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KuDu 常用Api(java)

1.首先创建一个maven工程，添加一下依赖

<dependency>
      <groupId>org.apache.kudu</groupId>
      <artifactId>kudu-client</artifactId>
      <version>1.4.0</version>
 </dependency>

2.创建表

package cn.wcb.kudu;

import org.apache.kudu.ColumnSchema;
import org.apache.kudu.Schema;
import org.apache.kudu.Type;
import org.apache.kudu.client.CreateTableOptions;
import org.apache.kudu.client.KuduClient;
import org.apache.kudu.client.KuduException;

import java.util.LinkedList;

public class CreateTable {

    private static ColumnSchema newColumn(String name, Type type, Boolean isKey){
        ColumnSchema.ColumnSchemaBuilder column =
                new ColumnSchema.ColumnSchemaBuilder(name, type);
        column.key(isKey);
        return column.build();
    }

    public static void main(String[] args) {
        //master地址
        String masterAddr = "192.168.56.56";

        //创建kudu的数据库连接
        KuduClient client = new KuduClient.KuduClientBuilder(masterAddr)
                .defaultSocketReadTimeoutMs(6000).build();

        //设置表的schema
        LinkedList<ColumnSchema> columns = new LinkedList<>();

        /*
         *和RDBMS不同的是，Kudu不提供自动递增列功能，因此应用程序必须始终
         * 在插入期间提供完整的主键
         */
        columns.add(newColumn("id",Type.INT32,true));
        columns.add(newColumn("name",Type.STRING,false));
        Schema schema = new Schema(columns);

        //创建表时提供的所有选项
        CreateTableOptions options = new CreateTableOptions();

        //设置表的replica备份和分区规则
        LinkedList<String> parcols = new LinkedList<>();
        parcols.add("id");

        //设置表的备份数
        options.setNumReplicas(1);

        //设置hash分区和数量
        options.addHashPartitions(parcols,3);

        try {
            client.createTable("student",schema,options);
        } catch (KuduException e) {
            e.printStackTrace();
        } finally {
            try {
                client.close();
            } catch (KuduException e) {
                e.printStackTrace();
            }
        }
    }
}

3.删除表

package cn.wcb.kudu;

import org.apache.kudu.client.KuduClient;
import org.apache.kudu.client.KuduException;

public class DropTable {

    public static void main(String[] args) {
        //master地址
        String masterAddr = "192.168.56.56";

        KuduClient client = new KuduClient.KuduClientBuilder(masterAddr)
                .defaultSocketReadTimeoutMs(6000).build();

        try {
            client.deleteTable("student");
        } catch (KuduException e) {
            e.printStackTrace();
        }finally {
            try {
                client.close();
            } catch (KuduException e) {
                e.printStackTrace();
            }
        }

    }
}

4.插入数据

package cn.wcb.kudu;

import org.apache.kudu.client.*;

public class InsertRow {

    public static void main(String[] args) {
        //master地址
        String masterAddr = "192.168.56.56";

        KuduClient client = new KuduClient.KuduClientBuilder(masterAddr)
                .defaultSocketReadTimeoutMs(6000).build();

        try {
            KuduTable table = client.openTable("student");
            KuduSession kuduSession = client.newSession();

            kuduSession.setFlushMode(SessionConfiguration.FlushMode.MANUAL_FLUSH);
            kuduSession.setMutationBufferSpace(3000);
            for (int i = 0; i <10 ; i++) {
                Insert insert = table.newInsert();
                insert.getRow().addInt("id",i);
                insert.getRow().addString("name",i+"号");
                kuduSession.flush();
                kuduSession.apply(insert);
            }
            kuduSession.close();
        } catch (KuduException e) {
            e.printStackTrace();
        } finally {
            try {
                client.close();
            } catch (KuduException e) {
                e.printStackTrace();
            }
        }

    }
}

5.查询数据

package cn.wcb.kudu;

import org.apache.kudu.client.*;

public class FindRow {

    public static void main(String[] args) {
        //master地址
        String masterAddr = "192.168.56.56";

        KuduClient client = new KuduClient.KuduClientBuilder(masterAddr)
                .defaultSocketReadTimeoutMs(6000).build();

        try {
            KuduTable table = client.openTable("student");

            //创建scanner扫描
            KuduScanner scanner = client.newScannerBuilder(table).build();

            //遍历数据
            while(scanner.hasMoreRows()){
                for (RowResult rowResult : scanner.nextRows()){
                    System.out.println(rowResult.getInt("id")
                    +"\t"+rowResult.getString("name"));
                }
            }
        } catch (KuduException e) {
            e.printStackTrace();
        } finally {
            try {
                client.close();
            } catch (KuduException e) {
                e.printStackTrace();
            }
        }

    }
}

6.更改表数据

package cn.wcb.kudu;

import org.apache.kudu.client.*;

public class UpdateRow {

    public static void main(String[] args) {
        //master地址
        String masterAddr = "192.168.56.56";

        KuduClient client = new KuduClient.KuduClientBuilder(masterAddr)
                .defaultSocketReadTimeoutMs(6000).build();

        try {
            KuduTable table = client.openTable("student");
            KuduSession session = client.newSession();

            session.setFlushMode(SessionConfiguration.FlushMode.AUTO_FLUSH_SYNC);

            //更新数据
            Update update = table.newUpdate();
            PartialRow row = update.getRow();
            row.addInt("id",1);
            row.addString("name","didi");
            session.apply(update);

            session.close();
        } catch (KuduException e) {
            e.printStackTrace();
        } finally {
            try {
                client.close();
            } catch (KuduException e) {
                e.printStackTrace();
            }
        }

    }
}

7.删除指定行

package cn.wcb.kudu;

import org.apache.kudu.client.*;

public class DeleteRow {

    public static void main(String[] args) {
        //master地址
        String masterAddr = "192.168.56.56";

        KuduClient client = new KuduClient.KuduClientBuilder(masterAddr)
                .defaultSocketReadTimeoutMs(6000).build();

        try {
            KuduTable table = client.openTable("student");
            KuduSession session = client.newSession();

            //删除数据
            Delete delete = table.newDelete();
            //注意：行删除和更新操作必须指定要更改行的行的完整主键
            delete.getRow().addInt("id",1);
            session.flush();
            session.apply(delete);

            session.close();
        } catch (KuduException e) {
            e.printStackTrace();
        } finally {
            try {
                client.close();
            } catch (KuduException e) {
                e.printStackTrace();
            }
        }

    }
}