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Lucene example source code file (FieldInfo.java)

This example Lucene source code file (FieldInfo.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

fieldinfo, fieldinfo, object, object, override, override, string, string

The Lucene FieldInfo.java source code

package org.apache.lucene.index;

/**
 * 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.
 */

final class FieldInfo {
  final String name;
  final int number;

  boolean isIndexed;

  // true if term vector for this field should be stored
  boolean storeTermVector;
  boolean storeOffsetWithTermVector;
  boolean storePositionWithTermVector;

  boolean omitNorms; // omit norms associated with indexed fields  
  boolean omitTermFreqAndPositions;
  
  boolean storePayloads; // whether this field stores payloads together with term positions

  FieldInfo(String na, boolean tk, int nu, boolean storeTermVector, 
            boolean storePositionWithTermVector,  boolean storeOffsetWithTermVector, 
            boolean omitNorms, boolean storePayloads, boolean omitTermFreqAndPositions) {
    name = na;
    isIndexed = tk;
    number = nu;
    if (isIndexed) {
      this.storeTermVector = storeTermVector;
      this.storeOffsetWithTermVector = storeOffsetWithTermVector;
      this.storePositionWithTermVector = storePositionWithTermVector;
      this.storePayloads = storePayloads;
      this.omitNorms = omitNorms;
      this.omitTermFreqAndPositions = omitTermFreqAndPositions;
    } else { // for non-indexed fields, leave defaults
      this.storeTermVector = false;
      this.storeOffsetWithTermVector = false;
      this.storePositionWithTermVector = false;
      this.storePayloads = false;
      this.omitNorms = true;
      this.omitTermFreqAndPositions = false;
    }
    assert !omitTermFreqAndPositions || !storePayloads;
  }

  @Override
  public Object clone() {
    return new FieldInfo(name, isIndexed, number, storeTermVector, storePositionWithTermVector,
                         storeOffsetWithTermVector, omitNorms, storePayloads, omitTermFreqAndPositions);
  }

  void update(boolean isIndexed, boolean storeTermVector, boolean storePositionWithTermVector, 
              boolean storeOffsetWithTermVector, boolean omitNorms, boolean storePayloads, boolean omitTermFreqAndPositions) {

    if (this.isIndexed != isIndexed) {
      this.isIndexed = true;                      // once indexed, always index
    }
    if (isIndexed) { // if updated field data is not for indexing, leave the updates out
      if (this.storeTermVector != storeTermVector) {
        this.storeTermVector = true;                // once vector, always vector
      }
      if (this.storePositionWithTermVector != storePositionWithTermVector) {
        this.storePositionWithTermVector = true;                // once vector, always vector
      }
      if (this.storeOffsetWithTermVector != storeOffsetWithTermVector) {
        this.storeOffsetWithTermVector = true;                // once vector, always vector
      }
      if (this.storePayloads != storePayloads) {
        this.storePayloads = true;
      }
      if (this.omitNorms != omitNorms) {
        this.omitNorms = false;                // once norms are stored, always store
      }
      if (this.omitTermFreqAndPositions != omitTermFreqAndPositions) {
        this.omitTermFreqAndPositions = true;                // if one require omitTermFreqAndPositions at least once, it remains off for life
        this.storePayloads = false;
      }
    }
    assert !this.omitTermFreqAndPositions || !this.storePayloads;
  }
}

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