ActiveMQ example source code file (BTreeIndexBenchMark.java)

This example ActiveMQ source code file (BTreeIndexBenchMark.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 - ActiveMQ tags/keywords

btreeindex, btreeindex, btreeindexbenchmark, exception, exception, index, indexbenchmark, io, ioexception, long, long, override, override, string, text, transaction

The ActiveMQ BTreeIndexBenchMark.java source code

/**
 * 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.kahadb.index;

import java.io.IOException;
import java.text.NumberFormat;

import org.apache.kahadb.page.Transaction;
import org.apache.kahadb.util.LongMarshaller;
import org.apache.kahadb.util.StringMarshaller;

public class BTreeIndexBenchMark extends IndexBenchmark {

    private NumberFormat nf;

    @Override
    public void setUp() throws Exception {
        super.setUp();
        nf = NumberFormat.getIntegerInstance();
        nf.setMinimumIntegerDigits(10);
        nf.setGroupingUsed(false);
    }
    
    @Override
    protected Index<String, Long> createIndex() throws Exception {

        Transaction tx = pf.tx();
        long id = tx.allocate().getPageId();
        tx.commit();

        BTreeIndex<String, Long> index = new BTreeIndex(pf, id);
        index.setKeyMarshaller(StringMarshaller.INSTANCE);
        index.setValueMarshaller(LongMarshaller.INSTANCE);
        
        return index;
    }
    
    @Override
    protected void dumpIndex(Index<String, Long> index) throws IOException {
        Transaction tx = pf.tx();
        ((BTreeIndex)index).printStructure(tx, System.out);
    }

    /**
     * Overriding so that this generates keys that are the worst case for the BTree. Keys that
     * always insert to the end of the BTree.  
     */
    @Override
    protected String key(long i) {
        return "a-long-message-id-like-key:"+nf.format(i);
    }

}