Spring根据XML配置文件注入属性的方法
方法一使用setter方法
package com.swift; public class Book { private String bookName; public void setBook(String bookName) { this.bookName = bookName; } @Override public String toString() { return "Book [book=" + bookName + "]"; } }
在Spring框架中,假定Servlet类中不能直接生成Book类的对象,并注入String bookName的属性值
而需要通过配置文件xml的方法
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <!-- IoC 控制反转 SpringSpring根据XML配置文件注入属性 --> <bean id="book" class="com.swift.Book"> <property name="bookName" value="三体——黑暗森林"></property> </bean> </beans>
Servlet类代码:
package com.swift; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; @WebServlet("/book") public class BookServlet extends HttpServlet { private static final long serialVersionUID = 1L; public BookServlet() { super(); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setCharacterEncoding("utf-8"); response.setContentType("text/html;charset=utf-8"); response.getWriter().append("Served at: ").append(request.getContextPath()); @SuppressWarnings("resource") //就是下边这几句了 ApplicationContext context=new ClassPathXmlApplicationContext("a.xml"); Book book=(Book) context.getBean("book"); String bookInfo=book.fun(); response.getWriter().println(); response.getWriter().append(bookInfo); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }
注意
beans 、context、core 和expression核心jar包
以及commons-logging 和log4j两个jar包不要缺少
方法二使用有参构造方法
以上这篇Spring根据XML配置文件注入属性的方法就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持我们。
赞 (0)