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* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
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package org.apache.cayenne.modeler.util;
import org.apache.cayenne.map.Attribute;
import org.apache.cayenne.map.DbRelationship;
import org.apache.cayenne.map.Relationship;
public class EntityTreeRelationshipFilter implements EntityTreeFilter {
public boolean attributeMatch(Object node, Attribute attr) {
// attrs not allowed here
return false;
}
public boolean relationshipMatch(Object node, Relationship rel) {
if (!(node instanceof Relationship)) {
return true;
}
/**
* We do not allow A->B->A chains, where relationships are
* to-one
*/
DbRelationship prev = (DbRelationship) node;
return !(!rel.isToMany() && prev.getReverseRelationship() == rel);
}
}