Question

我有一个简单的程序只是从包含大量URL（准确地说是1,975）的文本文件中读取，为了测试它，我创建了一个小得多的文件，其中只有3个URL。我已经能够捕获重定向正在发生（使用connection.setInstanceFollowRedirects(false);）并且它完美地工作并返回我期望看到的302.

我想看到的是它成功重定向的目标网址 我该怎么做？我刚刚编辑过来尝试我在这里看到的其他一些东西，但它没有返回重定向的URL，只是相同的原始URL预重定向.....

这是我的观赏乐趣

（请原谅你看到的任何明显的无知，我仍然是JAVA的新手）：

import java.util.*;
import java.io.*;
import java.nio.file.*;
import java.nio.charset.*;
import java.net.*;
//import java.security.cert.*;

public class URL_Tester {

    Charset charset = Charset.forName("US-ASCII");
    //Path file = Paths.get("url_list_small.txt"); // COMMENT OUT THIS LINE, AND UNCOMMENT OUT THE NEXT LINE TO SEE IT WORK
    Path file = Paths.get("url_list_working.txt");
    private BufferedReader reader;
    //private BufferedWriter writer;
    private ArrayList<String> urls;
    private URL url;

    public static void main(String[] args) {
        URL_Tester tester = new URL_Tester();
        tester.getArry();
        //tester.printArry();
        tester.getConnected();
    } // end of main METHOD

    /* 
    * The Method Below simply reads from a text file, and populates an ArrayList of Strings
    * The text file is meant to contain URLs for testing
    */
    public void getArry() {
        urls = new ArrayList<String>();
        String line = null;
        //System.out.println(file.toString());
        try {
            reader = Files.newBufferedReader(file, charset);
            while ((line = reader.readLine()) != null) {
                urls.add(line);
            }
        }
        catch (IOException ex) {
            System.out.println(ex);
        }
    } // end of getArry METHOD

    /* 
    * The Method below simply prints out the contents of the ArrayLlist to the console (for testing purposes) 
    */
    public void printArry() {
        System.out.println(" ");
        for (int i = 0; i < urls.size(); i++) {
            System.out.println(urls.get(i));
        }
    } // end printArry METHOD

    /* 
    * The Method below loops through the ArrayList of URL strings it attempts to make HTTP connection to each URL provided 
    */
    public void getConnected() {
        int code;
        for (int i = 0; i < urls.size(); i++) {
            try {
                url = new URL(urls.get(i));
            }
            catch (MalformedURLException ex) {
                System.out.println("\n*********** MalformedURLException area ********************");
                ex.printStackTrace();
            }
            try {
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setRequestMethod("GET");
            connection.setInstanceFollowRedirects(false);
            //connection.connect(); // AT THIS LINE AN IOException IS THROWN
            //sample code begins here
            System.out.println( "orignal url: " + connection.getURL() );
            connection.connect();
            System.out.println( "connected url: " + connection.getURL() );
            InputStream is = connection.getInputStream();
            System.out.println( "redirected url: " + connection.getURL() );
            is.close();
            // sample code ends here
            code = connection.getResponseCode();
            System.out.println(urls.get(i) + " code == " + code);

        }
            catch (Exception ix) {
                System.out.println("\n***************  IOException area ************************");
                ix.printStackTrace();
                break;
            }
        } // end LOOP
    } // end getConnected METHOD
} // end CLASS

捕获重定向目标JAVA

0 个答案: