Program: 141736
Project: 141736
Buggy source:
/** 
 * @see org.eclipse.jface.wizard.Wizard#performFinish()
 */
@Override public boolean performFinish(){
  property.setId(repositoryFactory.getNextId());
  property.setLabel(property.getDisplayName());
  URL url=mainPage.getUrl();
  Path p=new Path(property.getLabel());
  String itemName=p.removeFileExtension().lastSegment();
  String fileExtension=null;
  if (url != null) {
    p=new Path(url.getPath());
    if (p.getFileExtension() != null) {
      fileExtension=p.getFileExtension();
    }
  }
 else {
    fileExtension=p.getFileExtension();
  }
  if (fileExtension == null || fileExtension.isEmpty()) {
    fileExtension="String_Node_Str";
  }
  if (fileExtension.equals(FileConstants.ITEM_EXTENSION)) {
    fileExtension+="String_Node_Str";
  }
  if (fileExtension.equals(FileConstants.PROPERTIES_EXTENSION)) {
    fileExtension+="String_Node_Str";
  }
  ByteArray byteArray=PropertiesFactory.eINSTANCE.createByteArray();
  StringBuffer sb=new StringBuffer();
  if (url == null) {
    byteArray.setInnerContent(new byte[0]);
  }
 else {
    try {
      InputStream inputStream=url.openStream();
      BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(inputStream,"String_Node_Str"));
      String line=bufferedReader.readLine();
      while (line != null) {
        sb.append(line).append(System.getProperty("String_Node_Str"));
        line=bufferedReader.readLine();
      }
      byteArray.setInnerContent(sb.toString().getBytes());
    }
 catch (    Exception e) {
      MessageBoxExceptionHandler.process(e);
      ExceptionHandler.process(e);
      return false;
    }
  }
  ReferenceFileItem refItem=PropertiesFactory.eINSTANCE.createReferenceFileItem();
  refItem.setContent(byteArray);
  refItem.setExtension(fileExtension);
  refItem.setName(itemName);
  item.setName(itemName);
  item.setBindingExtension(fileExtension);
  byteArray=PropertiesFactory.eINSTANCE.createByteArray();
  byteArray.setInnerContent(new byte[0]);
  item.setContent(byteArray);
  item.getReferenceResources().add(refItem);
  RepositoryWorkUnit<Object> workUnit=new RepositoryWorkUnit<Object>(this.getWindowTitle(),this){
    @Override protected void run() throws LoginException, PersistenceException {
      repositoryFactory.create(item,mainPage.getDestinationPath());
      RelationshipItemBuilder.getInstance().addOrUpdateItem(item);
    }
  }
;
  workUnit.setAvoidUnloadResources(true);
  repositoryFactory.executeRepositoryWorkUnit(workUnit);
  return item != null;
}

Fixed version (ground truth):
/** 
 * @see org.eclipse.jface.wizard.Wizard#performFinish()
 */
@Override public boolean performFinish(){
  property.setId(repositoryFactory.getNextId());
  property.setLabel(property.getDisplayName());
  URL url=mainPage.getUrl();
  Path p=new Path(property.getLabel());
  String itemName=p.removeFileExtension().lastSegment();
  String fileExtension=null;
  if (url != null) {
    p=new Path(url.getPath());
    if (p.getFileExtension() != null) {
      fileExtension=p.getFileExtension();
    }
  }
 else {
    fileExtension=p.getFileExtension();
  }
  if (fileExtension == null || fileExtension.isEmpty()) {
    fileExtension="String_Node_Str";
  }
  if (fileExtension.equals(FileConstants.ITEM_EXTENSION)) {
    fileExtension+="String_Node_Str";
  }
  if (fileExtension.equals(FileConstants.PROPERTIES_EXTENSION)) {
    fileExtension+="String_Node_Str";
  }
  ByteArray byteArray=PropertiesFactory.eINSTANCE.createByteArray();
  StringBuffer sb=new StringBuffer();
  if (url == null) {
    byteArray.setInnerContent(new byte[0]);
  }
 else {
    try {
      InputStream inputStream=url.openStream();
      BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(inputStream,"String_Node_Str"));
      String line=bufferedReader.readLine();
      while (line != null) {
        sb.append(line).append(System.getProperty("String_Node_Str"));
        line=bufferedReader.readLine();
      }
      byteArray.setInnerContent(sb.toString().getBytes());
    }
 catch (    Exception e) {
      MessageBoxExceptionHandler.process(e);
      ExceptionHandler.process(e);
      return false;
    }
  }
  ReferenceFileItem refItem=PropertiesFactory.eINSTANCE.createReferenceFileItem();
  refItem.setContent(byteArray);
  refItem.setExtension(fileExtension);
  refItem.setName(itemName);
  item.setName(itemName);
  item.setBindingExtension(fileExtension);
  byteArray=PropertiesFactory.eINSTANCE.createByteArray();
  byteArray.setInnerContent(new byte[0]);
  item.setContent(byteArray);
  item.getReferenceResources().add(refItem);
  RepositoryWorkUnit<Object> workUnit=new RepositoryWorkUnit<Object>(this.getWindowTitle(),this){
    @Override protected void run() throws LoginException, PersistenceException {
      repositoryFactory.create(item,mainPage.getDestinationPath());
      RelationshipItemBuilder.getInstance().addOrUpdateItem(item);
    }
  }
;
  workUnit.setAvoidUnloadResources(true);
  repositoryFactory.executeRepositoryWorkUnit(workUnit);
  return true;
}