/**
* Copyright (c) 2013, Institute of Information Systems (Sven Groppe and contributors of LUPOSDATE), University of Luebeck
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this list of conditions and the following
* disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other materials provided with the distribution.
* - Neither the name of the University of Luebeck nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package lupos.gui.operatorgraph.visualeditor.queryeditor.util;
import java.util.HashSet;
import lupos.gui.operatorgraph.GraphWrapperIDTuple;
import lupos.gui.operatorgraph.graphwrapper.GraphWrapper;
import lupos.gui.operatorgraph.visualeditor.VisualEditor;
import lupos.gui.operatorgraph.visualeditor.operators.Operator;
import lupos.gui.operatorgraph.visualeditor.queryeditor.operators.Construct;
import lupos.gui.operatorgraph.visualeditor.queryeditor.operators.ConstructTemplateContainer;
import lupos.gui.operatorgraph.visualeditor.queryeditor.operators.RetrieveData;
import lupos.gui.operatorgraph.visualeditor.util.Connection;
public class QueryConnection extends Connection<Operator> {
public QueryConnection(VisualEditor<Operator> visualEditor) {
super(visualEditor);
}
protected String validateConnection() {
String errorString = "";
// we can't connect two operators on different layers...
if(((Operator) this.firstOp.getElement()).getParentContainer() != ((Operator) this.secondOp.getElement()).getParentContainer()) {
errorString = "You can only connect two operators in the same layer!";
}
if(this.secondOp.getElement() instanceof ConstructTemplateContainer && !(this.firstOp.getElement() instanceof Construct)) {
errorString = "A ConstructTemplateContainer can only be a child of a CONSTRUCT operator!";
}
if(this.secondOp.getElement() instanceof RetrieveData) {
errorString = "RetrieveData operators (ASK, CONSTRUCT, DESCRIBE, SELECT) can't have preceeding elements!";
}
if(((Operator) this.firstOp.getElement()).getParentContainer() == null) {
this.firstOp.addSucceedingElement(new GraphWrapperIDTuple(this.secondOp, 0));
if(this.hasCircle(this.firstOp, new HashSet<GraphWrapper>())) {
errorString = "Circles are not allowed outside a Container!";
}
this.firstOp.removeSucceedingElement(this.secondOp);
}
return errorString;
}
private boolean hasCircle(GraphWrapper operator, HashSet<GraphWrapper> visited) {
if(visited.contains(operator)) {
return true;
}
visited.add(operator);
for(GraphWrapperIDTuple opidt : operator.getSucceedingElements()) {
if(this.hasCircle(opidt.getOperator(), visited) == true) {
return true;
}
}
return false;
}
}