Struts基础学习-文件上传与下载

文件上传

简单文件上传

jsp页面

<s:form action="uploadPro" enctype="multipart/form-data">    <s:textfield name="title" label="文件标题" /><br/>    <s:file name="upload" label="选择文件" /><br />    <s:submit value="上传" /></s:form>

action文件

public class UploadAction extends ActionSupport{    private String title;    private File upload;    //上传文件类型    private String uploadContentType;    //上传文件名    private String uploadFileName;    //配置文件保存属性    private String savePath;public String getTitle() {return title;}public void setTitle(String title) {this.title = title;}public File getUpload() {return upload;}public void setUpload(File upload) {this.upload = upload;}public String getUploadContentType() {return uploadContentType;}public void setUploadContentType(String uploadContentType) {this.uploadContentType = uploadContentType;}public String getUploadFileName() {return uploadFileName;}public void setUploadFileName(String uploadFileName) {this.uploadFileName = uploadFileName;}public String getSavePath() {return ServletActionContext.getServletContext().getRealPath("/WEB-INF/"+savePath);}public void setSavePath(String savePath) {this.savePath = savePath;}public String execute() throws Exception{FileOutputStream fos=new FileOutputStream(getSavePath()+"\\"+getUploadFileName());FileInputStream fis=new FileInputStream(getUpload());byte[] buffer=new byte[1024];int len=0;while((len=fis.read(buffer))>0){fos.write(buffer,0,len);}return SUCCESS;}    }

配置文件

<action name="uploadPro" class="app.action.UploadAction">    <param name="savePath">/upload</param>    <result name="success">/welcome.jsp</result></action>

Struts上传文件还是比较简单，只需要在action中申明File属性与其关联，即可。

文件过滤

手动过滤

JAVA文件中

public void validate(){String filterResult=filterTypes(getAllowTypes().split(","));if(filterResult!=null){addFieldError("upload", "上传文件类型不正确");}}public String filterTypes(String[] types){String fileType=getUploadContentType();for(String type:types){if(type.equals(fileType)){return null;}}return ERROR;}

并在配置文件中配置类型

<action name="uploadPro" class="app.action.UploadAction">    <param name="savePath">/upload</param>    <param name="allowTypes">image/png,image/gif,img/jpeg</param>    <result name="success">/welcome.jsp</result>    <result name="error">/error.jsp</result>    <result name="input">/input.jsp</result></action>

如果没通过校验，则在input.jsp页面中通过<s:fielderror />输出异常信息。

拦截器过滤

<action name="uploadPro" class="app.action.UploadAction">    <!-- 配置fileUpload的拦截器 -->    <interceptor-ref name="fileUpload">        <param name="allowedTypes">image/png,image/gif,img/jpeg,img/jpg</param>        <!-- 单位为字节 -->        <param name="maximumSize">200</param>    </interceptor-ref>    <!-- 配置系统默认的拦截器 -->    <interceptor-ref name="defaultStack" />    <param name="savePath">/upload</param>    <result name="success">/welcome.jsp</result>    <result name="error">/error.jsp</result>    <result name="input">/input.jsp</result></action>

在配置文件配置即可。

在过滤文件时，必须显示配置默认的拦截器 defaultStack 并且fileUplaod拦截器必须在defaultStack之前。

文件下载

简单下载实例

public class FileDownAction extends ActionSupport{    private String inputPath;public String getInputPath() {return inputPath;}public void setInputPath(String inputPath) {this.inputPath = inputPath;}    public InputStream getTargetFile(){return ServletActionContext.getServletContext().getResourceAsStream(inputPath);}}

<action name="download" class="app.action.FileDownAction">    <!-- 指定文件下载地址 -->            <param name="inputPath">\images\权限管理功能说明.doc</param>            <result name="success" type="stream">                <!-- 指定文件下载类型 -->                <param name="contentType">doc</param>                <!-- 返回下载文件的信息 -->                <param name="inputName">targetFile</param>                <param name="contentDisposition">filename="sfsfsfs.doc"</param>                <!-- 指定文件缓冲大小 -->                <param name="bufferSize">4096</param>            </result>  </action>