最近写HBase,发现很多功能都不建议使用,依据官方的文档写了份关于增删改查的测试案例,供学习交流。
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.io.compress.Compression;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.Before;
import org.junit.Test;
import java.io.IOException;
/**
* Hbase 基本CRUD 样例代码 覆盖Put Get Delete checkAndPut checkAndDelete Scan
* 通过上面的各种操作的例子, 会基本覆盖Htable可以用的的所有方法
* 这里不涉及Hbase 管理代码的操作
* @author seagle
*
*/
public class HbaseCRUDTest {
@Before
public void beforeTest(){
}
@Test
public void createTest() throws IOException {
Configuration conf = HBaseConfiguration.create();
Connection connection = ConnectionFactory.createConnection(conf);
String tablename = "test";
String familyname="info";
Admin admin = connection.getAdmin();
HTableDescriptor table = new HTableDescriptor(TableName.valueOf(tablename));
table.addFamily(new HColumnDescriptor(familyname).setCompressionType(Compression.Algorithm.SNAPPY));
System.out.print("Creating table. ");
// 判断是否存在,如果存在,先删除.
if (admin.tableExists(table.getTableName())) {
admin.disableTable(table.getTableName());
admin.deleteTable(table.getTableName()); // 删除存在的表
}
// 创建表
admin.createTable(table);
System.out.println(" Done.");
}
@Test
public void putTest() throws IOException {
Configuration conf = HBaseConfiguration.create();
// Use below code for HBase version 1.x.x or above.
Connection connection = ConnectionFactory.createConnection(conf);
TableName tableName = TableName.valueOf(“test”);
Table table = connection.getTable(tableName);
Put put = new Put(Bytes.toBytes("8")); // row key
// put.addColumn(Bytes.toBytes(“family”),Bytes.toBytes(“qualifier”),Bytes.toBytes(“value”));
put.addColumn(Bytes.toBytes("info"),Bytes.toBytes("level_1"),Bytes.toBytes("4"));
put.addColumn(Bytes.toBytes("info"),Bytes.toBytes("level_2"),Bytes.toBytes("4"));
put.addColumn(Bytes.toBytes("info"),Bytes.toBytes("level_3"),Bytes.toBytes("4"));
put.addColumn(Bytes.toBytes("info"),Bytes.toBytes("level_4"),Bytes.toBytes("4"));
table.put(put);
}
@Test
public void getTest() throws IOException {
Configuration conf = HBaseConfiguration.create();
// Use below code for HBase version 1.x.x or above.
Connection connection = ConnectionFactory.createConnection(conf);
TableName tableName = TableName.valueOf(“test”);
Table table = connection.getTable(tableName);
StringBuffer sb = null;
Get get = new Get(Bytes.toBytes("8"));
Result result = table.get(get);
for (Cell c : result.rawCells()) {
sb = new StringBuffer(Bytes.toString(CellUtil.cloneRow(c)));
sb.append("==> ");
sb.append(Bytes.toString(CellUtil.cloneFamily(c)));
sb.append("{");
sb.append(Bytes.toString(CellUtil.cloneQualifier(c)));
sb.append(":");
sb.append(Bytes.toString(CellUtil.cloneValue(c)));
sb.append("}");
System.out.println(sb);
}
}
@Test
public void scanTest() throws IOException {
Configuration conf = HBaseConfiguration.create();
Connection connection = ConnectionFactory.createConnection(conf);
TableName tableName = TableName.valueOf("test");
Table table = connection.getTable(tableName);
StringBuffer sb = null;
Scan scan = new Scan();
ResultScanner scanner = table.getScanner(scan);
for (Result res : scanner) {
for (Cell c : res.rawCells()) {
sb = new StringBuffer(Bytes.toString(CellUtil.cloneRow(c)));
sb.append(" ==> ");
sb.append(Bytes.toString(CellUtil.cloneFamily(c)));
sb.append(" {");
sb.append(Bytes.toString(CellUtil.cloneQualifier(c)));
sb.append(":");
sb.append(Bytes.toString(CellUtil.cloneValue(c)));
sb.append("}");
System.out.println(sb.toString());
}
}
}
@Test
public void modifyTest() throws IOException{
Configuration conf = HBaseConfiguration.create();
try (Connection connection = ConnectionFactory.createConnection(conf);
Admin admin = connection.getAdmin()) {
TableName tableName = TableName.valueOf("test");
if (!admin.tableExists(tableName)) {
System.out.println("表不存在");
System.exit(-1);
}
HTableDescriptor table = new HTableDescriptor(tableName);
// add family
// HColumnDescriptor newColumn = new HColumnDescriptor(“testinfo”);
// newColumn.setCompactionCompressionType(Compression.Algorithm.GZ);
// newColumn.setMaxVersions(HConstants.ALL_VERSIONS);
// admin.addColumn(tableName, newColumn);
// Update existing column family
HColumnDescriptor existingColumn = new HColumnDescriptor("info");
existingColumn.setCompactionCompressionType(Compression.Algorithm.GZ);
existingColumn.setMaxVersions(HConstants.ALL_VERSIONS);
table.modifyFamily(existingColumn);
admin.modifyTable(tableName, table);
// Disable an existing table
// admin.disableTable(tableName);
// Delete an existing column family
// admin.deleteColumn(tableName, “testinfo”.getBytes(“UTF-8”));
// Delete a table (Need to be disabled first)
// admin.deleteTable(tableName);
}
}
@Test
public void deleteColumnDataTest() throws IOException {
Configuration conf = HBaseConfiguration.create();
Connection connection = ConnectionFactory.createConnection(conf);
TableName tableName = TableName.valueOf("test");
Table table = connection.getTable(tableName);
Delete delete = new Delete(Bytes.toBytes("8"));
table.delete(delete);
System.out.println("删除数据成功");
}
}
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