我的環境:完全分佈式集羣,不是hbase自帶的zookeeper,是獨立的zookeeper
該代碼操作過程:在hbase中創建表、插入數據、查詢數據
注意:如果缺少相應的包,請上網下載後,導入項目即可
代碼如下:
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import java.io.IOException;
public class ExampleForHbase {
public static Configuration configuration; // 管理Hbase的配置信息
public static Connection connection; // 管理Hbase連接
public static Admin admin; // 管理Hbase數據庫的信息
public static void main(String[] args) throws IOException {
init(); //連接
String colF[] ={"score"};
createTable("student",colF); // 建表
insertData("student","zhangsan","score","English","69");
insertData("student","zhangsan","score","Math","86");
insertData("student","zhangsan","score","Computer","77");
getData("student","zhangsan","score","Computer");
}
// 操作數據庫之前,建立連接
public static void init(){
configuration = HBaseConfiguration.create();
configuration.set("hbase.rootdir","hdfs://master:9000/hbase");
configuration.set("hbase.zookeeper.quorum","master,slave1,slave2"); // 設置zookeeper節點
configuration.set("hbase.zookeeper.property.clientPort","2181"); // 設置zookeeper節點
try{
connection = ConnectionFactory.createConnection(configuration);
admin = connection.getAdmin();
}catch (IOException e){
e.printStackTrace();
}
}
// 創建表
/*
* @param myTableName 表名
* @param colFamily 列族數組
* @throws Exception
* */
public static void createTable(String myTableName,String[] colFamily) throws IOException{
TableName tableName = TableName.valueOf(myTableName);
if(admin.tableExists(tableName)){
System.out.println("Table exists");
}else {
HTableDescriptor hTableDescriptor = new HTableDescriptor(tableName);
for(String str:colFamily){
HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(str);
hTableDescriptor.addFamily(hColumnDescriptor);
}
admin.createTable(hTableDescriptor);
}
}
// 添加單元格數據
/*
* @param tableName 表名
* @param rowKey 行鍵
* @param colFamily 列族
* @param col 列限定符
* @param val 數據
* @thorws Exception
* */
public static void insertData(String tableName,String rowKey,String colFamily,String col,String val) throws IOException{
Table table = connection.getTable(TableName.valueOf(tableName));
Put put = new Put(rowKey.getBytes());
put.addColumn(colFamily.getBytes(),col.getBytes(),val.getBytes());
table.put(put);
table.close();
}
//瀏覽數據
/*
* @param tableName 表名
* @param rowKey 行
* @param colFamily 列族
* @param col 列限定符
* @throw IOException
* */
public static void getData(String tableName,String rowKey,String colFamily,String col) throws IOException{
Table table = connection.getTable(TableName.valueOf(tableName));
Get get = new Get(rowKey.getBytes());
get.addColumn(colFamily.getBytes(),col.getBytes());
Result result =table.get(get);
System.out.println(new String(result.getValue(colFamily.getBytes(),col==null?null:col.getBytes())));
table.close();
}
// 操作數據庫之後,關閉連接
public static void close(){
try{
if(admin!=null){
admin.close(); // 退出用戶
}
if(null != connection){
connection.close(); // 關閉連接
}
}catch (IOException e){
e.printStackTrace();
}
}
}
補充;使用maven時,pom如下:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>hbaseAction</groupId>
<artifactId>hbaseAction</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-common</artifactId>
<version>LATEST</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-http</artifactId>
<version>LATEST</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-client</artifactId>
<version>LATEST</version>
</dependency>
</dependencies>
</project>