Update buildfile to reflect number of expected conflicts

CupPlugin/src/de/tum/in/www2/cupplugin/views/BuildfileUpdater.java

+package de.tum.in.www2.cupplugin.views;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.parsers.ParserConfigurationException;
+import javax.xml.transform.Result;
+import javax.xml.transform.Source;
+import javax.xml.transform.TransformerConfigurationException;
+import javax.xml.transform.TransformerException;
+import javax.xml.transform.TransformerFactory;
+import javax.xml.transform.TransformerFactoryConfigurationError;
+import javax.xml.transform.dom.DOMSource;
+import javax.xml.transform.stream.StreamResult;
+
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.resources.IProject;
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.Path;
+import org.w3c.dom.*;
+import org.xml.sax.SAXException;
+
+public class BuildfileUpdater {
+	
+	public static void updateExpectedConflicts(IProject project,int number) throws ParserConfigurationException, SAXException, IOException, CoreException, TransformerConfigurationException, TransformerException, TransformerFactoryConfigurationError{
+		boolean modified = false;
+		
+		Path path = new Path("build.xml");
+		IFile file = project.getFile(path);
+		
+		DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
+		DocumentBuilder db = dbf.newDocumentBuilder();
+		Document doc = db.parse(file.getContents());
+		
+		if(doc.getElementsByTagName("cup").getLength() != 1){
+			//TODO: error
+		}
+		else {
+			Node n = doc.getElementsByTagName("cup").item(0);
+			
+			Node expect = n.getAttributes().getNamedItem("expect");
+			
+			if(expect == null){
+				Attr expectedA = doc.createAttribute("expect");
+				n.getAttributes().setNamedItem(expectedA);
+				expect = n.getAttributes().getNamedItem("expect");
+				expect.setTextContent(String.valueOf(number));
+				modified = true;
+			}
+			else if(!expect.getTextContent().equals(String.valueOf(number))){
+				expect.setTextContent(String.valueOf(number));
+				modified = true;
+			}
+		}
+		
+		if(modified){
+			ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+			Source xmlSource = new DOMSource(doc);
+			Result outputTarget = new StreamResult(outputStream);
+			TransformerFactory.newInstance().newTransformer().transform(xmlSource, outputTarget);
+			InputStream is = new ByteArrayInputStream(outputStream.toByteArray());
+			
+			file.setContents(is,true,true,null);
+			is.close();
+		}
+	}
+
+}

CupPlugin/src/de/tum/in/www2/cupplugin/views/CupConflictsView.java

 package de.tum.in.www2.cupplugin.views;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.List;
 
+import javax.xml.parsers.ParserConfigurationException;
+import javax.xml.transform.TransformerException;
+import javax.xml.transform.TransformerFactoryConfigurationError;
+
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.resources.IProject;
+import org.eclipse.core.runtime.CoreException;
 import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.swt.SWT;
@@ -26,6 +34,8 @@ import org.eclipse.swt.widgets.Label;
 import org.eclipse.swt.widgets.Listener;
 import org.eclipse.swt.widgets.MessageBox;
 import org.eclipse.swt.widgets.Shell;
+import org.eclipse.ui.IFileEditorInput;
+import org.xml.sax.SAXException;
 
 import de.in.tum.www2.cup.Conflict;
 import de.in.tum.www2.cup.ConflictResolutionManager;
@@ -124,7 +134,7 @@ public class CupConflictsView extends FailableView implements ICupEditorPageVisi
 	
 	public CupConflictsView(Composite realParent, Jumper jumper,CupTextEditor editor) {
 		super(realParent);
-
+		
 		Composite parent = getMain();
 		
 		this.editor = editor;
@@ -200,7 +210,23 @@ public class CupConflictsView extends FailableView implements ICupEditorPageVisi
 		refreshScrolledLayout();
 	}
 
+	private void updateBuildfile(){
+		//DEBUG
+		try {
+			IFileEditorInput input = (IFileEditorInput)editor.getEditorInput();
+			IFile file = input.getFile();
+			IProject project = file.getProject();
+			
+			BuildfileUpdater.updateExpectedConflicts(project,42);
+		} catch (ParserConfigurationException | SAXException | IOException | CoreException | TransformerException
+				| TransformerFactoryConfigurationError e1) {
+			// TODO Auto-generated catch block
+			e1.printStackTrace();
+		}
+	}
+	
 	private void updateConflicts(ConflictResolutionManager crm) {
+		updateBuildfile();
 		ignoreRRAfterLine = computeIgnoreRRAfter();
 		
 		List<Conflict> conflicts = new ArrayList<>();