/**
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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 org.apache.hadoop.hbase.procedure2.util;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.classification.InterfaceStability;
  
  @InterfaceAudience.Private
  @InterfaceStability.Evolving
  public final class StringUtils {
    private StringUtils() {}
  
    public static String humanTimeDiff(long timeDiff) {
      if (timeDiff < 1000) {
        return String.format("%d msec", timeDiff);
      }
  
      StringBuilder buf = new StringBuilder();
      long hours = timeDiff / (60*60*1000);
      long rem = (timeDiff % (60*60*1000));
      long minutes =  rem / (60*1000);
      rem = rem % (60*1000);
      float seconds = rem / 1000.0f;
  
      if (hours != 0){
        buf.append(hours);
        buf.append(" hrs, ");
      }
      if (minutes != 0){
        buf.append(minutes);
        buf.append(" mins, ");
      }
      if (hours > 0 || minutes > 0) {
        buf.append(seconds);
        buf.append(" sec");
      } else {
        buf.append(String.format("%.4f sec", seconds));
      }
      return buf.toString();
    }
  
    public static String humanSize(double size) {
      if (size >= (1L << 40)) {
        return String.format("%.1f T", size / (1L << 40));
      }
  
      if (size >= (1L << 30)) {
        return String.format("%.1f G", size / (1L << 30));
      }
  
      if (size >= (1L << 20)) {
        return String.format("%.1f M", size / (1L << 20));
      }
  
      if (size >= (1L << 10)) {
        return String.format("%.1f K", size / (1L << 10));
      }
  
      return String.format("%.0f", size);
    }
  
    public static boolean isEmpty(final String input) {
      return input == null || input.length() == 0;
    }
  
    public static String buildString(final String... parts) {
      StringBuilder sb = new StringBuilder();
      for (int i = 0; i < parts.length; ++i) {
        sb.append(parts[i]);
      }
      return sb.toString();
    }
  
    public static StringBuilder appendStrings(final StringBuilder sb, final String... parts) {
      for (int i = 0; i < parts.length; ++i) {
        sb.append(parts[i]);
      }
      return sb;
    }
  }