/*
* Copyright (C) NetStruxr, Inc. All rights reserved.
*
* This software is published under the terms of the NetStruxr
* Public Software License version 0.5, a copy of which has been
* included with this distribution in the LICENSE.NPL file. */
package er.directtoweb.qualifiers;
import java.util.Enumeration;
import org.apache.log4j.Logger;
import com.webobjects.directtoweb.BooleanQualifier;
import com.webobjects.directtoweb.NonNullQualifier;
import com.webobjects.eocontrol.EOAndQualifier;
import com.webobjects.eocontrol.EOKeyComparisonQualifier;
import com.webobjects.eocontrol.EOKeyValueQualifier;
import com.webobjects.eocontrol.EONotQualifier;
import com.webobjects.eocontrol.EOOrQualifier;
import com.webobjects.eocontrol.EOQualifierEvaluation;
/**
* Contains a single method for traversing
* a network of qualifiers.
*/
public class ERDQualifierTraversal {
/** logging support */
public static final Logger log = Logger.getLogger(ERDQualifierTraversal.class);
/**
* Simple method to traverse a network of qualifiers
* using a callback.
* @param q qualifier to traverse
* @param cb call back
* @return if the traversal was successful
*/
public static boolean traverseQualifier(EOQualifierEvaluation q, ERDQualifierTraversalCallback cb) {
Boolean result=null;
if (q==null)
result=Boolean.TRUE;
else {
if (q instanceof EOOrQualifier) {
EOOrQualifier aq=(EOOrQualifier)q;
cb.traverseOrQualifier(aq);
result=Boolean.TRUE;
for (Enumeration e=aq.qualifiers().objectEnumerator(); e.hasMoreElements(); ) {
if (!traverseQualifier((EOQualifierEvaluation)e.nextElement(),cb)) {
result=Boolean.FALSE;
break;
}
}
} else if (q instanceof EOAndQualifier) {
EOAndQualifier aq=(EOAndQualifier)q;
cb.traverseAndQualifier(aq);
result=Boolean.TRUE;
for (Enumeration e=aq.qualifiers().objectEnumerator(); e.hasMoreElements(); ) {
if (!traverseQualifier((EOQualifierEvaluation)e.nextElement(),cb)) {
result=Boolean.FALSE;
break;
}
}
} else if (q instanceof EONotQualifier) {
EONotQualifier nq = (EONotQualifier)q;
cb.traverseNotQualifier((EONotQualifier)q);
result = traverseQualifier(nq.qualifier(),cb) ? Boolean.TRUE : Boolean.FALSE;
} else if (q instanceof EOKeyValueQualifier) {
result=cb.traverseKeyValueQualifier((EOKeyValueQualifier)q) ? Boolean.TRUE : Boolean.FALSE;
} else if (q instanceof EOKeyComparisonQualifier) {
result=cb.traverseKeyComparisonQualifier((EOKeyComparisonQualifier)q) ? Boolean.TRUE : Boolean.FALSE;
} else if (q instanceof BooleanQualifier) {
result=cb.traverseBooleanQualifier((BooleanQualifier)q) ? Boolean.TRUE : Boolean.FALSE;
} else if (q instanceof NonNullQualifier) {
result=cb.traverseNonNullQualifier((NonNullQualifier)q) ? Boolean.TRUE : Boolean.FALSE;
}
}
if (result==null) {
log.error("Found unknown qualifier type:"+q.getClass().getName());
throw new RuntimeException("Found unknown qualifier type:"+q.getClass().getName());
}
return result.booleanValue();
}
}