KUDU的java操作

参考：kudu原理与使用

5、KUDU的java操作

5.1、导入依赖

<dependency>
    <groupId>org.apache.kudu</groupId>
    <artifactId>kudu-client</artifactId>
    <version>${kudu.version}</version>
    <scope>test</scope>
</dependency>

<!--导入kudu的客户端工具-->
<dependency>
    <groupId>org.apache.kudu</groupId>
    <artifactId>kudu-client-tools</artifactId>
    <version>${kudu.version}</version>
</dependency>

5.2、API

5.2.1、表创建

/**
 * 创建表
 * @throws Exception
 */
public static void createTable() throws Exception{
	//1、创建一个client
	KuduClient client = new KuduClientBuilder(KUDU_MASTER).build();
	//2、创建schema信息
	List<ColumnSchema> columns = new ArrayList<ColumnSchema>();
	columns.add(new ColumnSchema.ColumnSchemaBuilder("id", Type.INT32).key(true).nullable(false).build());
	columns.add(new ColumnSchema.ColumnSchemaBuilder("name", Type.STRING).key(false).nullable(false).build());
	columns.add(new ColumnSchema.ColumnSchemaBuilder("age", Type.INT32).key(false).nullable(false).build());
	Schema schema = new Schema(columns);
	//3、指定分区字段
	List<String> partions = new ArrayList<String>();
	partions.add("id");
	//4、指定分区方式为hash分区、6个分区，一个副本
	CreateTableOptions options = new CreateTableOptions().addHashPartitions(partions, 6).setNumReplicas(1);
	//5、创建表，
	client.createTable("person",schema,options);

	client.close();
}

5.2.2、Insert

/**
 * 插入数据
 * @throws Exception
 */
public static void add() throws Exception{
	//1、创建一个client
	KuduClient client = new KuduClientBuilder(KUDU_MASTER).build();
	//2、打开表
	KuduTable table = client.openTable("person");
	//3、创建一个session会话
	KuduSession session = client.newSession();
	//4、创建插入
	Insert insert = table.newInsert();
	//5、指定插入数据
	insert.getRow().addInt("id",1);
	insert.getRow().addInt("age",18);
	insert.getRow().addString("name","张三");
	//6、应用插入
	session.apply(insert);

	session.close();

	client.close();

}

5.2.3、update

/**
 * 更新数据
 * @throws Exception
 */
public static void update() throws Exception{
	//1、创建kudu client
	KuduClient client = new KuduClientBuilder(KUDU_MASTER).build();
	//2、打开表
	KuduTable table = client.openTable("person");

	KuduSession session = client.newSession();

	Update update = table.newUpdate();
	update.getRow().addInt("id",1);
	update.getRow().addString("name","李四");

	session.apply(update);
	session.flush();
	session.close();

	client.close();
}

5.2.4、delete

 

/**
 * 删除数据
 * @throws Exception
 */
public static void delete() throws Exception{
	//1、创建kudu client
	KuduClient client = new KuduClientBuilder(KUDU_MASTER).build();
	//2、打开表
	KuduTable table = client.openTable("person");

	KuduSession session = client.newSession();

	Delete delete = table.newDelete();
	delete.getRow().addInt("id",1);


	session.apply(delete);
	session.flush();
	session.close();

	client.close();
}

5.2.5、query

/**
 * 条件查询 select * from person where id=1
 * @throws Exception
 */
public static void query() throws Exception{
	//1、创建kudu client
	KuduClient client = new KuduClientBuilder(KUDU_MASTER).build();
	//2、打开表
	KuduTable table = client.openTable("person");
	//3、创建scanner扫描器
	KuduScanner.KuduScannerBuilder kuduScannerBuilder = client.newScannerBuilder(table);
	//4、创建查询条件
	KuduPredicate filter = KuduPredicate.newComparisonPredicate(table.getSchema().getColumn("id"), KuduPredicate.ComparisonOp.EQUAL, 1);
	//5、将查询条件加入到scanner中
	KuduScanner scanner = kuduScannerBuilder.addPredicate(filter).build();
	//6、获取查询结果
	while (scanner.hasMoreRows()){
		RowResultIterator rows = scanner.nextRows();
		while (rows.hasNext()){
			RowResult row = rows.next();
			Integer id = row.getInt("id");
			String name = row.getString("name");
			int age = row.getInt("age");
			System.out.println(id+"---"+name+"---"+age);
		}
	}
	//7、关闭client
	client.close();
}

 

来源：oschina

链接：https://my.oschina.net/u/4265623/blog/4258536