今天eclipse连接mysql遇到不少问题。

我用的环境如下（错误的情况下）：

 eclipse 4.7；

jdk1.7（Java project）；

mysql5.6；

mysql-connector-java-8.0.12.jar(需要导入)；

部分连接语句（错误的部分）：

 String driver = "com.mysql.jdbc.Driver";
 String url = "jdbc:mysql://localhost:3306/test ";

 

1 版本错误：Unsupported major.minor version 52.0

JDK版本在官方对应的版本号列表如下(引用https://blog.csdn.net/zixiao217/article/details/52818658)：

此错误将

JDK 8.0 = 52,
JDK 7.0 = 51,
JDK 6.0 = 50,
JDK 5.0 = 49,
JDK 1.4 = 48,
JDK 1.3 = 47,
JDK 1.2 = 46,
JDK 1.1 = 45

 将jdk 修改成1.8后这个错误消失

2 连接驱动driver错误

错误提示：

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.

加入‘cj.’修改为此错误消失：

 String driver = "com.mysql.cj.jdbc.Driver";

3  时区没有设置

错误提示：

java.sql.SQLException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129)
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89)
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63)
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73)
	at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:76)
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:832)
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456)
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240)
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:207)
	at java.sql.DriverManager.getConnection(DriverManager.java:664)
	at java.sql.DriverManager.getConnection(DriverManager.java:247)
	at mysqljdbc1217.main.main(main.java:29)
Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61)
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:85)
	at com.mysql.cj.util.TimeUtil.getCanonicalTimezone(TimeUtil.java:128)
	at com.mysql.cj.protocol.a.NativeProtocol.configureTimezone(NativeProtocol.java:2236)
	at com.mysql.cj.protocol.a.NativeProtocol.initServerSession(NativeProtocol.java:2260)
	at com.mysql.cj.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:1314)
	at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:963)
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:822)
	... 6 more

修改 ：

String url = "jdbc:mysql://localhost:3306/test "+ "?serverTimezone=GMT%2B8";
         

错误全部消失。

全部代码如下：

package mysqljdbc1217;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
 
 public class main {
 
     public static void main(String[] args) {
         //声明Connection对象
         Connection con;
         //驱动程序名
         String driver = "com.mysql.cj.jdbc.Driver";
         //URL指向要访问的数据库名mydata
         String url = "jdbc:mysql://localhost:3306/test "+ "?serverTimezone=GMT%2B8";
         //MySQL配置时的用户名
         String user = "root";
         //MySQL配置时的密码
         String password = "11111";
         //遍历查询结果集
         try {
             //加载驱动程序
        	   System.out.println("执行结果如下所示:"); 
             Class.forName(driver);
             System.out.println("执行结果如下所示:"); 
             //1.getConnection()方法，连接MySQL数据库！！
             con = DriverManager.getConnection(url,user,password);
             if(!con.isClosed())
                 System.out.println("Succeeded connecting to the Database!");
             //2.创建statement类对象，用来执行SQL语句！！
             Statement statement = con.createStatement();
             //要执行的SQL语句
             String sql = "select * from temporpary_data";
             //3.ResultSet类，用来存放获取的结果集！！
             ResultSet rs = statement.executeQuery(sql);
             System.out.println("-----------------");
             System.out.println("执行结果如下所示:");  
             System.out.println("-----------------");  
             System.out.println("姓名" + "\t" + "职称");  
             System.out.println("-----------------");  
              
             String job = null;
             String id = null;
           /*  while(rs.next()){
                 //获取stuname这列数据
                 job = rs.getString("job");
                 //获取stuid这列数据
                 id = rs.getString("ename");
 
                 //输出结果
                 System.out.println(id + "\t" + job);
             }
             rs.close();
             con.close();*/
         } catch(ClassNotFoundException e) {   
             //数据库驱动类异常处理
             System.out.println("Sorry,can`t find the Driver!");   
             e.printStackTrace();   
             } catch(SQLException e) {
             //数据库连接失败异常处理
             e.printStackTrace();  
            }catch (Exception e) {
             // TODO: handle exception
             e.printStackTrace();
         }finally{
             System.out.println("数据库数据成功获取！！");
         }
     }
 
}