(Java) Manually Follow HTTP Redirects

Demonstrates how to manually follow redirects for an HTTP GET.

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

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

    CkHttp http = new CkHttp();

    // The FollowRedirects property controls whether redirects
    // are automatically followed.  The default behavior is to
    // automatically follow redirects.

    // Explicitly set FollowRedirects so that redirects are NOT automatically taken:
    http.put_FollowRedirects(false);

    CkHttpResponse resp = http.QuickGetObj("http://yandex.ru/");
    if (http.get_LastMethodSuccess() == false) {
        System.out.println(http.lastErrorText());
        return;
        }

    int status = resp.get_StatusCode();
    System.out.println("HTTP Response Status: " + status);

    // The FinalRedirectUrl property will contain the redirect URL
    // If FollowRedirects was equal to true, then all of the 
    // intermediate redirects (if any) would be followed until
    // there were no more redirects.  However, because 
    // FollowRedirects is not true, FinalRedirectUrl contains
    // the next redirect URL.

    int loopCount = 0;

    while ((status == 302)) {

        // IMPORTANT: This example requires Chilkat v9.5.0.49 or greater because
        // the FinalRedirectUrl in prior versions is only set when redirects
        // are automatically followed.   Starting in v9.5.0.49, the FinalRedirectUrl is
        // set to the next redirect URL when a 301/302 response is received, regardless
        // of the value of the FollowRedirects property.
        System.out.println("Redirect URL: " + http.finalRedirectUrl());

        String nextUrl = http.finalRedirectUrl();
        resp = http.QuickGetObj(nextUrl);
        if (http.get_LastMethodSuccess() == false) {
            System.out.println(http.lastErrorText());
            return;
            }

        status = resp.get_StatusCode();
        System.out.println("HTTP Response Status: " + status);

        // For safety, prevent infinite loops by
        // keeping a loopCount and only allows following a max 
        // of 10 redirects:
        loopCount = loopCount+1;
        if (loopCount > 10) {

            System.out.println("Too many redirects.");
            return;
            }

        }
  }
}