java/com/google/gerrit/server/submit/CircularPathFinder.java

// Copyright (C) 2020 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.google.gerrit.server.submit;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;

class CircularPathFinder {
  private CircularPathFinder() {}

  /**
   * Prints a circular path according to the nodes in {@code p} and the start node {@code target}.
   */
  public static <T> String printCircularPath(Collection<T> p, T target) {
    StringBuilder sb = new StringBuilder();
    sb.append(target);
    ArrayList<T> reverseP = new ArrayList<>(p);
    Collections.reverse(reverseP);
    for (T t : reverseP) {
      sb.append("->");
      sb.append(t);
      if (t.equals(target)) {
        break;
      }
    }
    return sb.toString();
  }
}