在连接到代理后面的URL之前添加此选项。

System.getProperties().put("http.proxyHost", "someProxyURL");
System.getProperties().put("http.proxyPort", "someProxyPort");
System.getProperties().put("http.proxyUser", "someUserName");
System.getProperties().put("http.proxyPassword", "somePassword");

如果你想要“Socks Proxy”，通知“socksProxyHost”和“socksProxyPort”虚拟机参数。

e.g.

java -DsocksProxyHost=127.0.0.1 -DsocksProxyPort=8080 org.example.Main

这对我来说很管用:

public void setHttpProxy(boolean isNeedProxy) {
    if (isNeedProxy) {
        System.setProperty("http.proxyHost", getProxyHost());
        System.setProperty("http.proxyPort", getProxyPort());
    } else {
        System.clearProperty("http.proxyHost");
        System.clearProperty("http.proxyPort");
    }
}

P/S:我基于GHad的回答。

You can utilize the http.proxy* JVM variables if you're within a standalone JVM but you SHOULD NOT modify their startup scripts and/or do this within your application server (except maybe jboss or tomcat). Instead you should utilize the JAVA Proxy API (not System.setProperty) or utilize the vendor's own configuration options. Both WebSphere and WebLogic have very defined ways of setting up the proxies that are far more powerful than the J2SE one. Additionally, for WebSphere and WebLogic you will likely break your application server in little ways by overriding the startup scripts (particularly the server's interop processes as you might be telling them to use your proxy as well...).

将usesystemagents属性设置为true。例如，您可以通过JAVA_TOOL_OPTIONS环境变量来设置它。例如，在Ubuntu中，你可以在.bashrc中添加以下代码行:

export JAVA_TOOL_OPTIONS+=" - djava.net.usesystemagents =true"

综合Sorter和javabrett/Leonel的回答:

java -Dhttp.proxyHost=10.10.10.10 -Dhttp.proxyPort=8080 -Dhttp.proxyUser=username -Dhttp.proxyPassword=password -jar myJar.jar