Why is this ArrayList storing everything in first index? And how can one load image urls dynamically in JSP from that arraylist?

Question

Building a web application that uses google custom search API to fetch images related to the users search query. So if you search " cheese ", you will get back images that are cheese related.

Here is an example of what it currently looks like:

There are two main problems.

Why are all the query results being stored in the first index of my ArrayList? I only want one link for the moment.
How could i get these links to display images?

Currently there are three pieces of code for this. a JSP , a Servlet and a Java class.

DefineWord.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<%@ page import="googleAPI.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Define</title>

<link rel="stylesheet" type="text/css" href="css/bootstrap.css">

<link rel="stylesheet" href="css/bootstrap-lightbox.min.css">
<link rel="stylesheet" href="css/bootstrap-lightbox.css">

<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
<script src="js/includeNAV.js"></script>
<script type="text/javascript" src="https://www.google.com/jsapi"></script>

</head>
<body>



    <div id="includedNav"></div>


    <div class="container">
        <form id="searchForm" method="get" action="LinkServlet">
            <fieldset>

                <input id="s" type="text" name="query" /> <input type="submit"
                    value="Submit" id="submitButton" />


            </fieldset>
        </form>
    </div>
    <br />
<!--    Requests attributes from servlet -->

    <div class="container">
<%--        <%=request.getAttribute("links") %> --%>
        <br /> ONE LINK:
        <%=request.getAttribute("onelink") %>






    </div>
    <script
        src="//ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
    <script
        src="//blueimp.github.io/Gallery/js/jquery.blueimp-gallery.min.js"></script>
    <script src="js/bootstrap-image-gallery.min.js"></script>

</body>
</html>

LinkServlet.java

package googleAPI;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

    @WebServlet("/LinkServlet")
    public class LinkServlet extends HttpServlet {
        private static final long serialVersionUID = 1L;

        public LinkServlet() {
            super();
        }

        protected void doGet(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {

            // Get query from user through http parameter
            PrintWriter printWriter = response.getWriter();
            String query = request.getParameter("query");
            String results = google.psuedomain(query);

            // Put results string into a ArrayList so that the jsp can dynamically
            // call each image
            printWriter.println(results);
            String[] urlAry = results.split(" ");
            ArrayList<String> ar = new ArrayList<String>();
            for (int i = 0; i < urlAry.length; i++) {
                ar.add(urlAry[i]);
            }

            // Get first element from ArrayList and set attribute
            String onelink = ar.get(0);
            request.setAttribute("onelink", onelink);

            // Set query results to attribute so JSP can call it
            request.setAttribute("links", ar);

            // Forward request back to the same JSP.
            RequestDispatcher dispatcher = getServletContext().getRequestDispatcher("/DefineWord.jsp");
            dispatcher.forward(request, response);

        }

        protected void doPost(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {

        }

    }

google.java

package googleAPI;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.regex.Pattern;
import java.util.HashSet;
import java.util.Set;
import java.util.regex.Matcher;

public class google {
    static StringBuilder results = new StringBuilder();
    static String finalResults;

    public static String getFinalResults() {
        return finalResults;
    }

    public static void setFinalResults(String finalResults) {
        google.finalResults = finalResults;
    }

    public static String psuedomain(String qry) throws IOException {

        String key = "*********privatekey*********";
        URL url = new URL("https://www.googleapis.com/customsearch/v1?key=" + key
                + "&cx=*********privatekey*********&q=" + qry + "&alt=json");

        // CONNECTION LOGIC
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setRequestMethod("GET");
        conn.setRequestProperty("Accept", "application/json");
        BufferedReader br = new BufferedReader(new InputStreamReader((conn.getInputStream())));
        String output;
        while ((output = br.readLine()) != null) {
            Pattern pattern = Pattern.compile("(?:(?:https?)+\\:\\/\\/+[a-zA-Z0-9\\/\\._-]{1,})+(?:(?:jpe?g|png|gif))");
            Matcher matcher = pattern.matcher(output);
            if (matcher.find()) {
                results.append(matcher.group() + "\n");
            }

        }
        conn.disconnect();
        finalResults = removeDup();
        return finalResults;
    }

    public static String removeDup() {
        String[] tokens = results.toString().split("\n");
        StringBuilder resultBuilder = new StringBuilder();
        Set<String> alreadyPresent = new HashSet<String>();

        boolean first = true;
        for (String token : tokens) {

            if (!alreadyPresent.contains(token)) {
                if (first)
                    first = false;
                else
                    resultBuilder.append("\n");

                if (!alreadyPresent.contains(token))
                    resultBuilder.append(token + "\n");
            }

            alreadyPresent.add(token);
        }
        String result = resultBuilder.toString();
        return result;
    }

}

Any ideas? Thanks for your time.

Answer 1

In the LinkServlet.java file, the doGet method, you split the google.psuedomain answer with a space " ", but they where concatenated using a new line "\\n". So, either split on new line or change the concatenation to use a space. Even better, why don't you return an ArrayList of String with the google.psuedomain method ?

To display all the links as images, use a foreach block in which you add an img tag with the src attribute set to the current link.

Why is this ArrayList storing everything in first index? And how can one load image urls dynamically in JSP from that arraylist?

Question

1 answers

solution1
1 ACCPTED 2016-05-12 13:20:32

Why is this ArrayList storing everything in first index? And how can one load image urls dynamically in JSP from that arraylist?

Question

1 answers

solution1 1 ACCPTED 2016-05-12 13:20:32

solution1
1 ACCPTED 2016-05-12 13:20:32