@Nullable
  @Override
  public ValidationInfo validate() {
    if (myCreateBranch.isSelected()) {
      String branchName = myBranchName.getText().trim();
      if (branchName.isEmpty()) {
        return new ValidationInfo(TaskBundle.message("dialog.message.branch.name.should.not.be.empty"), myBranchName);
      }
      else if (myVcsTaskHandler != null) {
        return myVcsTaskHandler.isBranchNameValid(branchName)
               ? null
               : new ValidationInfo(TaskBundle.message("dialog.message.branch.name.not.valid.check.your.vcs.branch.name.restrictions"), myBranchName);
      }
      else if (branchName.contains(" ")) {
        return new ValidationInfo(TaskBundle.message("dialog.message.branch.name.should.not.contain.spaces"), myBranchName);
      }
      else {
        return null;
      }
    }
    if (myCreateChangelist.isSelected()) {
      if (myChangelistName.getText().trim().isEmpty()) {
        return new ValidationInfo(TaskBundle.message("dialog.message.changelist.name.should.not.be.empty"), myChangelistName);
      }
    }
    return null;
  }
@Nullable
  @Override
  public ValidationInfo validate()