就很奇怪不知道为啥连接不上，我在dos窗口都可以连接，我加本机ip就是显示连接超时，用localhost就是直接打印下面的错误
```java
"C:\Program Files\Java\jdk-15.0.2\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2021.3\lib\idea_rt.jar=53419:C:\Program Files\JetBrains\IntelliJ IDEA 2021.3\bin" -Dfile.encoding=UTF-16 -classpath "F:\qf\out\production\qf;C:\Users\lucky chen\Desktop\软件\mysql-connector-java-8.0.27\mysql-connector-java-8.0.27.jar" JDBCtest01
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
com.mysql.cj.jdbc.exceptions.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 com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174)
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64)
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:828)
at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:448)
at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:198)
at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:677)
at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:228)
at JDBCtest01.main(JDBCtest01.java:21)
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: 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:64)
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.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.NativeProtocol.negotiateSSLConnection(NativeProtocol.java:317)
at com.mysql.cj.protocol.a.NativeAuthenticationProvider.connect(NativeAuthenticationProvider.java:203)
at com.mysql.cj.protocol.a.NativeProtocol.connect(NativeProtocol.java:1369)
at com.mysql.cj.NativeSession.connect(NativeSession.java:133)
at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:948)
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:818)
... 6 more
Caused by: javax.net.ssl.SSLException: Tag mismatch!
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:133)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:369)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:312)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:307)
at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:122)
at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1488)
at java.base/sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1394)
at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:441)
at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:412)
at com.mysql.cj.protocol.ExportControlled.performTlsHandshake(ExportControlled.java:335)
at com.mysql.cj.protocol.StandardSocketFactory.performTlsHandshake(StandardSocketFactory.java:194)
at com.mysql.cj.protocol.a.NativeSocketConnection.performTlsHandshake(NativeSocketConnection.java:101)
at com.mysql.cj.protocol.a.NativeProtocol.negotiateSSLConnection(NativeProtocol.java:308)
... 11 more
Caused by: javax.crypto.AEADBadTagException: Tag mismatch!
at java.base/com.sun.crypto.provider.GaloisCounterMode.decryptFinal(GaloisCounterMode.java:621)
at java.base/com.sun.crypto.provider.CipherCore.finalNoPadding(CipherCore.java:1118)
at java.base/com.sun.crypto.provider.CipherCore.fillOutputBuffer(CipherCore.java:1055)
at java.base/com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:943)
at java.base/com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:491)
at java.base/javax.crypto.CipherSpi.bufferCrypt(CipherSpi.java:794)
at java.base/javax.crypto.CipherSpi.engineDoFinal(CipherSpi.java:730)
at java.base/javax.crypto.Cipher.doFinal(Cipher.java:2500)
at java.base/sun.security.ssl.SSLCipher$T13GcmReadCipherGenerator$GcmReadCipher.decrypt(SSLCipher.java:1930)
at java.base/sun.security.ssl.SSLSocketInputRecord.decodeInputRecord(SSLSocketInputRecord.java:260)
at java.base/sun.security.ssl.SSLSocketInputRecord.decode(SSLSocketInputRecord.java:181)
at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:110)
... 19 more
进程已结束,退出代码0
###### 运行结果及报错内容
###### 我的解答思路和尝试过的方法
```java
import com.mysql.jdbc.Driver;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBCtest01 {
public static void main(String[] args) {
Connection connection = null;
Statement statement = null;
//1.注册驱动
try {
// Driver driver = new com.mysql.jdbc.Driver();
// DriverManager.deregisterDriver(driver);
Class.forName("com.mysql.jdbc.Driver");
//2.获取连接
String url = "jdbc:mysql://localhost:3306/bjpowernode";
String user = "root";
String password = "111111";
connection = DriverManager.getConnection(url,user,password);
System.out.println("数据库连接对象"+connection);
} catch (SQLException | ClassNotFoundException e) {
e.printStackTrace();
}
//2.获取连接
//3.获取数据库对象
//4.执行sql
//5.处理查询结果集
//6.释放资源
}
}
在url后面加上
?useSSL=false
注册驱动new驱动对象修改为
new com.mysql.cj.jdbc.Driver（）