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Lucene example source code file (PayloadHelper.java)

This example Lucene source code file (PayloadHelper.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Lucene tags/keywords

payloadhelper, payloadhelper

The Lucene PayloadHelper.java source code

package org.apache.lucene.analysis.payloads;
/**
 * 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.
 */


/**
 * Utility methods for encoding payloads.
 *
 **/
public class PayloadHelper {

  public static byte[] encodeFloat(float payload) {
    return encodeFloat(payload, new byte[4], 0);
  }

  public static byte[] encodeFloat(float payload, byte[] data, int offset){
    return encodeInt(Float.floatToIntBits(payload), data, offset);
  }

  public static byte[] encodeInt(int payload){
    return encodeInt(payload, new byte[4], 0);
  }

  public static byte[] encodeInt(int payload, byte[] data, int offset){
    data[offset] = (byte)(payload >> 24);
    data[offset + 1] = (byte)(payload >> 16);
    data[offset + 2] = (byte)(payload >>  8);
    data[offset + 3] = (byte) payload;
    return data;
  }

  /**
   * @param bytes
   * @see #decodeFloat(byte[], int)
   * @see #encodeFloat(float)
   * @return the decoded float
   */
  public static float decodeFloat(byte [] bytes){
    return decodeFloat(bytes, 0);
  }

  /**
   * Decode the payload that was encoded using {@link #encodeFloat(float)}.
   * NOTE: the length of the array must be at least offset + 4 long.
   * @param bytes The bytes to decode
   * @param offset The offset into the array.
   * @return The float that was encoded
   *
   * @see #encodeFloat(float)
   */
  public static final float decodeFloat(byte [] bytes, int offset){

    return Float.intBitsToFloat(decodeInt(bytes, offset));
  }

  public static final int decodeInt(byte [] bytes, int offset){
    return ((bytes[offset] & 0xFF) << 24) | ((bytes[offset + 1] & 0xFF) << 16)
         | ((bytes[offset + 2] & 0xFF) <<  8) |  (bytes[offset + 3] & 0xFF);
  }
}

Other Lucene examples (source code examples)

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