Program: 133688
Project: 133688
Buggy source:
@Override public void createControl(Composite parent){
  if (parent != null) {
    GridData gridData;
    wizardPageComposite=new Composite(parent,SWT.NONE);
    wizardPageComposite.setLayout(new GridLayout(2,false));
    Label fileLabel=new Label(wizardPageComposite,SWT.NONE);
    fileLabel.setText("String_Node_Str");
    gridData=new GridData(SWT.LEFT,SWT.END,false,false);
    gridData.horizontalSpan=2;
    fileLabel.setLayoutData(gridData);
    final Text fileText=new Text(wizardPageComposite,SWT.NONE | SWT.BORDER);
    fileText.setEditable(false);
    fileText.setLayoutData(new GridData(SWT.FILL,SWT.BEGINNING,true,true));
    Button browseButton=new Button(wizardPageComposite,SWT.NONE);
    browseButton.setLayoutData(new GridData(SWT.RIGHT,SWT.BEGINNING,false,true));
    browseButton.setText("String_Node_Str");
    final Shell shell=parent.getShell();
    browseButton.addSelectionListener(new SelectionAdapter(){
      @Override public void widgetSelected(      SelectionEvent e){
        FileDialog fileDialog=new FileDialog(shell,fileDialogStyle);
        fileDialog.setText("String_Node_Str");
        fileDialog.open();
        selectedFileNames.clear();
        for (        String fileName : fileDialog.getFileNames()) {
          selectedFileNames.add(fileName);
        }
        filterPath=fileDialog.getFilterPath();
        int numFiles=selectedFileNames.size();
        if (numFiles == 1) {
          fileText.setText(filterPath + System.getProperty("String_Node_Str") + selectedFileNames.get(0));
        }
 else         if (numFiles > 1) {
          String text="String_Node_Str" + selectedFileNames.get(0) + "String_Node_Str";
          for (int i=1; i < selectedFileNames.size(); i++) {
            text+="String_Node_Str" + selectedFileNames.get(i) + "String_Node_Str";
          }
          fileText.setText(text);
        }
        setPageComplete(checkSelection());
        return;
      }
    }
);
    setControl(wizardPageComposite);
    setPageComplete(false);
  }
  return;
}

Fixed version (ground truth):
@Override public void createControl(Composite parent){
  if (parent != null) {
    GridData gridData;
    wizardPageComposite=new Composite(parent,SWT.NONE);
    wizardPageComposite.setLayout(new GridLayout(2,false));
    Label fileLabel=new Label(wizardPageComposite,SWT.NONE);
    fileLabel.setText("String_Node_Str");
    gridData=new GridData(SWT.LEFT,SWT.END,false,false);
    gridData.horizontalSpan=2;
    fileLabel.setLayoutData(gridData);
    gridData=new GridData(SWT.FILL,SWT.BEGINNING,true,true);
    gridData.minimumHeight=30;
    final Text fileText=new Text(wizardPageComposite,SWT.NONE | SWT.BORDER);
    fileText.setEditable(false);
    fileText.setLayoutData(gridData);
    gridData=new GridData(SWT.RIGHT,SWT.BEGINNING,false,true);
    gridData.minimumHeight=30;
    Button browseButton=new Button(wizardPageComposite,SWT.NONE);
    browseButton.setLayoutData(gridData);
    browseButton.setText("String_Node_Str");
    final Shell shell=parent.getShell();
    browseButton.addSelectionListener(new SelectionAdapter(){
      @Override public void widgetSelected(      SelectionEvent e){
        FileDialog fileDialog=new FileDialog(shell,fileDialogStyle);
        fileDialog.setText("String_Node_Str");
        fileDialog.open();
        selectedFileNames.clear();
        for (        String fileName : fileDialog.getFileNames()) {
          selectedFileNames.add(fileName);
        }
        filterPath=fileDialog.getFilterPath();
        int numFiles=selectedFileNames.size();
        if (numFiles == 1) {
          fileText.setText(filterPath + System.getProperty("String_Node_Str") + selectedFileNames.get(0));
        }
 else         if (numFiles > 1) {
          String text="String_Node_Str" + selectedFileNames.get(0) + "String_Node_Str";
          for (int i=1; i < selectedFileNames.size(); i++) {
            text+="String_Node_Str" + selectedFileNames.get(i) + "String_Node_Str";
          }
          fileText.setText(text);
        }
        setPageComplete(checkSelection());
        return;
      }
    }
);
    setControl(wizardPageComposite);
    setPageComplete(false);
  }
  return;
}