Java JDBC连接MySql数据库报错：Could not create connection to database server._could not create connection to database server. at

错误信息：

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.
	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.jdbc.Util.handleNewInstance(Util.java:377)
	at com.mysql.jdbc.Util.getInstance(Util.java:360)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:935)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:924)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:870)
	at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2311)
	at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2064)
	at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:790)
	at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
	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.jdbc.Util.handleNewInstance(Util.java:377)
	at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:395)
	at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
	at java.sql.DriverManager.getConnection(DriverManager.java:664)
	at java.sql.DriverManager.getConnection(DriverManager.java:247)
	at com.test.MySQLDemo.main(MySQLDemo.java:29)

测试代码：

package com.test;
 
import java.sql.*;
 
public class MySQLDemo {
	
	// MySQL 8.0  以下版本 - JDBC 驱动名及数据库 URL
//	static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
//	static final String DB_URL = "jdbc:mysql://localhost:3306/zhanghz";
	
	// MySQL 8.0 以上版本 - JDBC 驱动名及数据库 URL
	 static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
	 static final String DB_URL = "jdbc:mysql://localhost:3306/zhanghz?useSSL=false&serverTimezone=UTC";
	
	// 数据库的用户名与密码，需要根据的设置
	static final String USER = "root";
	static final String PASS = "123456";
 
	public static void main(String[] args) {
		Connection conn = null;
		Statement stmt = null;
		// 注册 JDBC 启动
		try {
			Class.forName(JDBC_DRIVER);
			
			// 打开链接
			System.out.println("连接数据库...");
			conn = DriverManager.getConnection(DB_URL,USER,PASS);
			
			// 执行查询
			System.out.println("实例化Statement对象...");
			stmt = conn.createStatement();
			String sql;
			sql = "SELECT id, name, url FROM websites";
			ResultSet rs = stmt.executeQuery(sql);
			
			// 展开结果集数据库
			while(rs.next()){
				// 通过字段检索
				int id = rs.getInt("id");
				String name = rs.getString("name");
				String url = rs.getString("url");
				
				//输出数据
				System.out.print("ID：" + id);
				System.out.print("，站点名称：" + name);
				System.out.print("，站点URL：" + url);
				System.out.print("\n");
			}
			// 完成后关闭
			rs.close();
			stmt.close();
			conn.close();
		} catch (SQLException e) {
			// 处理 JDBC 错误
			e.printStackTrace();
		} catch (Exception e) {
			// 处理 Class.forName 错误
			e.printStackTrace();
		} finally {
			// 关闭资源
			try {
				if(stmt != null) conn.close();
			} catch (SQLException e2) {
				// 什么都不做
			}
			try {
				if(conn != null) conn.close();
			} catch (SQLException se) {
				se.printStackTrace();
			}
		}
		System.out.println("Goodbye!");
	}
 
}

数据库信息：

pom.xml配置：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.zhanghz</groupId>
  <artifactId>connectdatabase</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <dependencies>
  	<dependency>
  		<groupId>mysql</groupId>
  		<artifactId>mysql-connector-java</artifactId>
  		<version>5.1.34</version>
  	</dependency>
  </dependencies>
</project>

解决办法和分析：

因为本地的MySQL数据库是8.0以上的版本，而Java引用的驱动jar包版本为5.1.34，导致出现上面的报错：Could not create connection to database server.

把Java引用的驱动器jar包版本改为8.0以上的就不会再出现上面的问题。

文档的解决方法仅供参考，具体的问题具体分析。