JavaWeb学习笔记1——第一个简单的JavaWeb项目

首先打开MyEclipse，并在菜单上选择File—New—Other，在弹出的对话框中选择Web Project，然后Next，随后在弹出的对话框中填写Project Name：firstWeb，到此已经建立好了一个JavaWeb项目，名为firstWeb。

然后需要在该项目下新建一个Servlet。方法如下，选择File—New—Other，在弹出额度对话框中找到Web下面的Servlet，单击Next，在弹出的对话框中输入package名称：com.test.secondWeb（也可以根据自己习惯改为别的名称），Servlet名称：HelloServlet，然后Finish。

到这里准备工作已经完成，下面是刺激的代码环节。

MyEclipse自动生成的HelloServlet.java只是完成了一局简单话的输出，这里我们需要自己进行修改源代码。

 

package com.test.secondWeb;

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 HelloServlet extends HttpServlet {

	/**
		 * Constructor of the object.
		 */
	public HelloServlet() {
		super();
	}

	/**
		 * Destruction of the servlet. 

		 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
		 * The doGet method of the servlet. 

		 *
		 * This method is called when a form has its tag value method equals to get.
		 * 
		 * @param request the request send by the client to the server
		 * @param response the response send by the server to the client
		 * @throws ServletException if an error occurred
		 * @throws IOException if an error occurred
		 */
	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

		response.setCharacterEncoding("UTF-8");
		request.setCharacterEncoding("UTF-8");
		
		response.setContentType("text/html");
		PrintWriter out = response.getWriter();
		out.println("");
		out.println("");
		out.println("");
		out.println("");
		out.println("  ");
		
		String requestURI=request.getRequestURI();
		out.print("
");
		out.print("请输入您的名字:");
		out.println("");
		out.println("
");
		out.println("");
		
		String name =request.getParameter("name");
		if(name!=null&&name.trim().length()>0){
			
			out.println("您好,"+name+".欢迎来到Java Web世界.");
			
		}
		out.println("  ");
		out.println("");
		out.flush();
		out.close();
	}

	/**
		 * The doPost method of the servlet. 

		 *
		 * This method is called when a form has its tag value method equals to post.
		 * 
		 * @param request the request send by the client to the server
		 * @param response the response send by the server to the client
		 * @throws ServletException if an error occurred
		 * @throws IOException if an error occurred
		 */
	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

		this.doGet(request, response);
		
		
	}

	/**
		 * Initialization of the servlet. 

		 *
		 * @throws ServletException if an error occurs
		 */
	public void init() throws ServletException {
		// Put your code here
	}

}

代码完成，想要看到项目运行效果还需要进行吧项目部署到Tomcat上，MyEclipse2017部署方法（如果其他版本略有不同请自行找度娘吧）：菜单上选择windows—show view—Servers，这是MyEclipse下方位置会弹出Servers框，在你自己安装的Tomcat上（）右键选择Add/Remove Deployments···，然后选择项目firstWeb，点击add，完成关闭对话框。

 

然后就是看看项目效果了，首先启Tomcat，方法是在刚才你自己安装的Tomcat上右键选择Strat，然后等待一会儿（这时代码框下面会有一些文字不断刷新，等到一切回归风平浪静就ok了，大概也就5、6秒钟，具体看电脑配置和项目大小吧）。

然后打开MyEclipse自带的浏览器，如图：

然后在地址框中输入：http://localhost:8080/firstWeb/servlet/HelloServlet  回车即可看到效果图

可以在文本框中输入你的名字，点击“提交查询内容”，最后效果如图：