sun.net.www.protocol.http.HttpURLConnection.java 中一段很搞的代码。 内部匿名类无法访问外面的非 final 的变量。这里用数组的形式进行 workaround

sun.net.www.protocol.http.HttpURLConnection.java

final boolean result[] = {false};
java.security.AccessController.doPrivileged(new java.security.PrivilegedAction() {
    public Object run() {
        try {
            InetAddress a1 = InetAddress.getByName(h1);
            InetAddress a2 = InetAddress.getByName(h2);
            result[0] = a1.equals(a2);
        } catch (UnknownHostException e) {
        } catch (SecurityException e) {
        }
        return null;
    }
});

return result[0];