java api 中文手册_java查询hbase

 1 package com.shujia;  2 
 3 import org.apache.hadoop.conf.Configuration;  4 import org.apache.hadoop.hbase.HBaseConfiguration;  5 import org.apache.hadoop.hbase.HColumnDescriptor;  6 import org.apache.hadoop.hbase.HTableDescriptor;  7 import org.apache.hadoop.hbase.TableName;  8 import org.apache.hadoop.hbase.client.Admin;  9 import org.apache.hadoop.hbase.client.Connection; 10 import org.apache.hadoop.hbase.client.ConnectionFactory; 11 
12 import java.io.IOException; 13 
14 public class Demo01 { 15     public static void main(String[] args) throws IOException { 16 
17         //创建配置，指定zk集群
18         Configuration conf = HBaseConfiguration.create(); 19         conf.set("hbase.zookeeper.quorum","master,node1,node2"); 20 
21         //创建连接
22         Connection coon = ConnectionFactory.createConnection(conf); 23 
24         //创建admin对象
25         Admin admin = coon.getAdmin(); 26 
27         //创建表
28         HTableDescriptor test_api = new HTableDescriptor(TableName.valueOf("test_api")); 29 
30         //创建列簇
31         HColumnDescriptor cf1 = new HColumnDescriptor("cf1"); 32 
33         //配置列簇
34         cf1.setTimeToLive(20); //设置死亡时间20s
35         cf1.setMaxVersions(3); //设置版本 36 
37         //增加列簇
38  test_api.addFamily(cf1); 39 
40         //创建表
41  admin.createTable(test_api); 42 
43         //关闭连接
44  coon.close(); 45  } 46 }

 1 package com.shujia;  2 
 3 import org.apache.hadoop.conf.Configuration;  4 import org.apache.hadoop.hbase.HBaseConfiguration;  5 import org.apache.hadoop.hbase.HColumnDescriptor;  6 import org.apache.hadoop.hbase.HTableDescriptor;  7 import org.apache.hadoop.hbase.TableName;  8 import org.apache.hadoop.hbase.client.*;  9 import org.apache.hadoop.hbase.util.Addressing;  10 import org.apache.hadoop.hbase.util.Bytes;  11 import org.junit.After;  12 import org.junit.Before;  13 import org.junit.Test;  14 
 15 import javax.swing.tree.VariableHeightLayoutCache;  16 import java.io.BufferedReader;  17 import java.io.FileReader;  18 import java.io.IOException;  19 import java.util.ArrayList;  20 
 21 public class Demo03API {  22  Connection conn;  23     TableName table=TableName.valueOf("test_api");  24 
 25  @Before  26     public void init() throws IOException {  27         Configuration conf = HBaseConfiguration.create();  28         conf.set("hbase.zookeeper.quorum","master,node1,node2");  29 
 30         conn = ConnectionFactory.createConnection(conf);  31  }  32     //put
 33  @Test  34     public void Put() throws IOException {  35         Table test_api = conn.getTable(TableName.valueOf("test_api"));  36         Put put = new Put("001".getBytes());  37         put.addColumn("cf1".getBytes(),"name".getBytes(),"张三".getBytes());  38  test_api.put(put);  39  }  40 
 41     // putAll 读取students.txt 并将数据写入HBase
 42  @Test  43     public void PutAll() throws IOException {  44         // 创建students表 info
 45         Admin admin = conn.getAdmin();  46         TableName studentsT = TableName.valueOf("students");  47         // 判断表是否存在
 48         if (!admin.tableExists(studentsT)) {  49             HTableDescriptor students = new HTableDescriptor(studentsT);  50             HColumnDescriptor info = new HColumnDescriptor("info");  51  students.addFamily(info);  52  admin.createTable(students);  53  }  54 
 55         Table stu = conn.getTable(studentsT);  56 
 57 
 58         BufferedReader br = new BufferedReader(new FileReader("data/students.txt"));  59         String line = null;  60         ArrayList<Put> puts = new ArrayList<Put>();  61         int batchSize = 11;  62         while ((line = br.readLine()) != null) {  63 
 64             // 读取每一行数据
 65             String[] split = line.split(",");  66             String id = split[0];  67             String name = split[1];  68             String age = split[2];  69             String gender = split[3];  70             String clazz = split[4];  71             Put put = new Put(id.getBytes());  72             put.addColumn("info".getBytes(), "name".getBytes(), name.getBytes());  73             put.addColumn("info".getBytes(), "age".getBytes(), age.getBytes());  74             put.addColumn("info".getBytes(), "gender".getBytes(), gender.getBytes());  75             put.addColumn("info".getBytes(), "clazz".getBytes(), clazz.getBytes());  76             puts.add(put); // 将每条数据构建好的put对象加入puts列表
 77             if (puts.size() == batchSize) {  78                 stu.put(puts); // 批量写入
 79                 puts = new ArrayList<Put>();  80  }  81  }  82         if (puts.size() != 0) {  83             stu.put(puts); // 批量写入
 84  }  85 
 86  }  87     //get
 88  @Test  89     public void Get() throws IOException {  90         Table test_api = conn.getTable(table);  91         Get get = new Get("001".getBytes());  92         Result rs = test_api.get(get);  93         byte[] value = rs.getValue("cf1".getBytes(), "name".getBytes());  94  System.out.println( Bytes.toString(value));  95  }  96 
 97 
 98     @Test//alter table 修改表
 99     public void alterTable() throws IOException { 100         Admin admin = conn.getAdmin(); 101         //获取表原有的结果
102         HTableDescriptor tableDescriptor = admin.getTableDescriptor(table); 103         //获取所有列簇构成的数组
104         HColumnDescriptor[] columnFamilies = tableDescriptor.getColumnFamilies(); 105         //遍历列簇
106         for (HColumnDescriptor columnFamily : columnFamilies) { 107             //获取列簇名称
108             String cfName = columnFamily.getNameAsString(); 109             //对列簇名为cf1的进行修改
110             if("cf1".equals(cfName)){ 111                 //修改TTL
112                 columnFamily.setTimeToLive(100000); 113  } 114  } 115         //修改表结构
116  admin.modifyTable(table,tableDescriptor); 117 
118 
119  } 120 
121  @After 122     public void closed() throws IOException { 123  conn.close(); 124  } 125 }