sailing-analytics/java/com.sap.sse/src/com/sap/sse/util/HttpUrlConnectionHelper.java

package com.sap.sse.util;

import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import com.sap.sse.common.Duration;

public class HttpUrlConnectionHelper {
    private static final int HTTP_MAX_REDIRECTS = 5;

    public static HttpURLConnection redirectConnection(URL url) throws MalformedURLException, IOException {
        HttpURLConnection connection = null;
        URL nextUrl = url;
        for (int counterOfRedirects = 0; counterOfRedirects <= HTTP_MAX_REDIRECTS; counterOfRedirects++) {
            if (connection != null) {
                connection.disconnect();
            }
            connection = (HttpURLConnection) nextUrl.openConnection();
            connection.setInstanceFollowRedirects(false);
            connection.setRequestProperty("User-Agent", "Mozilla/5.0...");
            connection.setDoOutput(true);
            // Initial timeout needs to be big enough to allow the first parts of the response to reach this server
            connection.setReadTimeout((int) Duration.ONE_MINUTE.times(10).asMillis());
            if (connection.getResponseCode() == HttpURLConnection.HTTP_MOVED_PERM
                    || connection.getResponseCode() == HttpURLConnection.HTTP_MOVED_TEMP) {
                String location = connection.getHeaderField("Location");
                nextUrl = new URL(nextUrl, location);
            } else {
                break;
            }
        }
        return connection;
    }

}