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Caused by: java.net.SocketException: Permission denied: connect

环境：JDK1.8、IDEA开发工具、

情况：在一台电脑上的IDEA可运行该项目，在另外一台则不行了，还报错了。

报错内容：

2022-06-29 15:57:02.096 ERROR 3928 --- [eate-1221387328] com.alibaba.druid.pool.DruidDataSource   : create connection SQLException, url: jdbc:mysql://192.168.129.1:3306/subjectresmgr?useSSL=false&useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true&serverTimezone=GMT%2B8, errorCode 0, state 08S01

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:836)
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456)
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246)
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:198)
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1652)
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1718)
	at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2785)
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 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.NativeSocketConnection.connect(NativeSocketConnection.java:89)
	at com.mysql.cj.NativeSession.connect(NativeSession.java:144)
	at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:956)
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:826)
	... 6 common frames omitted
Caused by: java.net.SocketException: Permission denied: connect
	at java.net.DualStackPlainSocketImpl.connect0(Native Method)
	at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79)
	at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
	at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
	at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
	at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
	at java.net.Socket.connect(Socket.java:589)
	at com.mysql.cj.protocol.StandardSocketFactory.connect(StandardSocketFactory.java:155)
	at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:63)
	... 9 common frames omitted

数据库通过Navicat可以连接使用，用IDEA的Database也可以连接使用，就是启动的时候，连接出问题。

因为是Springboot项目，内置Tomcat，所以网上查的

1、配置-Djava.net.preferIPv4Stack=true启动Tomcat

2、配置环境变量：JAVA_OPTS 值为：-Djava.net.preferIPv4Stack=true

这些其实都没有作用，不过提供了一个思路，可以配置SpringBoot启动器的VM options

解决方式一：

在Environment中，配置VM options值为-Djava.net.preferIPv4Stack=true

解决方式二：

同样修改SpringBoot的启动器，将JRE版本修改成JDK11试试