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構建web應用程序用戶可以在其中搜索單詞並返回相關圖像。但是，只要查詢被更改，圖像不會。這裏發生了什麼？JSP中不刷新的圖像java動態web項目
用戶搜索「貓」並返回圖像。但是在第一次查詢之後就會保持這種狀態。 
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>
<style>
.fit_image img {
max-width: 100%;
max-height: 100%;
}
.fit_image {
width: 400px;
height: 200px;
}
</style>
</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:
<div class="fit_image">
<img src="<%=request.getAttribute("onelink")%>"/>
</div>
</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.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 {
request.removeAttribute("onelink");
// Get query from user through http parameter
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
String[] urlAry = results.split("\n");
ArrayList<String> ar = new ArrayList<String>();
ar.clear();
ar.removeAll(ar);
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 = "*********private key************";
URL url = new URL("https://www.googleapis.com/customsearch/v1?key=" + key
+ "&cx=*********private key************&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;
}
}
關於這可能發生的原因的任何想法？謝謝你的時間。