Java Web javaBean

javaBean的编写:

   标准的java类;

     需要定义一个无参的构造方法;

   定义有属性;

   定义有属性的getter和setter方法;

   实现serializable接口;

ussBean动作:

  使用userBean动作的代码;

<jsp:useBean class="webbook.chapter9.Book" id="book" scope="page"/>

  等价的代码:

<%

  webbook.chapter9.Book book=null;

  if(pageContext.getAttribute("book")==null){

  book=new Book();

  pageContext.setAttribute("book",book);

    }

}else{

book=(Book)pageContext.getAttribute("book");

}

%>

setProperty动作:

  使用setProperty动作的代码;

  <jsp:setProperty name="book" property="name" value="Hibernate"/>

  等价代码;

  <%book.setName("Hibernate");%>

getProperty动作:

  使用getProperty动作的代码;

  <jsp:getProperty name="book" name="name"/>

  等价代码:

  <%= book.getName() %>

测试代码:

book.html

代码:

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
 <head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  <title>Insert title here</title>
 </head>
 <body>
<form name="form1" method="post" action="displayBook.jsp">
ISBN:<input type="text" name="isbn"> <br>   
书名:<input type="text" name="name"> <br>   
作者:<input type="text" name="author"> <br>   
是否售出:是<input type="radio" name="sale" value="true" checked>
    否<input type="radio" name="sale" value="false"><br>   
<input type="submit" value="提交">    
<input type="reset" value="重来">
</form>
</body>
</html>

Book.java

代码:

package webbook.chapter9;

public class Book {
 private String isbn;
 private String name;
 private String author;
 private boolean sale;

 public String getIsbn() {
  return isbn;
 }

 public void setIsbn(String isbn) {
  this.isbn = isbn;
 }

 public String getName() {
  return name;
 }

 public void setName(String name) {
  this.name = name;
 }

 public String getAuthor() {
  return author;
 }

 public void setAuthor(String author) {
  this.author = author;
 }

 public boolean isSale() {
  return sale;
 }

 public void setSale(boolean sale) {
  this.sale = sale;
 }
}

displayBook.jsp

代码:

<%@ page language="java" contentType="text/html; charset=UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <title>display Book Bean information</title>   
</head> 
 <body>
<% request.setCharacterEncoding("utf-8");%> 
<jsp:useBean class="webbook.chapter9.Book" id="book" scope="request"/>  
<jsp:setProperty name="book" property="*"/>
ISBN:<jsp:getProperty name="book" property="isbn"/><br>
书名:<jsp:getProperty name="book" property="name"/><br>
作者:<% out.println(book.getAuthor()); %><br><br>
是否售出:
<%
if(book.isSale()){
 out.println("是");
}else{
 out.println("否");
}
%>
<br>  
</body>
</html>

  

原文地址:https://www.cnblogs.com/hongten/p/2114782.html