这是将字符串转换为列表的正确方法吗?Java - 将字符串转换为列表
List styles = (List)request.getParameter("styles");
Model (BeerExpert.java)
package com.example.model;
import java.util.*;
public class BeerExpert {
public List getBrands(String color){
List brands = new ArrayList();
if(color.equals("amber")){
brands.add("Jack Amber");
brands.add("Red Moose");
}
else{
brands.add("Jail Pale Ale");
brands.add("Gout Scott");
}
return brands;
}
}
下一个是servlet类
BeerSelect.java
package com.example.web;
import com.example.model.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
public class BeerSelect extends HttpServlet {
public void doPost(HttpServletRequest request,
HttpServletResponse response)
throws IOException,ServletException{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("Beer Selection Advice <br>");
String c = request.getParameter("color");
BeerExpert be = new BeerExpert();
List result = be.getBrands(c);
request.setAttribute("styles", result);
RequestDispatcher view = request.getRequestDispatcher("results.jsp");
view.forward(request, response);
}
}
最后的JSP。
results.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<%@page import="java.util.*" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<h1 align="center">Beer Recommendations in JSP!!!</h1>
<%
List styles = (List)request.getParameter("styles");
Iterator it = styles.iterator();
while(it.hasNext()){
out.print("<br> try " + it.hasNext());
}
%>
</body>
</html>
感谢
“请求”的类型是什么? –
你想要将一个字符串转换为基于...什么,到底是什么?你想要一个字符串中所有字符的列表吗?你想分割特定分隔符上的字符串吗?或者你只是想将字符串插入列表中? –
或者'request.getParameter(..)'返回'Object',在这种情况下,已知'styles'将产生一个List类型的对象......没有更多的信息就无法分辨出来。 –