
* @(#)$Id: IdentityConstraintState.java,v 1.3 2001/08/08 23:58:26 Bear Exp $
*
* Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
*
* This software is the proprietary information of Sun Microsystems, Inc.
* Use is subject to license terms.
*
*/
package com.sun.msv.reader.xmlschema;
import com.sun.msv.reader.ChildlessState;
import com.sun.msv.reader.SimpleState;
import com.sun.msv.grammar.NameClass;
import com.sun.msv.grammar.SimpleNameClass;
import com.sun.msv.grammar.NamespaceNameClass;
import com.sun.msv.grammar.AnyNameClass;
import com.sun.msv.grammar.xmlschema.*;
import com.sun.msv.util.StartTagInfo;
import com.sun.msv.reader.GrammarReader;
import com.sun.msv.reader.State;
import org.xml.sax.Locator;
import java.util.Vector;
import java.util.StringTokenizer;
/**
* used to parse <unique>,<key>, and <keyref> element.
*
* @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
*/
public class IdentityConstraintState extends SimpleState {
protected XPath[] selector;
protected final Vector fields = new Vector();
protected State createChildState( StartTagInfo tag ) {
if(tag.localName.equals("selector")) {
String v = tag.getAttribute("xpath");
if(v!=null)
selector = parseSelector(v);
else {
reader.reportError(reader.ERR_MISSING_ATTRIBUTE, "selector", "xpath" );
selector = new XPath[0]; // recover by providing a dummy selector
}
return new ChildlessState();
}
if(tag.localName.equals("field")) {
String v = tag.getAttribute("xpath");
if(v!=null)
fields.add( parseField(v) );
else {
reader.reportError(reader.ERR_MISSING_ATTRIBUTE, "field", "xpath" );
// recover by ignoring this field.
}
return new ChildlessState();
}
return null;
}
protected void endSelf() {
createIdentityConstraint();
super.endSelf();
}
protected void createIdentityConstraint() {
final XMLSchemaReader reader = (XMLSchemaReader)this.reader;
IdentityConstraint id;
String name = startTag.getAttribute("name");
if(name==null) {
reader.reportError( reader.ERR_MISSING_ATTRIBUTE,
startTag.localName, "name" );
return; // recover by ignoring this constraint.
}
Field[] fs = (Field[])fields.toArray( new Field[fields.size()] );
if( startTag.localName.equals("key") )
id = new KeyConstraint( reader.currentSchema.targetNamespace, name, selector, fs );
else
if( startTag.localName.equals("unique") )
id = new UniqueConstraint( reader.currentSchema.targetNamespace, name, selector, fs );
else
if( startTag.localName.equals("keyref") ) {
final String refer = startTag.getAttribute("refer");
if(refer==null) {
reader.reportError( reader.ERR_MISSING_ATTRIBUTE,
startTag.localName, "refer" );
return; // recover by ignoring this constraint.
}
final String[] qn = reader.splitQName(refer);
if(qn==null) {
reader.reportError( reader.ERR_UNDECLARED_PREFIX, qn );
return;
}
final KeyRefConstraint keyRef =
new KeyRefConstraint( reader.currentSchema.targetNamespace, name, selector, fs );
id = keyRef;
// back patch "key" field of KeyRefConstraint.
reader.addBackPatchJob( new GrammarReader.BackPatch(){
public State getOwnerState() { return IdentityConstraintState.this; }
public void patch() {
XMLSchemaSchema s = reader.grammar.getByNamespace(qn[0]);
if(s==null) {
reader.reportError( reader.ERR_UNDEFINED_SCHEMA, qn[0] );
return;
}
IdentityConstraint idc = s.identityConstraints.get(qn[1]);
if(idc==null) {
reader.reportError( reader.ERR_UNDEFINED_KEY, refer );
return;
}
if(!(idc instanceof KeyConstraint )) {
reader.reportError( reader.ERR_KEYREF_REFERRING_NON_KEY, refer );
return;
}
if( idc.fields.length != keyRef.fields.length ) {
reader.reportError(
new Locator[]{
getLocation(),
reader.getDeclaredLocationOf(idc) },
reader.ERR_KEY_FIELD_NUMBER_MISMATCH,
new Object[]{
idc.localName,
new Integer(idc.fields.length),
keyRef.localName,
new Integer(keyRef.fields.length) } );
return;
}
keyRef.key = (KeyConstraint)idc;
}
});
} else
// this state can be used only when local name is "key","keyref", or "unique".
throw new Error();
if( reader.currentSchema.identityConstraints.get(name)!=null ) {
reader.reportError(
new Locator[]{ this.location, reader.getDeclaredLocationOf(id) },
reader.ERR_DUPLICATE_IDENTITY_CONSTRAINT_DEFINITION,
new Object[]{name} );
} else {
reader.currentSchema.identityConstraints.add(name,id);
}
reader.setDeclaredLocationOf(id);
((ElementDeclState)parentState).onIdentityConstraint(id);
}
protected XPath[] parseSelector( String xpath ) {
final Vector pathObjs = new Vector();
// split to A|B|C
StringTokenizer paths = new StringTokenizer(xpath,"|");
while(paths.hasMoreTokens()) {
XPath pathObj = new XPath();
pathObjs.add(pathObj);
if(!parsePath(pathObj,paths.nextToken(),false))
return new XPath[0];
}
return (XPath[])pathObjs.toArray(new XPath[pathObjs.size()]);
}
protected Field parseField( String xpath ) {
final Vector pathObjs = new Vector();
Field field = new Field();
// split to A|B|C
StringTokenizer paths = new StringTokenizer(xpath,"|");
while(paths.hasMoreTokens()) {
XPath pathObj = new XPath();
pathObjs.add(pathObj);
if(!parsePath(pathObj,paths.nextToken(),true))
return new Field(); // recover by retuning a dummy field.
}
field.paths = (XPath[])pathObjs.toArray(new XPath[pathObjs.size()]);
return field;
}
/**
* parses "aa/bb/cc/.../".
*
* @return true if it succeeds in parsing. Otherwise false.
*/
protected boolean parsePath( XPath pathObj, String xpath, boolean parseField ) {
final Vector stepObjs = new Vector();
if(xpath.startsWith(".//")) {
pathObj.isAnyDescendant = true;
xpath = xpath.substring(3);
}
// split to X/Y/Z
StringTokenizer steps = new StringTokenizer(xpath,"/");
stepObjs.clear();
while(steps.hasMoreTokens()) {
String step = steps.nextToken();
if( step.equals(".") ) continue;
if( step.equals("*") ) {
stepObjs.add( AnyNameClass.theInstance );
continue;
}
boolean attribute = false;
if( step.charAt(0)=='@' && parseField && !steps.hasMoreTokens()) {
// attribute step is allowed only when parsing a field XPath
// and as the last token.
attribute = true;
step = step.substring(1);
} // otherwise the following statement will fail to parse this token.
// resolve QName.
String[] qn = reader.splitQName(step);
if(qn==null) {
// failed to resolve QName properly
reader.reportError( XMLSchemaReader.ERR_BAD_XPATH, step );
return false;
}
if( attribute && step.indexOf(':')<0 )
qn[0] = ""; // if this is an attribute and step is NCName,
// then its namespace URI is "", rather than the
// default namespace.
NameClass nc;
// TODO: NCName test.
if( qn[1].equals("*") ) nc = new NamespaceNameClass(qn[0]);
else nc = new SimpleNameClass(qn[0],qn[1]);
if( attribute==true ) pathObj.attributeStep = nc;
else stepObjs.add(nc);
}
pathObj.steps = (NameClass[])stepObjs.toArray(new NameClass[stepObjs.size()]);
return true;
}
}