两种可能性
1. 你的/usr/lib/jvm/java-8-openjdk-amd64/bin/java是个软链接
那么这样可解决
sudo setcap cap_net_bind_service=+ep `readlink -f /usr/lib/jvm/java-8-openjdk-amd64/bin/java`
2. 你的 /usr/lib/jvm/java-8-openjdk-amd64/bin/java 是个shell文件
cat /usr/lib/jvm/java-8-openjdk-amd64/bin/java 看下世纪执行的java二进制文件的真路径,然后对真路径的java程序执行cap_net_bind_service


中文 
根据网上一些其他的介绍,root用户尝试使用setcap setcap cap_net_bind_service,但是报下面的错误,/usr/lib/jvm/java-8-openjdk-amd64/bin/java是我的java执行程序
setcap cap_net_bind_service=+ep /usr/lib/jvm/java-8-openjdk-amd64/bin/java
Failed to set capabilities on file `/usr/lib/jvm/java-8-openjdk-amd64/bin/java' (Invalid argument)
The value of the capability argument is not permitted for a file. Or the file is not a regular (non-symlink) file