1、struts2流程: jsp页面-->web.xml-->struts.xml-->user.acrion-->UserAction.java 中的execute()--result

所以struts2中默认调用execute()方法。

2、Action中也可以自定义方法,只要在action的method属性选择,就可以利用该方法替换execute方法的作用。

struts.xml:

<action name="login" class="com.shensiyuan.struts.action.LoginAction" method="MyExecute">
<result name="success">/result.jsp</result>
</action>

LoginAction.java:

    @Override
public String execute(){
return "success";
}
public String MyExecute(){
System.out.println("MyExecute invoke!!!");
return SUCCESS;
}

aaarticlea/png;base64,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" alt="" />

注意:在开发中不推荐在Action中自定义多个方法,多个模块使用同一个Action,因为容易造成代码混乱,影响阅读和修改!

struts2内Action方法调用的更多相关文章

  1. Action方法调用

    一.Action访问路径 Action的访问路径是由struts.xml文件中配置的Action所在包的命名空间,Action的名字和常struts.action.extension共同决定的 例如: ...

  2. 第三篇——Struts2的动态方法调用

    Struts2动态方法调用 默认方式:默认执行方法中的execute方法,若指定类中没有该方法,默认返回success: method方式:执行method属性中定义的方法,没有该方法,页面报错: 通 ...

  3. struts2的动态方法调用(DMI)和通配符映射

    动态方法调用   1.Struts2默认关闭DMI功能,需要使用需要手动打开,配置常量 struts.enable.DynamicMethodInvocation = true 2.使用“!”方法,即 ...

  4. struts2的action方法匹配以及通配符的使用

    1. ActionMethod:Action执行的时候并不一定要执行execute方法,可以在配置文件中配置action的时候用"method"属性来指定执行哪个方法,也可以在ur ...

  5. struts2之动态方法调用(转)

    转自:http://blog.csdn.net/longwentao/article/details/6940289 当我们访问一个Action时,默认是访问execute()方法,但当在一个Acti ...

  6. Struts2之动态方法调用

    1.感叹号 前台页面 <%@ page language="java" contentType="text/html; charset=UTF-8" pa ...

  7. ssh整合思想 Spring与Hibernate和Struts2的action整合 调用action添加数据库 使用HibernateTemplate的save(entity)方法 update delete get 等方法crud操作

    UserAction类代码: package com.swift.action; import com.opensymphony.xwork2.ActionSupport; import com.sw ...

  8. Struts2之action 之 感叹号 ! 动态方法调用

    struts2的动态方法调用的方式: 1.第一种方式:设置method属性 在Action类中定义一个签名与execute方法相同.只是名字不同的方法,如定义为: public String logi ...

  9. Struts2中动态方法的调用

    Struts2中动态方法调用就是为了解决一个action对应多个请求的处理,以免action太多. 主要有一下三种方法:指定method属性.感叹号方式和通配符方式.推荐使用第三种方式. 1.指定me ...

随机推荐

  1. Sqlerver_各类函数

    SQL Aggregate 函数 SQL Aggregate 函数计算从列中取得的值,返回一个单一的值. 有用的 Aggregate 函数: AVG() - 返回平均值-SELECT AVG(colu ...

  2. windows下重新安装TCP/IP协议栈

    一.windows重装TCP/IP协议     前两天在windows下安装开发环境的时候,把系统的TCP/IP协议栈给搞跪了,导致系统无法ping localhost.无法在程序中创建socket等 ...

  3. iOS开发 判断用户是否开启了定位

    - (BOOL)achiveUserLocationStart { CLAuthorizationStatus status = [CLLocationManager authorizationSta ...

  4. SqlServer扩展存储过程

    1. 扩展存储过程xp_cmdshell用法: --1.启用 SP_CONFIGURE RECONFIGURE GO SP_CONFIGURE RECONFIGURE GO --2.用法 master ...

  5. php 注入

    SELECT * FROM `users` WHERE name = 'a\'b\'d' LIMIT 0 , 30 这个是有结果的,运行正确的,和一般想的不一样,单引号里面可以套单引号,只要里面的单引 ...

  6. C++ Primer 笔记(2)第二章 变量与基本类型

    第二章 变量与基本类型 1.基本内置类型包括算术类型和空类型,算术类型分为两类:整型(包括字符和布尔类型)和浮点型: 2.布尔类型(bool)的取值是真(true)或者假(false): 3.字面值常 ...

  7. R语言实战

    教材目录 第一部分 入门 第一章 R语言介绍 第二章 创建数据集 第三章 图形初阶 第四章 基本数据管理 第五章 高级数据管理 第二部分 基本方法 第六章 基本图形 第七章 基本统计方法 第三部分 中 ...

  8. 按键精灵 句柄 获得句柄 控制windows窗口 后台

    新建一个文本文档,打开,Windows就会给这个文本文档的窗口临时分配唯一的一串数字来标识这个窗体,以区别于其他窗口,这串数字就叫句柄.   因为句柄是临时随机分配的,所以每次虽然是打开同一个文件,但 ...

  9. jmeter笔记7

    一.脚本录制(Jmeter): Jmeter 脚本(.jmx)为 xml 格式,树形结构,由元件组成,使用“取样器”产生请求. 在“工作台”添加“HTTP 代理服务器” 端口: 代理服务器的端口,默认 ...

  10. [BI基础] 一些不得不了解的概念

    0.Hadoop hadoop主要是用来对海量数据进行存储和计算的. 它本身是一个分布式系统,核心由分布式文件系统hdfs,和分布式计算框架mapreduce组成,在存储和计算时能够发挥出集群中每台机 ...