Java Requires Chilkat v11.0.0+

REST Follow Redirects

See more REST Examples

Demonstrates how to follow a 302/303 redirect response. Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Rest;
import com.chilkatsoft.chilkat2.Url;

public class ChilkatExample {

    public static void main(String[] args) {
        // This example requires the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        Rest rest = new Rest();

        boolean bTls = true;
        int port = 443;
        boolean bAutoReconnect = true;
        String responseText;
        try {
            rest.connect("chilkatsoft.com", port, bTls, bAutoReconnect);

            // Send a POST to a URL that will respond with a 302 redirect..
            rest.addQueryParam("firstName", "John");
            rest.addQueryParam("lastName", "Doe");
            responseText = rest.fullRequestFormUrlEncoded("POST", "/echoPost302.asp");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        int statusCode = rest.getResponseStatusCode();

        // Examine the response status code
        if (statusCode < 300) {
            System.out.println("Not a redirect.");
            System.out.println(responseText);
            return;
        }

        if (statusCode > 399) {
            System.out.println("Error response: Status code = " + statusCode);
            System.out.println(responseText);
            return;
        }

        System.out.println("Redirect status code = " + statusCode);

        // The response header will contain a Location field with the redirect URL, such as this:
        // Location: http://www.chilkatsoft.com/echoPostFinal.asp

        // The response status code determines how the client should behave.
        // Here are some common possibilities:

        // 301: Moved Permanently
        // This and all future requests should be directed to the given URI.  (Keep the original HTTP method for the redirect.  In this case, the
        // original request was a POST, so we POST to the redirect URL.)

        // 302: Found (aka Object Moved aka Moved Temporarily)
        // This is the most popular redirect code, but also an example of industrial practice contradicting the standard. HTTP/1.0 specification (RFC 1945 ) required the client
        // to perform a temporary redirect (the original describing phrase was �Moved Temporarily�), but popular browsers implemented it as a 303 See Other. Therefore, HTTP/1.1
        // added status codes 303 and 307 to disambiguate between the two behaviors. However, the majority of Web applications and frameworks still use the 302 status code
        // as if it were the 303.

        // 303: See Other
        // The response to the request can be found under another URI using a GET method. When received in response to a PUT, it should be assumed that the server has
        // received the data and the redirect should be issued with a separate GET message.

        // 307: Temporary Redirect
        // In this occasion, the request should be repeated with another URI, but future requests can still use the original URI. In contrast to 303, the request method
        // should not be changed when reissuing the original request. For instance, a POST request must be repeated using another POST request.

        System.out.println(rest.getResponseHeader());

        // Get the redirect URL
        String urlStr = rest.getLastRedirectUrl();
        if (!rest.getLastMethodSuccess()) {
            System.out.println("No Location header found for redirect.");
            return;
        }

        Url redirectUrl = new Url();
        redirectUrl.parseUrl(urlStr);

        // Prep for the redirect..
        rest.clearAllParts();

        // Disconnect and re-connect.
        // (This can be skipped if both the host and SSL/TLS conditions are the same.)
        rest.disconnect(100);
        try {
            rest.connect(redirectUrl.getHost(), redirectUrl.getPort(), redirectUrl.getSsl(), bAutoReconnect);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        if ((statusCode == 301) || (statusCode == 307)) {
            // Redirect using a POST, sending the same params to the new destination
            rest.addQueryParam("firstName", "John");
            rest.addQueryParam("lastName", "Doe");
            try {
                responseText = rest.fullRequestFormUrlEncoded("POST", redirectUrl.getPath());
            } catch (ChilkatException e) {
                System.out.println(e.getLastErrorText());
                return;
            }
        }

        if ((statusCode == 302) || (statusCode == 303)) {
            // Redirect using a GET, sending the query params found in the redirect URL.
            try {
                responseText = rest.fullRequestFormUrlEncoded("GET", redirectUrl.getPathWithQueryParams());
            } catch (ChilkatException e) {
                System.out.println(e.getLastErrorText());
                return;
            }
        }

        // Show the final status code and the response text.
        System.out.println("Final status code = " + rest.getResponseStatusCode());

        System.out.println("Final response text (HTML, XML, JSON, or whatever..)");
        System.out.println(responseText);
    }
}