一、添加Maven座標
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.48</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-jdbc_2.12</artifactId>
<version>1.8.0</version>
</dependency>
二、建表
CREATE TABLE `temp` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
`time` varchar(255) DEFAULT NULL,
`type` bigint(20) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
三、 Show Code
package com.fwmagic.flink.batch;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.common.typeinfo.BasicTypeInfo;
import org.apache.flink.api.java.DataSet;
import org.apache.flink.api.java.ExecutionEnvironment;
import org.apache.flink.api.java.io.jdbc.JDBCInputFormat;
import org.apache.flink.api.java.io.jdbc.JDBCOutputFormat;
import org.apache.flink.api.java.operators.DataSource;
import org.apache.flink.api.java.tuple.Tuple3;
import org.apache.flink.api.java.typeutils.RowTypeInfo;
import org.apache.flink.types.Row;
import java.util.concurrent.TimeUnit;
public class BatchDemoOperatorMysql {
public static void main(String[] args) throws Exception {
String driverClass = "com.mysql.jdbc.Driver";
String dbUrl = "jdbc:mysql://localhost:3306/test";
String userNmae = "root";
String passWord = "123456";
String sql = "insert into test.temp (name,time,type) values (?,?,?)";
ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
/**
* 文件內容:
* 關羽,2019-10-14 00:00:01,1
* 張飛,2019-10-14 00:00:02,2
* 趙雲,2019-10-14 00:00:03,3
*/
String filePath = "/Users/temp/data.csv";
//讀csv文件內容,轉成Row對象
DataSet<Row> outputData = env.readCsvFile(filePath).fieldDelimiter(",").types(String.class, String.class, Long.class).map(new MapFunction<Tuple3<String, String, Long>, Row>() {
@Override
public Row map(Tuple3<String, String, Long> t) throws Exception {
Row row = new Row(3);
row.setField(0, t.f0.getBytes("UTF-8"));
row.setField(1, t.f1.getBytes("UTF-8"));
row.setField(2, t.f2.longValue());
return row;
}
});
//將Row對象寫到mysql
outputData.output(JDBCOutputFormat.buildJDBCOutputFormat()
.setDrivername(driverClass)
.setDBUrl(dbUrl)
.setUsername(userNmae)
.setPassword(passWord)
.setQuery(sql)
.finish());
//觸發執行
env.execute("insert data to mysql");
System.out.println("mysql寫入成功!");
TimeUnit.SECONDS.sleep(6);
//讀mysql
DataSource<Row> dataSource = env.createInput(JDBCInputFormat.buildJDBCInputFormat()
.setDrivername(driverClass)
.setDBUrl(dbUrl)
.setUsername(userNmae)
.setPassword(passWord)
.setQuery("select * from temp")
.setRowTypeInfo(new RowTypeInfo(BasicTypeInfo.STRING_TYPE_INFO, BasicTypeInfo.STRING_TYPE_INFO, BasicTypeInfo.LONG_TYPE_INFO))
.finish());
//獲取數據並打印
dataSource.map(new MapFunction<Row, String>() {
@Override
public String map(Row value) throws Exception {
System.out.println(value);
return value.toString();
}
}).print();
}
}
四、注意事項
- 數據寫入mysql的DataSet泛型要求是row,須要轉換;
- 數據讀取的結果也是row類型,不能直接print,須要轉換;
- 數據寫入後必定要加上env.execute(),觸發任務執行;
- 涉及到中文的,須要轉換成UTF-8,否則數據庫中會出現亂碼。