How to Set the User Agent of a Java URLConnection Without Java Additions?

Setting the User Agent of a Java URLConnection Without Java Addition

In Java, setting the User-Agent property of a URLConnection typically adds "Java/version" to the end of the agent string specified. To achieve a pure user-specified User-Agent, the following steps are necessary:

Java 1.6.30 and Later

In Java versions 1.6.30 and later, setRequestProperty("User-Agent", "user-agent-string") sets the agent without Java addition. This can be confirmed by listening for incoming requests with a port listener like netcat:

$ nc -l -p 8080

Without setRequestProperty, the headers will look like this:

GET /foobar HTTP/1.1
User-Agent: Java/1.6.0_30
Host: localhost:8080
Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2
Connection: keep-alive

With setRequestProperty, the User-Agent will be correctly set:

GET /foobar HTTP/1.1
User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.4; en-US; rv:1.9.2.2) Gecko/20100316 Firefox/3.6.2
Host: localhost:8080
Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2
Connection: keep-alive

Full Example:

import java.io.IOException;
import java.net.URL;
import java.net.URLConnection;

public class TestUrlOpener {

    public static void main(String[] args) throws IOException {
        URL url = new URL("http://localhost:8080/foobar");
        URLConnection hc = url.openConnection();
        hc.setRequestProperty("User-Agent", "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.4; en-US; rv:1.9.2.2) Gecko/20100316 Firefox/3.6.2");

        System.out.println(hc.getContentType());
    }

}

The above is the detailed content of How to Set the User Agent of a Java URLConnection Without Java Additions?. For more information, please follow other related articles on the PHP Chinese website!