com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:990)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:335)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2187)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2220)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2015)
at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:768)
at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:47)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323)
at org.mybatis.generator.internal.db.ConnectionFactory.getConnection(ConnectionFactory.java:68)
at org.mybatis.generator.config.Context.getConnection(Context.java:526)
at org.mybatis.generator.config.Context.introspectTables(Context.java:436)
at org.mybatis.generator.api.MyBatisGenerator.generate(MyBatisGenerator.java:222)
at org.mybatis.generator.api.MyBatisGenerator.generate(MyBatisGenerator.java:133)
Caused by: java.net.ConnectException: Connection refused: connect
at java.base/sun.nio.ch.Net.connect0(Native Method)
at java.base/sun.nio.ch.Net.connect(Net.java:493)
at java.base/sun.nio.ch.Net.connect(Net.java:482)
at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:588)
at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:339)
at java.base/java.net.Socket.connect(Socket.java:603)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:211)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:299)
看看是不是相关数据库本地服务没开启，或者是相关配置文件的数据库账号密码写错
