/*
作者:何志强[hhzqq@21cn.com]
日期:2000-08-10
版本:1.0
功能:servlet基础例程 – helloservlet
*/
import java.io.*;
import java.text.*; //messageformat
import javax.servlet.*;
import javax.servlet.http.*;
public class helloservlet extends httpservlet{
//页面标题
protected static final string strtitle = "servlet基础例程 – helloservlet";
//页眉
protected static final string strheader =
"<html>"+
"<head>"+
"<meta http-equiv=\"content-type\" content=\"text/html; charset=gb2312\">"+
"<title>{0}</title>"+
"</head>"+
"<body>";
//页脚
protected static final string strfooter =
"</body>"+
"</html>";
//表单
protected static final string strform =
"<form action=\"{0}\" method=\"post\">"+
"您尊姓大名:<input type=\"text\" name=\"name\">"+
"<input type=\"submit\" name=\"submit\" value=\"提交\">"+
"</form>";
protected static final string strhello =
"您好,{0},欢迎来到servlet/jsp世界!";
//出错信息
protected static final string strerror =
"<h2><font color=\"#ff0000\">{0}</font></h2>";
protected void doget(httpservletrequest req,httpservletresponse resp) throws servletexception,ioexception{
process(req,resp);
}
protected void dopost(httpservletrequest req,httpservletresponse resp) throws servletexception,ioexception{
process(req,resp);
}
protected void process(httpservletrequest req,httpservletresponse resp) throws servletexception,ioexception{
try{
string submit = req.getparameter("submit");
if(submit==null)
printform(req,resp);
else
printhello(req,resp);
}
catch(exception e){
printerror(e.tostring(),req,resp);
}
}
protected void printform(httpservletrequest req,httpservletresponse resp) throws servletexception,ioexception{
//在使用printwriter前得先设置content type
resp.setcontenttype("text/html");
printwriter out = resp.getwriter();
//输出页眉
out.print(messageformat.format(strheader,new object[]{strtitle+" – 请输入尊姓大名"}));
//输出表单
out.print(messageformat.format(strform,new object[]{req.getcontextpath()+req.getservletpath()}));
//输出页脚
out.print(strfooter);
out.flush();
}
protected void printhello(httpservletrequest req,httpservletresponse resp) throws servletexception,ioexception{
//获取用户输入的数据
string name = req.getparameter("name");
if(name==null)
name = "无名氏";
//在使用printwriter前得先设置content type
resp.setcontenttype("text/html");
printwriter out = resp.getwriter();
//输出页眉
out.print(messageformat.format(strheader,new object[]{strtitle+" – 欢迎您"}));
//输出欢迎信息
out.print(messageformat.format(strhello,new object[]{name}));
//输出页脚
out.print(strfooter);
out.flush();
}
protected void printerror(string error, httpservletrequest req,httpservletresponse resp) throws servletexception,ioexception{
//在使用printwriter前得先设置content type
resp.setcontenttype("text/html");
printwriter out = resp.getwriter();
//输出页眉
out.print(messageformat.format(strheader,new object[]{strtitle+" – 出错信息"}));
//输出出错信息
out.print(messageformat.format(strerror,new object[]{error}));
//输出页脚
out.print(strfooter);
out.flush();
}
}
