有关数据库版本和URL安全的问题:

以下是报错..

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 1,567 milliseconds ago. The last packet sent successfully to the server was 1,567 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:4914)
​	at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1663)
​	at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224)
​	at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199)
​	at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230)
​	at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025)
​	at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778)
​	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:386)
​	at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
​	at java.sql.DriverManager.getConnection(DriverManager.java:664)
​	at java.sql.DriverManager.getConnection(DriverManager.java:247)
​	at com.wang.service.user.UserServiceImpl.test(UserServiceImpl.java:42)
​	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
​	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
​	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
​	at java.lang.reflect.Method.invoke(Method.java:498)
​	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
​	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
​	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
​	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
​	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
​	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
​	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
​	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
​	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
​	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
​	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
​	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
​	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
​	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
​	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
​	at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
​	at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:230)
​	at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58)
Caused by: ![img](file:///C:\Users\ASUS\AppData\Roaming\Tencent\QQTempSys\%W@GJ$ACOF(TYDYECOKVDYB.png)javax.net.ssl.SSLHandshakeException: java.security.cert.CertificateException: java.security.cert.CertPathValidatorException: Path does not chain with any of the trust anchors

解决方法:

对于数据库使用5.7以上版本的
    useSSL=false

下面这个箭头指的地方改成 false

对于数据库使用5.7以下的版本的 比如5.6.44x
useSSL=true