今天在启动Springboot项目的时候连接数据库的时候报错了，错误信息如下:

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.	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.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:340)	at com.mysql.cj.protocol.a.NativeAuthenticationProvider.negotiateSSLConnection(NativeAuthenticationProvider.java:777)	at com.mysql.cj.protocol.a.NativeAuthenticationProvider.proceedHandshakeWithPluggableAuthentication(NativeAuthenticationProvider.java:486)	at com.mysql.cj.protocol.a.NativeAuthenticationProvider.connect(NativeAuthenticationProvider.java:202)	at com.mysql.cj.protocol.a.NativeProtocol.connect(NativeProtocol.java:1348)	at com.mysql.cj.NativeSession.connect(NativeSession.java:163)	at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:947)	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:817)	... 11 common frames omittedCaused by: javax.net.ssl.SSLHandshakeException: No appropriate protocol (protocol is disabled or cipher suites are inappropriate)

根据报错信息主要的原因就是 No appropriate protocol (protocol is disabled or cipher suites are inappropriate)，意思就是没有合适的协议，或者协议被禁用了，那么是什么协议被禁用了呢？根据SSLHandshakeException可以知道是SSL协议的问题，所以我的解决方案就是在连接jdbc的url上加上&useSSL=false,重新启动问题解决。

但是这个项目以前在我另外的电脑上运行的时候也是没有问题的，为什么我现在就出了问题了呢？原来是我两台电脑的jdk版本不一致导致的，打开现在电脑的java.security文件

cd /Library/Java/JavaVirtualMachines/jdk1.8.0_291.jdk/Contents/Home/jre/lib/security

可以看到ssl协议被禁用了

# Example:#   jdk.tls.disabledAlgorithms=MD5, SSLv3, DSA, RSA keySize < 2048jdk.tls.disabledAlgorithms=SSLv3, TLSv1, TLSv1.1, RC4, DES, MD5withRSA, \    DH keySize < 1024, EC keySize < 224, 3DES_EDE_CBC, anon, NULL, \    include jdk.disabled.namedCurves

修改一下删除SSL部分

# Example:#   jdk.tls.disabledAlgorithms=MD5, SSLv3, DSA, RSA keySize < 2048jdk.tls.disabledAlgorithms=RC4, DES, MD5withRSA, \    DH keySize < 1024, EC keySize < 224, 3DES_EDE_CBC, anon, NULL, \    include jdk.disabled.namedCurves

然后重启项目也能成功。