struts2 实现文件下载

页面采用ajax方式判断文件是否存在并下载：

$.ajax({

url:'${pageContext.request.contextPath}'+downloadWPath, //此处给出文件地址，如果找不到，会走下面的error处理！

success:function(){

location.href='downloadKeyWord?keywordpath='+encodeURIComponent(downloadWPath);

},

error:function(){

$.messager.show({

title: '提示',

msg: "该关键字文件已不存在!",

showtype:'fade',

timeout:3000,

style:{

right:'',

bottom:''

}

});

}

});

strrut.xml 配置中，把下载操作放在ajax的处理包中，

<package name="ajax" extends="json-default">

<action name="downloadKeyWord" class="com.geo.dsp.ioperator.action.ManageExecuteAction" method="downloadKeyWord">

<result name="success" type="stream">

<param name="contentType">application/octet-stream;charset=ISO8859-1</param>

<param name="inputName">keyWordStream</param>

<param name="contentDisposition">filename=${downloadFileName}</param>

<param name="bufferSize">1024</param>

</result>

</action>

<package>

java方法：

public String downloadKeyWord() {

String keyWordpath = request.getParameter("keywordpath");

keyWordStream = ServletActionContext.getServletContext().getResourceAsStream(keyWordpath);

downloadFileName = keyWordpath.split("/")[keyWordpath.split("/").length - 1].split("_")[0] + ".txt"; //下载时显示文件的名字

return "success";

}