package com.jspservletcookbook;
import java.io.IOException;
import java.io.PrintWriter;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.*;
import javax.servlet.http.*;
public class BeanServlet extends HttpServlet {
private StockPriceBean spbean;
public void init() throws ServletException {
Context env = null;
try{
env = (Context) new InitialContext().lookup("java:comp/env");
spbean = (StockPriceBean) env.lookup("bean/pricebean");
//close the InitialContext
env.close();
if (spbean == null)
throw new ServletException("bean/pricebean is an unknown JNDI object");
} catch (NamingException ne) {
try{ env.close();} catch (NamingException nex) { }
throw new ServletException(ne);
}
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
//set the MIME type of the response, "text/html"
response.setContentType("text/html");
//use a PrintWriter send text data to the client who has requested the servlet
java.io.PrintWriter out = response.getWriter();
//Begin assembling the HTML content
out.println("<html><head>");
out.println("<title>Stock Price Fetcher</title></head><body>");
out.println("<h2>Please submit a valid stock symbol</h2>");
//make sure method="post" so that the servlet service method
//calls doPost in the response to this form submit
out.println(
"<form method=\"post\" action =\"" + request.getContextPath() +
"/namingbean\" >");
out.println("<table border=\"0\"><tr><td valign=\"top\">");
out.println("Stock symbol: </td> <td valign=\"top\">");
out.println("<input type=\"text\" name=\"symbol\" size=\"10\">");
out.println("</td></tr><tr><td valign=\"top\">");
out.println("<input type=\"submit\" value=\"Submit Info\"></td></tr>");
out.println("</table></form>");
out.println("</body></html>");
out.close();
} //end doGet
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws java.io.IOException{
String symbol;//this will hold the stock symbol
float price = 0f;
symbol = request.getParameter("symbol");
boolean isValid = (symbol == null || symbol.length() < 1) ? false : true;
//set the MIME type of the response, "text/html"
response.setContentType("text/html");
//use a PrintWriter send text data to the client who has requested the servlet
java.io.PrintWriter out = response.getWriter();
//Begin assembling the HTML content
out.println("<html><head>");
out.println("<title>Latest stock value</title></head><body>");
if ((! isValid) || spbean == null){
out.println("<h2>Sorry, the stock symbol parameter was either empty or null</h2>");
} else {
out.println("<h2>Here is the latest value of "+ symbol +"</h2>");
spbean.setSymbol(symbol);
price = spbean.getLatestPrice();
out.println( (price < 1 ? "The symbol is probably invalid." : ""+price) );
}
out.println("</body></html>");
}// doPost
}//BeanServlet
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