云星数据---Apache Flink实战系列(精品版)】：Flink流处理API详解与编程实战009-DataStream与MySql自定义sink和source(Java版)001

一、在MySQL中准备测试数据

1.执行命令

1.查询数据库SHOW DATABASES;2.创建数据库CREATE DATABASE flinktest;3.使用数据库USE flinktest;4.创建表格CREATE TABLE Student(    stuid INT(11) PRIMARY KEY NOT NULL AUTO_INCREMENT,    stuname VARCHAR(10) NOT NULL,    stuaddr VARCHAR(40) NOT NULL,    stusex VARCHAR(10) NOT NULL);5.插入数据INSERT INTO Student(stuid,stuname,stuaddr,stusex)VALUES(1,"xiaoming","henan zhengzhou", "male")INSERT INTO Student(stuid,stuname,stuaddr,stusex)VALUES(2,"xiaoqiang","shandong jinan", "female")INSERT INTO Student(stuid,stuname,stuaddr,stusex)VALUES(3,"xiaohua","hebei shijiazhuang",   "male")INSERT INTO Student(stuid,stuname,stuaddr,stusex)VALUES(4,"xiaohong","yunnan kunming",  "female")6.查询数据SELECT * FROM Student ;

2.执行效果

二、测试JDBC连接

1.在pom.xml中添加驱动依赖

<dependency>    <groupId>mysql</groupId>    <artifactId>mysql-connector-java</artifactId>    <version>5.1.35</version></dependency>

2.定义Student实体类，用于封装数据

package code.book.stream.customsinkandsource.jdbc.java;/** * 用于存储数据库中的数据，作为bean使用 */public class Student {    int stuid;    String stuname;    String stuaddr;    String stusex;    public Student(int stuid, String stuname, String stuaddr, String stusex) {        this.stuid = stuid;        this.stuname = stuname;        this.stuaddr = stuaddr;        this.stusex = stusex;    }    public int getStuid() {        return stuid;    }    public void setStuid(int stuid) {        this.stuid = stuid;    }    public String getStuname() {        return stuname;    }    public void setStuname(String stuname) {        this.stuname = stuname;    }    public String getStuaddr() {        return stuaddr;    }    public void setStuaddr(String stuaddr) {        this.stuaddr = stuaddr;    }    public String getStusex() {        return stusex;    }    public void setStusex(String stusex) {        this.stusex = stusex;    }    @Override    public String toString() {        return "Student{" +                "stuid=" + stuid +                ", stuname='" + stuname + '\'' +                ", stuaddr='" + stuaddr + '\'' +                ", stusex='" + stusex + '\'' +                '}';    }}

2.执行JDBC测试程序

package code.book.stream.customsinkandsource.jdbc.java;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.Statement;/** * 本类主要用于检测jdbc连接是否成功 */public class JdbcTest {    public static void main(String[] args) throws Exception {        String driver = "com.mysql.jdbc.Driver";        String url = "jdbc:mysql://qingcheng11:3306/flinktest";        String username = "root";        String password = "qingcheng";        Connection connection = null;        Statement statement = null;        try {            //1.加载驱动            Class.forName(driver);            //2.创建连接            connection = DriverManager.getConnection(url, username, password);            //3.获得执行语句            statement = connection.createStatement();            //4.执行查询，获得结果集            ResultSet resultSet = statement.executeQuery(            "select stuid,stuname,stuaddr,stusex from Student");            //5.处理结果集            while (resultSet.next()) {                Student student = new Student(                resultSet.getInt("stuid"),                resultSet.getString("stuname").trim(),                resultSet.getString("stuaddr").trim(),                resultSet.getString("stusex").trim());                System.out.println(student);            }        } catch (Exception e) {            e.printStackTrace();        } finally {            //6.关闭连接，释放资源            if (connection != null) {                connection.close();            }            if (statement != null) {                statement.close();            }        }    }}

2.JDBC测试程序成功输出

Student{stuid=1, stuname='xiaoming', stuaddr='henan zhengzhou', stusex='male'}Student{stuid=2, stuname='xiaoqiang', stuaddr='shandong jinan', stusex='female'}Student{stuid=3, stuname='xiaohua', stuaddr='hebei shijiazhuang', stusex='male'}Student{stuid=4, stuname='xiaohong', stuaddr='yunnan kunming', stusex='female'}