在Struts2中实现文件上传

其次是FileUploadAction.java代码：

package tuTorial;import java.io.BufferedInputStream;import java.io.BufferedOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStream;import java.io.OutputStream;import java.util.Date;import org.apache.struts2.ServletActionContext;import com.opensymphony.xwork2.ActionSupport;public class FileUploadAction extends ActionSupport　{private static final long serialVersionUID = 572146812454l ;private static final int BUFFER_SIZE = 16 * 1024 ;private File myFile;private String contentType;private String fileName;private String imageFileName;private String caption;public void setMyFileContentType(String contentType)　{this .contentType = contentType;}public void setMyFileFileName(String fileName)　{this .fileName = fileName;}public void setMyFile(File myFile)　{this .myFile = myFile;}public String getImageFileName()　{return imageFileName;}public String getCaption()　{return caption;}public void setCaption(String caption)　{this .caption = caption;}private static void copy(File src, File dst)　{try　{InputStream in = null ;OutputStream ut = null ;try　{in = new BufferedInputStream( new FileInputStream(src), BUFFER_SIZE);ut = new BufferedOutputStream( new FileOutputStream(dst), BUFFER_SIZE);byte [] buffer = new byte [BUFFER_SIZE];while (in.read(buffer) > 0 )　{out.write(buffer);}} finally　{if ( null != in)　{in.close();}if ( null != out)　{out.close();}}} catch (Exception e)　{e.printStackTrace();}}private static String getExtention(String fileName)　{int pos = fileName.lastIndexOf( " . " );return fileName.substring(pos);}@Overridepublic String execute()　　　{imageFileName = new Date().getTime() + getExtention(fileName);File imageFile = new File(ServletActionContext.getServletContext().getRealPath( " /UploadImages " ) + " / " + imageFileName);copy(myFile, imageFile);return SUCCESS;}}

清单3 tuTorial/FileUploadAction.java

在FileUploadAction中我分别写了setMyFileContentType、setMyFileFileName、setMyFile和setCaption四个Setter方法，后两者很容易明白，分别对应FileUpload.jsp中的和标志。但是前两者并没有显式地与任何的页面标志绑定，那么它们的值又是从何而来的呢？其实，标志不仅仅是绑定到myFile，还有myFileContentType（上传文件的MIME类型）和myFileFileName（上传文件的文件名，该文件名不包括文件的路径）。因此，对应Action类里面的xxx、xxxContentType和xxxFileName三个属性。