Compares two floats for order. : Float « Data Type « Java Tutorial

1. Java Tutorial
2. Data Type
3. Float

import java.math.BigDecimal;
import java.math.BigInteger;

/**
 * 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.
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/**
 * Provides extra functionality for Java Number classes.
 *
 * @author <a href="mailto:rand_mcneely@yahoo.com">Rand McNeely</a>
 * @author Stephen Colebourne
 * @author <a href="mailto:steve.downey@netfolio.com">Steve Downey</a>
 * @author Eric Pugh
 * @author Phil Steitz
 * @since 1.0
 * @version $Id: NumberUtils.java 488819 2006-12-19 21:50:04Z bayard $
 * 
 */
public class Main {








  
  /**
   * Compares two floats for order.
   *
   * This method is more comprehensive than the standard Java greater than,
   * less than and equals operators.
   * <ul>
   *  <li>It returns <code>-1</code> if the first value is less than the second.
   *  <li>It returns <code>+1</code> if the first value is greater than the second.
   *  <li>It returns <code>0</code> if the values are equal.
   * </ul>
   *
   *  The ordering is as follows, largest to smallest:
   * <ul>
   * <li>NaN
   * <li>Positive infinity
   * <li>Maximum float
   * <li>Normal positive numbers
   * <li>+0.0
   * <li>-0.0
   * <li>Normal negative numbers
   * <li>Minimum float (-Float.MAX_VALUE)
   * <li>Negative infinity
   * </ul>
   *
   * Comparing <code>NaN</code> with <code>NaN</code> will return
   * <code>0</code>.
   * 
   * @param lhs  the first <code>float</code>
   * @param rhs  the second <code>float</code>
   * @return <code>-1</code> if lhs is less, <code>+1</code> if greater,
   *  <code>0</code> if equal to rhs
   */
  public static int compare(float lhs, float rhs) {
      if (lhs < rhs) {
          return -1;
      }
      if (lhs > rhs) {
          return +1;
      }
      //Need to compare bits to handle 0.0 == -0.0 being true
      // compare should put -0.0 < +0.0
      // Two NaNs are also == for compare purposes
      // where NaN == NaN is false
      int lhsBits = Float.floatToIntBits(lhs);
      int rhsBits = Float.floatToIntBits(rhs);
      if (lhsBits == rhsBits) {
          return 0;
      }
      //Something exotic! A comparison to NaN or 0.0 vs -0.0
      //Fortunately NaN's int is > than everything else
      //Also negzeros bits < poszero
      //NAN: 2143289344
      //MAX: 2139095039
      //NEGZERO: -2147483648
      if (lhsBits < rhsBits) {
          return -1;
      } else {
          return +1;
      }
  }
}