reconcile.hbase.query.ScanColumnQualifiers.java Source code

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Here is the source code for reconcile.hbase.query.ScanColumnQualifiers.java

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/*
 * Copyright (c) 2008, Lawrence Livermore National Security, LLC. Produced at the Lawrence Livermore National
 * Laboratory. Written by David Buttler, buttler1@llnl.gov CODE-400187 All rights reserved. This file is part of
 * RECONCILE
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License (as published by the Free Software Foundation) version 2, dated June 1991. This program is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the terms and conditions of the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA For full text see license.txt
 */
package reconcile.hbase.query;

import java.io.IOException;
import java.util.Map;
import java.util.Set;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.MasterNotRunningException;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;

import com.google.common.collect.Maps;
import com.google.common.collect.Sets;

public class ScanColumnQualifiers {

    private static String table = "example";

    private static Set<String> columnFamily;

    public static void main(String[] args) {
        try {
            if (args.length < 2) {
                System.out.println("Usage: <table> [<column family>]+ ");
                System.out.println("Note: hbase config must be in classpath");
                return;
            }

            // First the setup work
            table = args[0];
            columnFamily = Sets.newHashSet();
            for (int i = 1; i < args.length; i++) {
                columnFamily.add(args[i]);
            }

            Configuration config = HBaseConfiguration.create();
            HBaseAdmin admin = new HBaseAdmin(config);

            if (!admin.tableExists(table.getBytes())) {
                System.out.println("table does not exist: " + table);
                return;
            }

            HTable myTable = new HTable(config, table.getBytes());
            System.out.println("scanning full table:");
            Scan s = new Scan();
            for (String family : columnFamily) {
                s.addFamily(family.getBytes());
            }

            ResultScanner scanner = myTable.getScanner(s);
            printRow(scanner);

            // fin~
        } catch (MasterNotRunningException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    /**
     * Just a generic print function given an iterator. Not necessarily just for printing a single row
     *
     * @param scanner
     * @throws IOException
     */
    @edu.umd.cs.findbugs.annotations.SuppressWarnings(value = "WMI_WRONG_MAP_ITERATOR")
    public static void printRow(ResultScanner scanner) throws IOException {
        Map<String, Long> quals = Maps.newHashMap();
        // iterates through and prints
        int rows = 0;
        for (Result rr = scanner.next(); rr != null; rr = scanner.next()) {
            rows++;
            for (KeyValue kv : rr.list()) {
                String column = new String(kv.getFamily()) + ":" + new String(kv.getQualifier());
                if (!quals.keySet().contains(column)) {
                    System.out.println(column);
                    quals.put(column, 1l);
                } else {
                    quals.put(column, quals.get(column) + 1);
                }
            }
            // print out the row we found and the columns we were looking for

        }

        System.out.println("\n------------------------");
        System.out.println("total rows: " + rows);
        for (String key : quals.keySet()) {
            System.out.println(key + ": " + quals.get(key));
        }
    }

}