MockFixedLengthPayloadFilter.java

/*
 * 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.lucene.analysis;

import java.io.IOException;
import java.util.Random;

import org.apache.lucene.analysis.tokenattributes.PayloadAttribute;
import org.apache.lucene.util.BytesRef;

/**
 * TokenFilter that adds random fixed-length payloads.
 */
public final class MockFixedLengthPayloadFilter extends TokenFilter {
  private final PayloadAttribute payloadAtt = addAttribute(PayloadAttribute.class);
  private final Random random;
  private final byte[] bytes;
  private final BytesRef payload;

  public MockFixedLengthPayloadFilter(Random random, TokenStream in, int length) {
    super(in);
    if (length < 0) {
      throw new IllegalArgumentException("length must be >= 0");
    }
    this.random = random;
    this.bytes = new byte[length];
    this.payload = new BytesRef(bytes);
  }

  @Override
  public boolean incrementToken() throws IOException {
    if (input.incrementToken()) {
      random.nextBytes(bytes);
      payloadAtt.setPayload(payload);
      return true;
    } else {
      return false;
    }
  }
}