content: /*
   * 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 org.apache.bookkeeper.tools.perf.utils;
  
  import java.text.DecimalFormat;
  import java.text.DecimalFormatSymbols;
  import java.text.FieldPosition;
  
  /**
   * A decimal format that adds padding zeros.
   */
  public class PaddingDecimalFormat extends DecimalFormat {
      private int minimumLength;
  
      /**
       * Creates a PaddingDecimalFormat using the given pattern and minimum minimumLength and the symbols for the default
       * locale.
       */
      public PaddingDecimalFormat(String pattern, int minLength) {
          super(pattern);
          minimumLength = minLength;
      }
  
      /**
       * Creates a PaddingDecimalFormat using the given pattern, symbols and minimum minimumLength.
       */
      public PaddingDecimalFormat(String pattern, DecimalFormatSymbols symbols, int minLength) {
          super(pattern, symbols);
          minimumLength = minLength;
      }
  
      @Override
      public StringBuffer format(double number, StringBuffer toAppendTo, FieldPosition pos) {
          int initLength = toAppendTo.length();
          super.format(number, toAppendTo, pos);
          return pad(toAppendTo, initLength);
      }
  
      @Override
      public StringBuffer format(long number, StringBuffer toAppendTo, FieldPosition pos) {
          int initLength = toAppendTo.length();
          super.format(number, toAppendTo, pos);
          return pad(toAppendTo, initLength);
      }
  
      private StringBuffer pad(StringBuffer toAppendTo, int initLength) {
          int numLength = toAppendTo.length() - initLength;
          int padLength = minimumLength - numLength;
          if (padLength > 0) {
              StringBuffer pad = new StringBuffer(padLength);
              for (int i = 0; i < padLength; i++) {
                  pad.append(' ');
              }
              toAppendTo.insert(initLength, pad);
          }
          return toAppendTo;
      }
  
      @Override
      public boolean equals(Object obj) {
          if (!(obj instanceof PaddingDecimalFormat)) {
              return false;
          }
  
          PaddingDecimalFormat other = (PaddingDecimalFormat) obj;
          return minimumLength == other.minimumLength && super.equals(obj);
      }
  
      @Override
      public int hashCode() {
          return 31 * super.hashCode() + minimumLength;
      }
  }
  