?? 入門 15 - 使用dispatchaction類別 - javaworld@tw.htm
字號(hào):
?<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<!-- saved from url=(0071)http://www.javaworld.com.tw/confluence/pages/viewpage.action?pageId=607 -->
<HTML><HEAD><TITLE>入門 15 - 使用DispatchAction類別 - JAVAWORLD@TW</TITLE>
<META http-equiv=Content-Type content="text/html; charset=utf-8"><!-- CONFL-BEGIN standardHeader -->
<META http-equiv=Pragma content=no-cache>
<META http-equiv=Expires content=-1>
<SCRIPT language=javascript> var contextPath = '/confluence';</SCRIPT>
<LINK href="入門 15 - 使用DispatchAction類別 - JAVAWORLD@TW.files/main-action.css"
type=text/css rel=stylesheet><LINK href="/confluence/images/icons/favicon.ico"
rel="shortcut icon"><LINK href="/confluence/images/icons/favicon.png"
type=image/png rel=icon>
<SCRIPT
src="入門 15 - 使用DispatchAction類別 - JAVAWORLD@TW.files/effects.js"></SCRIPT>
<!-- CONF-END standardHeader -->
<META content="MSHTML 6.00.2800.1491" name=GENERATOR></HEAD>
<BODY onload=placeFocus()>
<DIV id=Content>
<TABLE cellSpacing=0 cellPadding=0 width="100%" border=0>
<TBODY>
<TR>
<TD class=logocell width="60%" rowSpan=2>
<DIV class=spacenametitle><A
href="http://www.javaworld.com.tw/confluence/display/opensrc"><IMG
src="入門 15 - 使用DispatchAction類別 - JAVAWORLD@TW.files/confluence_logo.gif"
align=bottom border=0></A> <A
href="http://www.javaworld.com.tw/confluence/display/opensrc">OpenSource
Project</A></DIV></TD>
<TD vAlign=top align=right width="40%">
<TABLE cellSpacing=1 cellPadding=2 align=right bgColor=#ffffff border=0>
<TBODY>
<TR>
<TD class=navItem onmouseover="this.className='navItemOver'"
onclick="window.document.location='/confluence/'"
onmouseout="this.className='navItem'" vAlign=center noWrap
align=middle> <A title="Go to the Confluence Dashboard"
accessKey=h onclick="return false"
href="http://www.javaworld.com.tw/confluence/"><U>H</U>OME</A>
</TD>
<TD class=navItem onmouseover="this.className='navItemOver'"
onclick="window.document.location='/confluence/spaces/listspaces.action'"
onmouseout="this.className='navItem'" vAlign=center noWrap
align=middle> <A title="The spaces available for you"
accessKey=s onclick="return false"
href="http://www.javaworld.com.tw/confluence/spaces/listspaces.action"><U>S</U>PACES</A>
</TD></TR></TBODY></TABLE></TD></TR>
<TR>
<TD vAlign=bottom align=right><SPAN class=smalltext><A
href="http://www.javaworld.com.tw/confluence/login.action?os_destination=/pages/viewpage.action?pageId=607">Log
In</A> </SPAN><A
href="http://www.javaworld.com.tw/confluence/pages/viewpage.action?pageId=607&decorator=printable"><IMG
title="View a printable version of the current page." height=16
alt="View a printable version of the current page." hspace=1
src="入門 15 - 使用DispatchAction類別 - JAVAWORLD@TW.files/print_16.gif"
width=16 align=absMiddle vspace=1 border=0></A> <A
href="http://confluence.atlassian.com/display/DOC"><IMG
title="Get help from the Confluence website." height=16
alt="Get help from the Confluence website." hspace=1
src="入門 15 - 使用DispatchAction類別 - JAVAWORLD@TW.files/help_16.gif" width=16
align=absMiddle vspace=1 border=0></A> </TD></TR></TBODY></TABLE><!-- CONF-BEGIN breadcrumbsAndSearch -->
<DIV class=breadcrumbs width="100%">
<TABLE cellSpacing=0 cellPadding=0 width="100%" border=0>
<TBODY>
<TR>
<TD> Location: <A
href="http://www.javaworld.com.tw/confluence/dashboard.action">Dashboard</A>
> <A
href="http://www.javaworld.com.tw/confluence/spaces/viewspacesummary.action?key=opensrc">opensrc</A>
> <A
href="http://www.javaworld.com.tw/confluence/pages/listpages.action?key=opensrc">Pages</A>
> <A
href="http://www.javaworld.com.tw/confluence/display/opensrc/Home">Home</A>
> <A
href="http://www.javaworld.com.tw/confluence/display/opensrc/Struts">Struts</A>
> <A
href="http://www.javaworld.com.tw/confluence/pages/viewpage.action?pageId=1958">Struts入門</A>
> <A
href="http://www.javaworld.com.tw/confluence/pages/viewpage.action?pageId=607">入門
15 - 使用DispatchAction類別</A> </TD>
<FORM name=searchForm action=/confluence/dosearchsite.action
method=get><INPUT type=hidden value=true name=quickSearch>
<TD vAlign=bottom align=right width=200><A style="TEXT-DECORATION: none"
href="http://www.javaworld.com.tw/confluence/searchsite.action"><U>Q</U>uick
<U>Search</U></A>:<INPUT accessKey=q size=10 name=searchQuery.queryString><INPUT type=submit value=Go><BR><IMG height=1
src="入門 15 - 使用DispatchAction類別 - JAVAWORLD@TW.files/spacer.gif"
width=200></TD></FORM></TR></TBODY></TABLE></DIV><!-- CONF-END breadcrumbsAndSearch -->
<TABLE cellSpacing=0 cellPadding=5 width="100%" border=0>
<TBODY>
<TR>
<TD>
<TABLE cellSpacing=0 cellPadding=0 width="100%" border=0>
<TBODY>
<TR>
<TD class=pagebody vAlign=top>
<DIV class=pageheader><SPAN class=pagetitle>入門 15 -
使用DispatchAction類別</SPAN> </DIV>
<SCRIPT language=javascript> function toggle(id) { var oldAttachmentVersionsBlock = document.getElementById('attachment' + id); with (oldAttachmentVersionsBlock.style) { if ( display == "none" ) display = "" else display = "none" } var arrowIcon = document.getElementById('arrow' + id); with (arrowIcon) { if (src != null && (src.indexOf('/confluence/images/icons/arrow_closed_active_16.gif') != -1 || src.indexOf('/confluence/images/icons/arrow_closing_active_16.gif') != -1)) { src = '/confluence/images/icons/arrow_opening_active_16.gif'; } else { src = '/confluence/images/icons/arrow_closing_active_16.gif'; } } } </SCRIPT>
<DIV class=pagesubheading>Last changed on Oct 27, 2004 by <A
href="http://www.javaworld.com.tw/confluence/display/~koji">koji
lin</A>
</DIV><!-- page content --> 在之前的主題中，您為每一個(gè)動(dòng)作撰寫一個(gè)Action類，隨著網(wǎng)站的增大，維護(hù)Action的成本也就隨著增大，您可以使用模組化來管理，而另一方面，在檢視一些Action時(shí)，您會(huì)發(fā)現(xiàn)某些Action所執(zhí)行的，其實(shí)是完成一個(gè)業(yè)務(wù)邏輯所需要的連續(xù)動(dòng)作或相關(guān)動(dòng)作，例如帳號(hào)的登入、登出等動(dòng)作。<BR> 在Struts中，您可以使用org.apache.struts.actions.DispatchAction類別將完成一個(gè)業(yè)務(wù)邏輯所需要的連續(xù)動(dòng)作或相關(guān)動(dòng)作集中於一個(gè)Action類中，在繼承DispatchAction後，您不再是重新定義execute()方法，而是撰寫自己的動(dòng)作，execute()方法是在DispatchAction抽象類定義
的。<BR> 例如我們可以繼承DispatchAction來定義一個(gè)AccountAction，在當(dāng)中集中管理一些與帳號(hào)相關(guān)的操作，一個(gè)例子如下：
<DIV class=code
style="BORDER-TOP-STYLE: solid; BORDER-RIGHT-STYLE: solid; BORDER-LEFT-STYLE: solid; BORDER-BOTTOM-STYLE: solid">
<DIV class=codeHeader
style="BORDER-BOTTOM-STYLE: solid"><B>AccountAction.java</B></DIV>
<DIV class=codeContent><PRE><SPAN class=java-keyword>package</SPAN> onlyfun.caterpillar;
<SPAN class=java-keyword>import</SPAN> javax.servlet.http.*;
<SPAN class=java-keyword>import</SPAN> org.apache.struts.action.*;
<SPAN class=java-keyword>import</SPAN> org.apache.struts.actions.*;
<SPAN class=java-keyword>public</SPAN> class AccountAction <SPAN class=java-keyword>extends</SPAN> DispatchAction {
<SPAN class=java-keyword>public</SPAN> ActionForward login(ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
<SPAN class=java-keyword>throws</SPAN> Exception {
<SPAN class=java-comment>// 進(jìn)行一些Login的邏輯</SPAN>
......
}
<SPAN class=java-keyword>public</SPAN> ActionForward logout(ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
<SPAN class=java-keyword>throws</SPAN> Exception {
<SPAN class=java-comment>// 進(jìn)行一些Logout的邏輯</SPAN>
?? 快捷鍵說明
復(fù)制代碼
Ctrl + C
搜索代碼
Ctrl + F
全屏模式
F11
切換主題
Ctrl + Shift + D
顯示快捷鍵
?
增大字號(hào)
Ctrl + =
減小字號(hào)
Ctrl + -