[root@host73 ~]# java -version
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)
[root@host73 ~]# javac -version
javac 1.8.0_111

yum install -y java-1.7.0-openjdk.x86_64 java-1.7.0-openjdk-devel.x86_64

export JAVA_HOME=/usr/lib/jdk1.8.0_111

export JAVA_HOME=/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.261-2.6.22.2.el7_8.x86_64

[root@host73 ~]# which java
/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.261-2.6.22.2.el7_8.x86_64/bin/java
[root@host73 ~]# which javac
/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.261-2.6.22.2.el7_8.x86_64/bin/javac

[root@host74 java]# java -version
java version "1.7.0_261"
OpenJDK Runtime Environment (rhel-2.6.22.2.el7_8-x86_64 u261-b02)
OpenJDK 64-Bit Server VM (build 24.261-b02, mixed mode)
[root@host74 java]# javac -version
javac 1.7.0_261

mysqld --version
/usr/local/mysql-8.0.26-linux-glibc2.17-x86_64-minimal-rebuild/bin/mysqld  Ver 8.0.26 for Linux on x86_64 (MySQL Community Server - GPL)

create database testdb;
create user testuser identified with mysql_native_password by 'testpass';
grant all on testdb.* to testuser;

use testdb;

CREATE TABLE `dbinfo` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` char(20) NOT NULL DEFAULT '' COMMENT 'dbinfo',
  `website` varchar(255) NOT NULL DEFAULT 'website',
  `opensource` varchar(2) NOT NULL DEFAULT '0' COMMENT 'is opensource',
  `country` char(10) NOT NULL DEFAULT '' COMMENT 'country',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB ;

insert into dbinfo values('1','Oracle','www.oracle.com','否','美國');
insert into dbinfo values('2','MySQL','www.mysql.com','是','美國');
insert into dbinfo values('3','GreatSQL','www.greatsql.com','是','中國');

import java.sql.*;

public class ShowDbinfo {

    // MySQL 8.0 以下版本 - JDBC 驅動名及數(shù)據(jù)庫 URL
    static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
    static final String DB_URL = "jdbc:mysql://172.17.128.73:16315/testdb?useSSL=false";

    // MySQL 8.0 以上版本 - JDBC 驅動名及數(shù)據(jù)庫 URL
    //static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";  
    //static final String DB_URL = "jdbc:mysql://172.17.128.73:16310/testdb?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC";


    // 數(shù)據(jù)庫的用戶名與密碼，需要根據(jù)自己的設置
    static final String USER = "testuser";
    static final String PASS = "testpass";

    public static void main(String[] args) {
        Connection conn = null;
        Statement stmt = null;
        try{
            // 注冊 JDBC 驅動
            Class.forName(JDBC_DRIVER);

            // 打開鏈接
            System.out.println("開始連接數(shù)據(jù)庫...");
            conn = DriverManager.getConnection(DB_URL,USER,PASS);

            // 執(zhí)行查詢
            stmt = conn.createStatement();
            String sql;
            sql = "SELECT id, name, website,opensource,country FROM dbinfo";
            ResultSet rs = stmt.executeQuery(sql);

            // 展開結果集數(shù)據(jù)庫
            while(rs.next()){
                // 通過字段檢索
                int id  = rs.getInt("id");
                String name = rs.getString("name");
                String website = rs.getString("website");
                String opensource = rs.getString("opensource");
                String country = rs.getString("country");
                // 輸出數(shù)據(jù)
                System.out.print("ID: " + id);
                System.out.print(", 名稱: " + name);
                System.out.print(", website: " + website);
                System.out.print(", 開源: " + opensource);
                System.out.print(", 來自: " + country);
                System.out.print("\n");
            }
            // 完成后關閉
            rs.close();
            stmt.close();
            conn.close();
        }catch(SQLException se){
            se.printStackTrace();
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            try{
                if(stmt!=null) stmt.close();
            }catch(SQLException se2){
            }
            try{
                if(conn!=null) conn.close();
            }catch(SQLException se){
                se.printStackTrace();
            }
        }
        System.out.println("Goodbye!");
    }
}

javac -cp .:mysql-connector-java-5.1.46.jar ShowDbinfo.java

java -cp .:mysql-connector-java-5.1.46.jar ShowDbinfo