mysql8.0之caching_sha2_password

java.sql.SQLException: Unable to load authentication plugin 'caching_sha2_password'.
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:868) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:864) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1746) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1226) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2191) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2222) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2017) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:779) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_77]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_77]
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_77]
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_77]
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389) ~[mysql-connector-java-5.1.44.jar:5.1.44]
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) ~[mysql-connector-java-5.1.44.jar:5.1.44]

该异常原因是：在mysql8之前的版本使用的密码加密规则是mysql_native_password，但是在mysql8则是caching_sha2_password。

解决方案：

一、创建了一个新用户，并指定加密规则为mysql_native_password：

 

CREATE USER  'your username'@'%' IDENTIFIED WITH mysql_native_password BY 'your password;

或者修改用户加密方式

 ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'root';

二、将默认密码规则设置为mysql_native_password，刷新权限并重置root密码。

default_authentication_plugin=mysql_native_password

三、针对java引入新的mysql-connector-java包，并将驱动改为com.mysql.cj.jdbc.Driver。