Cannot open Eclipse Marketplace

1、运行eclipse的时候，想升级一下插件，一直不能连接网络，报错

错误：

Cannot open Eclipse Marketplace

Cannot install remote marketplace locations: Connection failed

This is most often caused by a problem with your internet connection.Please check your internet connection and retry.

Unable to read repository athttp://marketplace.eclipse.org/catalogs/api/p.

Connection reset

Connection failed

This is most often caused by a problem with your internet connection.Please check your internet connection and retry.

Connection reset

解决办法

找来找去没找到解决办法，在stackoverflow中http://stackoverflow.com/questions/19080752/unable-to-open-eclipse-marketplace终于看到描述，在eclipse.ini中增加

-Djava.net.preferIPv4Stack=true