【数据库错误】Could not create connection to database server. Attempted reconnect 3 times. Giving up.

错误日志： java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:110) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) 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.newInstance(Constructor.java:490) at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105) at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151) at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:167) at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:91) at com.mysql.cj.NativeSession.connect(NativeSession.java:152) 原因： 错误日志： java.sql.SQLNonTransientConnectionException