jsp/servlet入门 - 爱码网

tomcat发布目录设置

编辑tomcat/conf/server.xml

在<Host>和</Host>间添加如下：<Context path="/myapp" docBase="d:/myapp" debug="0" reloadable="true"></Context>

启动tomcat后即可访问：http://localhost:8080/myapp

web应用目录结构

d:/myapp/*.jsp

d:/myapp/WEB-INF/web.xml

d:/myapp/WEB-INF/classes/ 保存*.class文件

d:/myapp/WEB-INF/lib/ 保存*.jar文件

jsp基础知识

原理：jsp由系统编译成servlet，servlet负责相应用户请求。

注释：<%--注释--%>

声明：<%!声明变量和函数%>

输出表达式：<%=输出表达式%>

连接数据库jsp实例：test.jsp

<%@ page import="java.sql.*"%>
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<!DOCTYPE html>
<html>
<head>
<title>连接数据库脚本测试</title>
</head>
<body>
<table bgcolor="yellow" border="1" width="300px">
    <%
        Class.forName("com.mysql.jdbc.Driver");
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "123456");
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("select * from user");
        while (rs.next()) {
    %>
    <tr>
        <td><%=rs.getString(1)%></td>
        <td><%=rs.getString(2)%></td>
        <td><%=rs.getString(3)%></td>
    </tr>
    <%
        }
    %>
</table>
</body>
</html>

编译指令：page、include、taglib <%@ 编译指令名属性名="属性值"... %>

动作指令：jsp:forward/jsp:param/jsp:include/jsp:plugin/jsp:useBean/jsp:setProperty/jsp:getProperty

package com.zzz.lcy;
public class Person {
    String name;
    int age;
    public Person() {
    }
    public Person(String name, int age) {
        this.name = name;
        this.age = age;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getName() {
        return name;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public int getAge() {
        return age;
    }
}

默认构造函数不能少，编译javac Person -d d:/myapp/WEB-INF/classes/

<%@page language="java" contentType="text/html; charset=utf-8"%>
<!DOCTYPE html>
<html>
<head>
<title>BeanTest</title>
</head>
<body>
<jsp:useBean id="beanTest1" class="com.zzz.lcy.Person" scope="page"></jsp:useBean>
<jsp:setProperty property="name" name="beanTest1" value="lcy" />
<jsp:setProperty property="age" name="beanTest1" value="34" />
<jsp:getProperty property="name" name="beanTest1" />
<jsp:getProperty property="age" name="beanTest1" />
</body>
</html>

内置对象：application/config/exception/out/pageContext/request/response/session

参考：http://www.cnblogs.com/jbelial/archive/2012/03/20/2396585.html

servlet配置

编辑d:/myapp/WEB-INF/web.xml

在<webapp></webapp>间添加如下：

<servlet>
    <servlet-name>hello</servlet-name>
   <servlet-class>zzz.lcy.servlet.HelloWorld</servlet-class>
</servlet>
<servlet-mapping>
   <servlet-name>hello</servlet-name>
   <url-pattern>/servlet/HelloWorldDemo</url-pattern>
</servlet-mapping>

注意：<servlet-name>必须对应上

访问网址：http://localhost:8080/myapp/servlet/HelloWorldDemo

package zzz.lcy.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class HelloWorld extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response) {
        response.setContentType("text/html;charset=utf-8");
        try {
            PrintWriter out = response.getWriter();
            out.println("hello, world.");
            out.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public void doPost(HttpServletRequest request, HttpServletResponse response) {
        doGet(request, response);
    }
}

jsp论坛实例（部分代码）

javabean

public class User {
    private int id;
    private String name;
    private String password;
    private String nickname;
    public User() {
    }
    public User(String name, String password, String nickname) {
        this.name = name;
        this.password = password;
        this.nickname = nickname;
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String getNickname() {
        return nickname;
    }
    public void setNickname(String nickname) {
        this.nickname = nickname;
    }
}

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