JavaWeb的第一个程序（HelloWorld!）

JavaWeb的第⼀个程序（HelloWorld!）# JJU_⼲⼲
Tomcat配置
1. 下载：
2. 打开eclipse，在windows选项 / Server / Runtime Environment / Add ，添加下载后解压好的的Tomcat⽂件夹
⽅法⼀：.java + .xml
1. 创建⼀个Java Web 项⽬
（1）选中 project:
（2）创建动态web项⽬：
（3）点击next，命名项⽬名；再连续点击next，勾选⽣成xml⽂件选项
--------------------------------------------------------------------------------------------------------
2. 代码：java+xml
.java：
package case_01;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class HelloWorld extends HttpServlet{
public void service(HttpServletRequest req, HttpServletResponse res) throws
IOException,ServletException{
PrintWriter out = res.getWriter();
out.print("Hellow World!");
}
}
.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="/2001/XMLSchema-instance" xmlns="/xml/ns/javaee" xsi:schemaLocation="/xml/ns/javaee /xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" <display-name>Servlet_01</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>hello</servlet-name>
<!--包名.类名-->
<servlet-class>case_01.HelloWorld</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>hello</servlet-name><!--这⾥的servlet-name⼀定要和上⾯的⼀样-->
<url-pattern>/hello</url-pattern><!-- 这⾥⼀定要加左斜杠，且这⾥的名字可以任意，不是⾮得是hello，但习惯保持⼀样 -->
</servlet-mapping>
</web-app>
xml位置：
-------------------------------------------------------------------------------------
3. 运⾏：
在 .java中⿏标右键，选择Run as 中的 Run on Server
选择Tomcat容器，点击finish
4. 运⾏结果：
⽅法⼆：使⽤注解⽅式配置Sevrlet：直接创建⼀个servlet项⽬，⾃动⽣成⼀个模板
代码：
package case_01;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class HelloWorld_02
*/
@WebServlet("/HelloWorld_02")
public class HelloWorld_02 extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public HelloWorld_02() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub
// 以下两条语句防⽌输⼊中⽂出现乱码
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset = utf-8");
response.getWriter().append("Served at: ").append(request.getContextPath());
PrintWriter out = response.getWriter();
out.print("Hellow World! I'm ⼲⼲");
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub
doGet(request, response);
}
}
运⾏结果：。