老师我这个是什么问题为啥链接失败 Tue Nov 07 04:20:51 CST 2023 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification. Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 782 milliseconds ago. The last packet sent successfully to the server was 774 milliseconds ago. 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:425) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:990) at com.mysql.jdbc.ExportControlled.transformSocketToSSLSocket(ExportControlled.java:201) at com.mysql.jdbc.MysqlIO.negotiateSSLConnection(MysqlIO.java:4869) at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1656) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1217) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2189) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2220) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2015) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:768) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) 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:425) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at java.sql.DriverManager.getConnection(DriverManager.java:664) at java.sql.DriverManager.getConnection(DriverManager.java:247) at jdbcTest.main(jdbcTest.java:22) Caused by: javax.net.ssl.SSLHandshakeException: No appropriate protocol (protocol is disabled or cipher suites are inappropriate) at sun.security.ssl.HandshakeContext.<init>(HandshakeContext.java:171) at sun.security.ssl.ClientHandshakeContext.<init>(ClientHandshakeContext.java:101) at sun.security.ssl.TransportContext.kickstart(TransportContext.java:238) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:394) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:373) at com.mysql.jdbc.ExportControlled.transformSocketToSSLSocket(ExportControlled.java:186) ... 18 more