JSP Servlet参考

最新推荐文章于 2024-06-06 20:20:02 发布

原创最新推荐文章于 2024-06-06 20:20:02 发布 · 915 阅读

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CC 4.0 BY-SA版权

文章标签：

#jsp #servlet #import #integer #include #exception

本文介绍了JSP和Servlet的基本用法，包括JSP的声明、注释、使用javabean、页面跳转以及Servlet的doGet方法。还涵盖了错误处理、包含页面、参数传递等内容，并展示了JDBC驱动操作的例子和HTTP请求的相关属性。

---------------------------------------
JSP Example
---------------------------------------
<%@ page contentType="text/html; charset=gb2312"%>
<%@ page errorPage="errorPage.jsp" %>
<%@ page import="java.util.*"%>
<%! String s = "hello" %>
<%=s%>

---------------------------------------
SERVLET Example
---------------------------------------
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class HelloWorld extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException
{
    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    out.println("hello world");
}
}

---------------------------------------
参考
---------------------------------------
定义编码
<%@ page contentType="text/html; charset=gb2312"%>

import
<%@ page import="java.util.*, java.net.*" %>

错误处理页面
<%@ page errorPage="errorPage.jsp" %>

使用taglib
<%@ taglib uri=" http://www.jspcentral.com/tags " prefix="ofbiz" %> or
<%@ taglib uri="ofbizTags" prefix="ofbiz" %>
<ofbiz:loop>
.
.
</ofbiz:loop>

声明，注释
<%! int i = 0; %>
<%! void myMethod() {} %>

使用javabean
<jsp:useBean id="myBean" type="vic.test.TestBean" scope="request" />
<%=myBean.getAge()%>

注释

<%-- 注释 --%>

包含页面
<%@ include file="包含的文件" %>

<jsp:include page="aa.jsp | <%=incFileName%>" flush="true"/>

<jsp:include page="aa.jsp | <%=incFileName%>" flush="true">
    <jsp:param name="age" value="30 | <%=myAge%>"/>
</jsp:include>

页面跳转
<jsp:forward page="iWantToGo.jsp" />

<jsp:forward page="iWantToGo.jsp">
    <jsp:param name="age" value="30/>
</jsp:forward>

response.sendRedirect("iWantToGo.jsp");

内部对象
request 　　客户端请求
response　　网页传回客户端的响应
　　session 　　与请求有关的会话
　　pageContext 网页的属性是在这里管理
　　application servlet正在执行的内容
　　out 　　　　用来传送响应的输出流
　　config　　　servlet的架构对象
　page　　　　 JSP网页本身
　　exception　　针对错误网页，未捕捉的例外

---------------------------------------
JDBC Driver 操作例子
---------------------------------------


<%@ page info="database handler"%>
<%@ page import="java.io.*"%>
<%@ page import="java.util.*"%>
<%@ page import="java.sql.*"%>
<%@ page import="javax.servlet.*"%>
<%@ page import="javax.servlet.http.*"%>

<%
try {
    //加载驱动程序
    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
    String url="jdbc:odbc:test";
    //"test"是系统dsn名
    Connection con=DriverManager.getConnection(url, "administrator", "password");
    //"administrator","password"是用户名和口令
    //然后创建一个JDBC声明
    Statement stmt = con.createStatement();
    String query="CREATE TABLE COFFEES" +
        "(COF_NAME VARCHAR(32),"+
        "SUP_ID INTEGER,"+
        "PRICE FLOAT,"+
        "SALES INTEGER,"+
        "TOTAL INTEGER)";
        //执行声明
        stmt.executeUpdate(query);
} catch (Exception e) {

}
//输出确认信息
out.println("table coffees created");
%>

Page
<%@ page
[ language="java" ]
[ extends="package.class" ]
[ import="{package.class | package.*}, ..." ]
[ session="true | false" ]
[ buffer="none | 8kb | sizekb" ]
[ autoFlush="true | false" ]
[ isThreadSafe="true | false" ]
[ info="text" ]
[ errorPage="relativeURL" ]
[ contentType="mimeType [ ;charset=characterSet ]" | "text/html ; charset=ISO-8859-1" ]
[ isErrorPage="true | false" ]
%>

REQUEST
---------------------------------------------------
request.getAttribute("xxAtt"); // Object
request.setAttribute("xxAtt", "xxVal"); // void
request.getParameter("xxParam"); // String
request.getParameterNames(); // Enumeration
request.getParameterValues("xxParam"); //String[]
request.getRequestDispatcher("iWantTo.jsp").forward(request, response);

http://localhost:8080/vps/control/testList
request.getRemoteAddr() 127.0.0.1
request.getMethod() GET
request.getRequestURI() /vps/control/testList
request.getProtocol() HTTP/1.1
request.getPathInfo() /testList

SESSION
---------------------------------------------------
session.getCreationTime() // long
session.getLastAccessedTime() // long
session.getId() // String