import java.sql.*;
import java.util.LinkedList;
import java.util.List;
/**
* @Author: liyue
* @Date: 2022/03/30/15:09
* @Description:
*/
public class Mysql8Instance {
/**
* mysql连接地址
* 示例 jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&useSSL=false&characterEncoding=utf-8&serverTimezone=Asia/Shanghai&allowMultiQueries=true&allowPublicKeyRetrieval=true&zeroDateTimeBehavior=CONVERT_TO_NULL
*/
/**
* mysql驱动
*/
private String driver = "com.mysql.cj.jdbc.Driver";
/**
* 连接地址
*/
private String host;
/**
* mysql端口
*/
private Integer port;
/**
* 默认数据库
*/
private String database;
/**
* mysql账号名
*/
private String username;
/**
* mysql密码
*/
private String password;
private Connection conn;
public Mysql8Instance(String host, Integer port, String database, String username, String password) {
this.host = host;
this.port = port;
this.database = database;
this.username = username;
this.password = password;
try {
String url = "jdbc:mysql://" + host + ":" + port + "/" + database + "?useUnicode=true&useSSL=false&characterEncoding=utf-8&serverTimezone=Asia/Shanghai&allowMultiQueries=true&allowPublicKeyRetrieval=true&zeroDateTimeBehavior=CONVERT_TO_NULL";
conn = DriverManager.getConnection(url, username, password);
} catch (Exception e) {
System.err.println("连接池获取失败");
throw new RuntimeException(e);
}
}
public void execute(String sql) {
try (Statement statement = conn.createStatement();) {
Class.forName(driver);
statement.execute(sql);
System.out.println("执行sql成功,sql:" + sql);
} catch (Exception e) {
System.err.println("sql执行失败:" + sql);
throw new RuntimeException(e);
}
}
public List<List<Object>> query(String sql) {
List<List<Object>> lists = new LinkedList<>();
long startTime = System.currentTimeMillis();
try (PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs = ps.executeQuery()) {
List<Object> titles = new LinkedList<>();
ResultSetMetaData rsmd = rs.getMetaData();
final int columnCount = rsmd.getColumnCount();
// 结果为空时直接返回,方便后续处理。关于如何判空参见下面链接
boolean rsIsEmpty = !rs.isBeforeFirst();
if (rsIsEmpty) {
return lists;
}
// 添加列名方便后续处理
for (int i = 1; i <= columnCount; i++) {
titles.add(rsmd.getColumnName(i));
}
lists.add(titles);
while (rs.next()) {
List<Object> list = new LinkedList<>();
for (int i = 1; i <= columnCount; i++) {
list.add((rs.getString(i) == null || rs.getString(i).equals("")) ? "" : rs.getString(i).trim());
}
lists.add(list);
}
} catch (SQLException e) {
System.err.println("查询sql失败,sql:" + sql);
throw new RuntimeException(e);
}
long endTime = System.currentTimeMillis();
System.out.println("查询sql:" + sql + ", 运行时长:" + (endTime - startTime) + " ms, 数据量: " + lists.size());
return lists;
}
@Override
protected void finalize() throws Throwable {
close();
super.finalize();
}
public void close() {
try {
conn.close();
System.out.println("连接关闭成功");
} catch (Exception e) {
System.err.println("连接关闭失败");
throw new RuntimeException(e);
}
}
public Mysql8Instance() {
}
public String getDriver() {
return driver;
}
public void setDriver(String driver) {
this.driver = driver;
}
public String getHost() {
return host;
}
public void setHost(String host) {
this.host = host;
}
public Integer getPort() {
return port;
}
public void setPort(Integer port) {
this.port = port;
}
public String getDatabase() {
return database;
}
public void setDatabase(String database) {
this.database = database;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Connection getConn() {
return conn;
}
public void setConn(Connection conn) {
this.conn = conn;
}
}
测试
public static void main(String[] args) {
Mysql8Instance m1 = new Mysql8Instance("127.0.0.1",3307,"test","root","123456");
System.out.println(m1.query("show tables;"));
m1.close();
Mysql8Instance m2 = new Mysql8Instance("127.0.0.1",3307,"sys","root","123456");
System.out.println(m2.query("show tables;"));
m2.close();
}mysql驱动
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.18</version>
</dependency>版权声明:本文为Lxinccode原创文章,遵循CC 4.0 BY-SA版权协议,转载请附上原文出处链接和本声明。