堆栈跟踪：

Exception in thread "main" java.sql.SQLNonTransientConnectionException: Public Key Retrieval is not allowed at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:108) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:95) at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122) at 
 com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:862) at com.mysql.cj.jdbc.ConnectionImpl.(ConnectionImpl.java:444) at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:230) at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:226) at com.mysql.cj.jdbc.MysqlDataSource.getConnection(MysqlDataSource.java:438) at com.mysql.cj.jdbc.MysqlDataSource.getConnection(MysqlDataSource.java:146) at com.mysql.cj.jdbc.MysqlDataSource.getConnection(MysqlDataSource.java:119) at ConnectionManager.getConnection(ConnectionManager.java:28) at Main.main(Main.java:8)

连接代码：

public class ConnectionManager {

    public static final String serverTimeZone = "UTC";
    public static final String serverName = "localhost";
    public static final String databaseName ="mysqldb";
    public static final int portNumber = 3306;
    public static final String user = "anyroot";
    public static final String password = "anyroot";

    public static Connection getConnection() throws SQLException {

        MysqlDataSource dataSource = new MysqlDataSource();

        dataSource.setUseSSL( false );
        dataSource.setServerTimezone( serverTimeZone );
        dataSource.setServerName( serverName );
        dataSource.setDatabaseName( databaseName );
        dataSource.setPortNumber( portNumber );
        dataSource.setUser( user );
        dataSource.setPassword( password );

        return dataSource.getConnection();
    }
}

解决异常问题

解决此异常问题需要将allowPublicKeyRetrieval=true和useSSL=false。

1）通过代码设置

dataSource.setAllowPublicKeyRetrieval(true);
dataSource.setUseSSL(false);

2）jdbc的url设置

jdbc:mysql://localhost:3306/Database_dbName?allowPublicKeyRetrieval=true&useSSL=false;

3）Spring boot配置

spring.datasource.url=jdbc:mysql://localhost:3306/db-name?useUnicode=true&characterEncoding=UTF-8&allowPublicKeyRetrieval=true&useSSL=false
spring.datasource.username=root
spring.datasource.password=root