6.HBaseAPI操作
@Test
public void testCreateTable() throws Exception {
//1. 去读取加载classpath下的hbase-site.xml配置文件
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "192.168.0.208:2181,192.168.0.209:2181,192.168.0.210:2181");
//2. 拿到一个hbase的ddl客户端----建表、删表、禁用表、启用表。。。。。。。
HBaseAdmin hBaseAdmin = new HBaseAdmin(conf);
//3.创建表
TableName tableName = TableName.valueOf("user_info");
HTableDescriptor tableDesc = new HTableDescriptor(tableName);
//4.创建列
HColumnDescriptor family = new HColumnDescriptor("base_info");
family.setMaxVersions(3);//设置列族最多存几个版本
tableDesc.addFamily(family);
hBaseAdmin.createTable(tableDesc);
hBaseAdmin.close();
}
/**
* 插入数据
*
* @throws IOException
*/
@Test
public void testPut() throws IOException {
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "hdp-node01:2181,hdp-node02:2181,hdp-node03:2181");
//1. 拿一个hbase的DML客户端，针对一个指定的表
HTable userInfo = new HTable(conf, "user_info");
//2. 将要插入的kv数据封装到一个put对象中
Put put = new Put(Bytes.toBytes("rk-0001"));//行健
put.add(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("刘亦菲"));// 列族 字段 字段参数
put.add(Bytes.toBytes("base_info"), Bytes.toBytes("boyfriend"), Bytes.toBytes("任我行"));
Put put2 = new Put(Bytes.toBytes("rk-0002"));
put2.add(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("汤唯"));
put2.add(Bytes.toBytes("base_info"), Bytes.toBytes("boyfriend"), Bytes.toBytes("任我行"));
Put put3 = new Put(Bytes.toBytes("rk-0003"));
put3.add(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("杨颖"));
put3.add(Bytes.toBytes("base_info"), Bytes.toBytes("boyfriend"), Bytes.toBytes("任我行"));
ArrayList<Put> puts = new ArrayList<Put>();
puts.add(put);
puts.add(put2);
puts.add(put3);
userInfo.put(puts);
userInfo.close();
}
/**
* 删除表中的数据
*
* @throws Exception
*/
@Test
public void testDelete() throws Exception {
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "192.168.0.208:2181,192.168.0.209:2181,192.168.0.210:2181");
// 拿一个hbase的DML客户端，针对一个指定的表
HTable userInfo = new HTable(conf, "user_info");
// 如果delete中不指定要删除的列，则会删除整行
Delete delete = new Delete(Bytes.toBytes("rk-0003"));
delete.deleteColumn(Bytes.toBytes("base_info"), Bytes.toBytes("boyfriend"));
userInfo.delete(delete);
userInfo.close();
}
@Test
public void testUpdate() throws Exception {
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "192.168.0.208:2181,192.168.0.209:2181,192.168.0.210:2181");
// 拿一个hbase的DML客户端，针对一个指定的表
HTable userInfo = new HTable(conf, "user_info");
Put put = new Put(Bytes.toBytes("rk-0003"));
put.add(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("我的最爱"));
userInfo.put(put);
userInfo.close();
}
/**
* 查询一行中的数据
*
* @throws Exception
*/
@Test
public void testGet() throws Exception {
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "192.168.0.208:2181,192.168.0.209:2181,192.168.0.210:2181");
// 拿一个hbase的DML客户端，针对一个指定的表
HTable userInfo = new HTable(conf, "user_info");
// 根据行键构造一个get参数对象，如果get对象中不指定具体的列，则会返回整行
Get get = new Get(Bytes.toBytes("rk-0002"));
// 指定返回base_info中的所有列（kv）
get.addFamily(Bytes.toBytes("base_info"));
Result result = userInfo.get(get);
// 从结果集中取一个指定的列
// byte[] boyfriendBytes = result.getValue("base_info".getBytes(),
// "boyfriend".getBytes());
//
// String boyfriend = new String(boyfriendBytes);
// System.out.println(boyfriend);
/**
* 遍历result中所有的列
*/
List<KeyValue> kvs = result.list();
for (KeyValue kv : kvs) {
System.out.println(Bytes.toString(kv.getFamily())); // 列族
System.out.println(Bytes.toString(kv.getQualifier())); // 列
System.out.println(Bytes.toString(kv.getValue())); // 值
}
userInfo.close();
}
/**
* 范围查询，可以查询指定行键范围内的所有数据
*
* @throws IOException
*/
@Test
public void testScan() throws IOException {
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "192.168.0.208:2181,192.168.0.209:2181,192.168.0.210:2181");
// 拿一个hbase的DML客户端，针对一个指定的表
HTable userInfo = new HTable(conf, "user_info");
//行键范围中，含头不含尾
Scan scan = new Scan(Bytes.toBytes("rk-0001"), Bytes.toBytes("rk-0003"+"\0x00"));
ResultScanner scanner = userInfo.getScanner(scan);
//用迭代的方式来遍历scanner
/* Iterator<Result> iterator = scanner.iterator();
while(iterator.hasNext()){
Result result = iterator.next();
}*/
//用增强for循环遍历scanner
for (Result result : scanner) {
List<KeyValue> kvs = result.list();
for (KeyValue kv : kvs) {
System.out.println(Bytes.toString(kv.getFamily())); // 列族
System.out.println(Bytes.toString(kv.getQualifier())); // 列
System.out.println(Bytes.toString(kv.getValue())); // 值
}
}
userInfo.close();
}
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