Program: 47165
Project: 47165
Buggy source:
public void build(){
  JPanel checkPanel=new JPanel();
  checkPanel.applyComponentOrientation(ComponentOrientation.getOrientation(new Locale(configuration.getLanguage())));
  add(checkPanel,BorderLayout.LINE_START);
  allRenderers=new DefaultMutableTreeNode(Messages.getString("String_Node_Str"));
  DefaultMutableTreeNode renderersGroup=null;
  String lastGroup=null;
  String groupName;
  boolean firstLoop=true;
  for (  String renderer : RendererConfiguration.getAllRenderersNames()) {
    if (lastGroup != null && renderer.startsWith(lastGroup)) {
      if (renderer.indexOf("String_Node_Str") > 0) {
        renderersGroup.add(new DefaultMutableTreeNode(renderer.substring(renderer.indexOf("String_Node_Str"))));
      }
 else {
        renderersGroup.add(new DefaultMutableTreeNode(renderer));
      }
    }
 else {
      if (!firstLoop) {
        allRenderers.add(renderersGroup);
      }
      if (renderer.indexOf("String_Node_Str") > 0) {
        groupName=renderer.substring(0,renderer.indexOf("String_Node_Str"));
        renderersGroup=new DefaultMutableTreeNode(groupName);
        renderersGroup.add(new DefaultMutableTreeNode(renderer.substring(renderer.indexOf("String_Node_Str"))));
      }
 else {
        groupName=renderer;
        renderersGroup=new DefaultMutableTreeNode(groupName);
      }
      lastGroup=groupName;
      firstLoop=false;
    }
  }
  SrvTree=new JTree(new DefaultTreeModel(allRenderers));
  checkTreeManager=new CheckTreeManager(SrvTree);
  checkPanel.add(new JScrollPane(SrvTree));
  checkPanel.setSize(400,500);
}

Fixed version (ground truth):
public void build(){
  JPanel checkPanel=new JPanel();
  checkPanel.applyComponentOrientation(ComponentOrientation.getOrientation(new Locale(configuration.getLanguage())));
  add(checkPanel,BorderLayout.LINE_START);
  allRenderers=new DefaultMutableTreeNode(Messages.getString("String_Node_Str"));
  DefaultMutableTreeNode renderersGroup=null;
  String lastGroup=null;
  String groupName;
  boolean firstLoop=true;
  for (  String renderer : RendererConfiguration.getAllRenderersNames()) {
    if (lastGroup != null && renderer.startsWith(lastGroup)) {
      if (renderer.indexOf("String_Node_Str") > 0) {
        renderersGroup.add(new DefaultMutableTreeNode(renderer.substring(renderer.indexOf("String_Node_Str"))));
      }
 else {
        renderersGroup.add(new DefaultMutableTreeNode(renderer));
      }
    }
 else {
      if (!firstLoop) {
        allRenderers.add(renderersGroup);
      }
      if (renderer.indexOf("String_Node_Str") > 0) {
        groupName=renderer.substring(0,renderer.indexOf("String_Node_Str"));
        renderersGroup=new DefaultMutableTreeNode(groupName);
        renderersGroup.add(new DefaultMutableTreeNode(renderer.substring(renderer.indexOf("String_Node_Str"))));
      }
 else {
        groupName=renderer;
        renderersGroup=new DefaultMutableTreeNode(groupName);
      }
      lastGroup=groupName;
      firstLoop=false;
    }
  }
  if (renderersGroup != null) {
    allRenderers.add(renderersGroup);
  }
  SrvTree=new JTree(new DefaultTreeModel(allRenderers));
  checkTreeManager=new CheckTreeManager(SrvTree);
  checkPanel.add(new JScrollPane(SrvTree));
  checkPanel.setSize(400,500);
}