• hbase scan 的例子


    /**
     * Created by han on 2016/1/28.
     */
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.hbase.*;
    import org.apache.hadoop.hbase.client.*;
    import org.apache.hadoop.hbase.filter.CompareFilter.CompareOp;
    import org.apache.hadoop.hbase.filter.Filter;
    import org.apache.hadoop.hbase.filter.FilterList;
    import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
    import org.apache.hadoop.hbase.util.Bytes;
    
    import java.io.IOException;
    import java.util.ArrayList;
    import java.util.List;
    
    public class test {
    
        public static Configuration configuration;
        static {
            configuration = HBaseConfiguration.create();
            configuration.set("hbase.zookeeper.property.clientPort", "2181");
            configuration.set("hbase.zookeeper.quorum", "48.0.191.154:2181,48.0.191.154:2182,48.0.191.154:2183");
            configuration.set("hbase.master", "48.0.191.154:60000");
            System.setProperty("java.library.path","E:\资料\hadoop-2.6.2\bin");
            System.setProperty("hadoop.home.dir", "E:\资料\hadoop-2.6.2");
            System.setProperty("PATH", "E:\资料\hadoop-2.6.2\bin");
    
        }
    
        public static void main(String[] args) {
          //   createTable("h");
          //   insertData("h");
         //   QueryAll("h");
       //     QueryByCondition1("h");
           QueryByCondition2("h");
        //   QueryByCondition3("h");
          //  deleteRow("h","abcdef");
          //  deleteByCondition("h","abcdef");
          //  dropTable("h");
        }
    
        /**
         * 创建表
         * @param tableName
         */
        public static void createTable(String tableName) {
            System.out.println("start create table ......");
            try {
                HBaseAdmin hBaseAdmin = new HBaseAdmin(configuration);
                if (hBaseAdmin.tableExists(tableName)) {// 如果存在要创建的表,那么先删除,再创建
                    hBaseAdmin.disableTable(tableName);
                    hBaseAdmin.deleteTable(tableName);
                    System.out.println(tableName + " is exist,detele....");
                }
                HTableDescriptor tableDescriptor = new HTableDescriptor(tableName);
                tableDescriptor.addFamily(new HColumnDescriptor("column1"));
                tableDescriptor.addFamily(new HColumnDescriptor("column2"));
                tableDescriptor.addFamily(new HColumnDescriptor("column3"));
                tableDescriptor.addFamily(new HColumnDescriptor("cf"));
                hBaseAdmin.createTable(tableDescriptor);
            } catch (MasterNotRunningException e) {
                e.printStackTrace();
            } catch (ZooKeeperConnectionException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            System.out.println("end create table ......");
        }
    
        /**
         * 插入数据
         * @param tableName
         */
        public static void insertData(String tableName) {
            System.out.println("start insert data ......");
            HTablePool pool = new HTablePool(configuration, 1000);
            HTableInterface table =   pool.getTable(tableName);
            Put put = new Put("abcdef".getBytes());// 一个PUT代表一行数据,再NEW一个PUT表示第二行数据,每行一个唯一的ROWKEY,此处rowkey为put构造方法中传入的值
            put.add("column1".getBytes(), null, "aaa".getBytes());// 本行数据的第一列
            put.add("column2".getBytes(), null, "bbb".getBytes());// 本行数据的第三列
            put.add("column3".getBytes(), null, "ccc".getBytes());// 本行数据的第三列
            Put put1 = new Put("han_r1".getBytes());
            put1.addColumn("cf".getBytes(),"a".getBytes(),"han_cf_a".getBytes());
    
            try {
                table.put(put);
                table.put(put1);
            } catch (IOException e) {
                e.printStackTrace();
            }
            System.out.println("end insert data ......");
        }
    
        /**
         * 删除一张表
         * @param tableName
         */
        public static void dropTable(String tableName) {
            try {
                HBaseAdmin admin = new HBaseAdmin(configuration);
                admin.disableTable(tableName);
                admin.deleteTable(tableName);
            } catch (MasterNotRunningException e) {
                e.printStackTrace();
            } catch (ZooKeeperConnectionException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
    
        }
        /**
         * 根据 rowkey删除一条记录
         * @param tablename
         * @param rowkey
         */
        public static void deleteRow(String tablename, String rowkey)  {
            try {
                HTable table = new HTable(configuration, tablename);
                List list = new ArrayList();
                Delete d1 = new Delete(rowkey.getBytes());
                list.add(d1);
    
                table.delete(list);
                System.out.println("删除行成功!");
    
            } catch (IOException e) {
                e.printStackTrace();
            }
    
    
        }
    
        /**
         * 组合条件删除
         * @param tablename
         * @param rowkey
         */
        public static void deleteByCondition(String tablename, String rowkey)  {
            //目前还没有发现有效的API能够实现 根据非rowkey的条件删除 这个功能能,还有清空表全部数据的API操作
    
        }
    
    
        /**
         * 查询所有数据
         * @param tableName
         */
        public static void QueryAll(String tableName) {
            HTablePool pool = new HTablePool(configuration, 1000);
            HTableInterface  table =  pool.getTable(tableName);
            try {
                ResultScanner rs = table.getScanner(new Scan());
                for (Result r : rs) {
                    System.out.println("获得到rowkey:" + new String(r.getRow()));
                    for (KeyValue keyValue : r.raw()) {
                        System.out.println("列:" + new String(keyValue.getFamily())
                                        +
                                        " :" + new String(keyValue.getQualifier())
                                        + "====值:" + new String(keyValue.getValue())
                                        + "===TIME===" + String.valueOf(keyValue.getTimestamp() )
    
                        );
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 单条件查询,根据rowkey查询唯一一条记录
         * @param tableName
         */
        public static void QueryByCondition1(String tableName) {
            System.out.println(" QueryByCondition1");
            HTablePool pool = new HTablePool(configuration, 1000);
            HTableInterface  table =   pool.getTable(tableName);
            try {
                Get scan = new Get("abcdef".getBytes());// 根据rowkey查询
                Result r = table.get(scan);
                System.out.println("获得到rowkey:" + new String(r.getRow()));
                for (KeyValue keyValue : r.raw()) {
                    System.out.println("列:" + new String(keyValue.getFamily())
                                    +
                                    " :" + new String(keyValue.getQualifier())
                                    + "====值:" + new String(keyValue.getValue())
                                    + "===TIME===" + String.valueOf(keyValue.getTimestamp() )
    
                    );
                }
    
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 单条件按查询,查询多条记录
         * @param tableName
         */
        public static void QueryByCondition2(String tableName) {
            System.out.println(" QueryByCondition2");
            try {
                HTablePool pool = new HTablePool(configuration, 1000);
                HTableInterface  table =   pool.getTable(tableName);
                FilterList filterList=new FilterList();
                SingleColumnValueFilter filter = new SingleColumnValueFilter(Bytes
                        .toBytes("column1"), null, CompareOp.EQUAL, Bytes
                        .toBytes("aaa") ); // 当列column1的值为aaa时进行查询
                 filter.setFilterIfMissing(true);
                filterList.addFilter(filter);
                Scan s = new Scan();
                s.setFilter(filterList);
                ResultScanner rs = table.getScanner(s);
                for (Result r : rs) {
                    System.out.println("获得到rowkey:" + new String(r.getRow()));
                    for (KeyValue keyValue : r.raw()) {
                        System.out.println("列:" + new String(keyValue.getFamily())
                                +
                                " :" + new String(keyValue.getQualifier())
                                + "====值:" + new String(keyValue.getValue())
                                + "===TIME===" + String.valueOf(keyValue.getTimestamp())
    
                         );
                    }
                }
                rs.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
    
        }
    
        /**
         * 组合条件查询
         * @param tableName
         */
        public static void QueryByCondition3(String tableName) {
            System.out.println(" QueryByCondition3");
            try {
                HTablePool pool = new HTablePool(configuration, 1000);
                HTableInterface  table =   pool.getTable(tableName);
    
                List<Filter> filters = new ArrayList<Filter>();
    
                Filter filter1 = new SingleColumnValueFilter(Bytes
                        .toBytes("column1"), null, CompareOp.EQUAL, Bytes
                        .toBytes("aaa"));
                filters.add(filter1);
    
                Filter filter2 = new SingleColumnValueFilter(Bytes
                        .toBytes("column2"), null, CompareOp.EQUAL, Bytes
                        .toBytes("bbb"));
                filters.add(filter2);
    
                Filter filter3 = new SingleColumnValueFilter(Bytes
                        .toBytes("column3"), null, CompareOp.EQUAL, Bytes
                        .toBytes("ccc"));
                filters.add(filter3);
    
                FilterList filterList1 = new FilterList(filters);
    
                Scan scan = new Scan();
                scan.setFilter(filterList1);
                ResultScanner rs = table.getScanner(scan);
                for (Result r : rs) {
                    System.out.println("获得到rowkey:" + new String(r.getRow()));
                    for (KeyValue keyValue : r.raw()) {
                        System.out.println("列:" + new String(keyValue.getFamily())
                                        +
                                        " :" + new String(keyValue.getQualifier())
                                        + "====值:" + new String(keyValue.getValue())
                                        + "===TIME===" + String.valueOf(keyValue.getTimestamp())
    
                        );
                    }
                }
                rs.close();
    
            } catch (Exception e) {
                e.printStackTrace();
            }
    
        }
    
    }
    View Code
    根据 SingleColumnValueFilter 按照列和值查询,会把没有该列的行查询出来,加入
    filter.setFilterIfMissing(true);
    就可以了
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  • 原文地址:https://www.cnblogs.com/cndavy/p/5189867.html
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