Lucene example source code file (NewAnalyzerTask.java)

This example Lucene source code file (NewAnalyzerTask.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

analyzer, analyzer, arraylist, class, constructor, exception, io, ioexception, newanalyzertask, override, override, reflection, string, string, stringtokenizer, stringtokenizer, util

The Lucene NewAnalyzerTask.java source code

package org.apache.lucene.benchmark.byTask.tasks;
/**
 * Copyright 2005 The Apache Software Foundation
 *
 * 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.
 */

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.benchmark.byTask.PerfRunData;
import org.apache.lucene.util.Version;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;
import java.lang.reflect.Constructor;

/**
 * Create a new {@link org.apache.lucene.analysis.Analyzer} and set it it in the getRunData() for use by all future tasks.
 *
 */
public class NewAnalyzerTask extends PerfTask {
  private List<String> analyzerClassNames;
  private int current;

  public NewAnalyzerTask(PerfRunData runData) {
    super(runData);
    analyzerClassNames = new ArrayList<String>();
  }
  
  public static final Analyzer createAnalyzer(String className) throws Exception{
    final Class<? extends Analyzer> clazz = Class.forName(className).asSubclass(Analyzer.class);
    try {
      // first try to use a ctor with version parameter (needed for many new Analyzers that have no default one anymore
      Constructor<? extends Analyzer> cnstr = clazz.getConstructor(Version.class);
      return cnstr.newInstance(Version.LUCENE_CURRENT);
    } catch (NoSuchMethodException nsme) {
      // otherwise use default ctor
      return clazz.newInstance();
    }
  }

  @Override
  public int doLogic() throws IOException {
    String className = null;
    try {
      if (current >= analyzerClassNames.size())
      {
        current = 0;
      }
      className = analyzerClassNames.get(current++);
      if (className == null || className.equals(""))
      {
        className = "org.apache.lucene.analysis.standard.StandardAnalyzer"; 
      }
      if (className.indexOf(".") == -1  || className.startsWith("standard."))//there is no package name, assume o.a.l.analysis
      {
        className = "org.apache.lucene.analysis." + className;
      }
      getRunData().setAnalyzer(createAnalyzer(className));
      System.out.println("Changed Analyzer to: " + className);
    } catch (Exception e) {
      throw new RuntimeException("Error creating Analyzer: " + className, e);
    }
    return 1;
  }

  /**
   * Set the params (analyzerClassName only),  Comma-separate list of Analyzer class names.  If the Analyzer lives in
   * org.apache.lucene.analysis, the name can be shortened by dropping the o.a.l.a part of the Fully Qualified Class Name.
   * <p/>
   * Example Declaration: {"NewAnalyzer" NewAnalyzer(WhitespaceAnalyzer, SimpleAnalyzer, StopAnalyzer, standard.StandardAnalyzer) >
   * @param params analyzerClassName, or empty for the StandardAnalyzer
   */
  @Override
  public void setParams(String params) {
    super.setParams(params);
    for (StringTokenizer tokenizer = new StringTokenizer(params, ","); tokenizer.hasMoreTokens();) {
      String s = tokenizer.nextToken();
      analyzerClassNames.add(s.trim());
    }
  }

  /* (non-Javadoc)
   * @see org.apache.lucene.benchmark.byTask.tasks.PerfTask#supportsParams()
   */
  @Override
  public boolean supportsParams() {
    return true;
  }
}