jsf文件上传，seam的文件上传

a.jsf文件上传:
实现jsf应用的文件上传功能，可以使用MyFaces文件上传组件
依赖的库有 commons-io.jar，myfaces-api.jar，myfaces-impl.jar，tomahawk.jar
web.xml:
 <filter>
   <filter-name>MyfacesExtensionsFilter</filter-name>
   <filter-class>
    org.apache.myfaces.webapp.filter.ExtensionsFilter
   </filter-class>
   <init-param>
    <param-name>uploadMaxFileSize</param-name>
    <param-value>10m</param-value>
   </init-param>
   <init-param>
    <param-name>uploadThresholdSize</param-name>
    <param-value>50k</param-value>
   </init-param>
   <init-param>
    <param-name>uploadRepositoryPath</param-name>
    <param-value>../</param-value>
   </init-param>
 </filter>

 <filter-mapping>
  <filter-name>MyfacesExtensionsFilter</filter-name>
  <servlet-name>Faces Servlet</servlet-name>
 </filter-mapping>
 <filter-mapping>
  <filter-name>MyfacesExtensionsFilter</filter-name>
  <url-pattern>/faces/myFacesExtensionResource/*</url-pattern>
 </filter-mapping>

 ////////////////////////////////
 其他的jsf 和 myFaces 配置就不写在这里了

 //////////////////////////////////

entity:student
public class Student{
 public Student(){
 }

 private byte[] stuFileData;
 private String stuFileName;

 public void setStuFuleData(byte[] stuFileData){
  this.stuFileData = stuFileData;
 }
 public byte[] getStuFileData(){
  return this.stuFileData;
 }
 public void setStuFileName(String stuFileName){
  this.stuFileName = stuFileName;
 }
 public String getStuFileName(){
  return this.stuFileName;
 }
 }
 受管bean:StudentAction

 import org.apache.myfaces.custom.fileupload.UploadedFile;

 public StudentAction{
 private UploadedFile _upFile;

 public String addStudent(){
   // 获得文件的全名，含路径
  String fileName = _upFile.getName();
  if (!fileName.equals("")) {
   File temp = new File(fileName);
   // 获得文件名
   fileName = temp.getName();
  }
  byte[] buffer = new byte[new Long(_upFile.getSize()).intValue()];
  try {
   buffer = _upFile.getBytes();
  } catch (IOException e) {
   e.printStackTrace();
  }

  Student student = new Student();
  student.setStuDataName(fileName);
  student.setStuDataFileData(buffer);

  //studentDAO.save(student);
  return null;
 }

 public String down(){
  try {
   //先检索student
   Student student = stdentDAO.getStudent();

   System.err.println("...................in...............");
   FacesContext ctx = FacesContext.getCurrentInstance();
   HttpServletResponse response = (HttpServletResponse)ctx.getExternalContext().getResponse();
   String contentType = "application/x-msdownload;charset=utf-8";
   response.setContentType(contentType);
   response.setHeader("Content-disposition", "attachment; filename=\"" +student.getStuFileName+"\"");
   ServletOutputStream out = response.getOutputStream();  
   if(null!=crFile)
   out.write(crFile);
   out.flush();
   ctx.responseComplete();
  } catch (Exception e) {
   e.printStackTrace();
  }
  
  return null;
 }

 public UploadedFile get_upFile() {
  return _upFile;
 }

 public void set_upFile(UploadedFile file) {
  _upFile = file;
 }
 }

jsp:
首先引入标签
<%@ taglib uri="http://myfaces.apache.org/tomahawk" prefix="t"%>
 <h:form id="from" enctype="multipart/form-data">
 <t:inputFileUpload id="fileupload" value="#{StudentAction._upFile}"/>
 <h:commandButton action="StudentAction.addStudent" value="保存"/>
 <h:commandButton action="StudentAction.down" value="下载附件"/>
</h:form>

以上程序未经调试，运行时可能会出现错误，不过用 myFaces 实现 jsf 的文件上传功能
需要注意的要点和关键性代码都已将完成了。
b.seam 的文件上传
  seam应用的文件上传也可以使用 myFaces，使用方法和上面相同。
  不过seam自身也提供了附件上传的组件功能，而且实现起来更简单:
  xhtml文件:
  首先引入标签
  xmlns:s="http://jboss.com/products/seam/taglib"
  <h:form id="from" enctype="multipart/form-data">
   <s:fileUpload id="myFile" fileName="#{student.stuFileName}" data="#{student.stuFileData}"/>
   <a4j:commandButton value="保存" action="#{StudentAction.addStuent}"/>
   <a4j:commandButton value="下载附件" action="#{StudentAction.down}"/>
  </h:form>

 受管bean:StudentAction

 import org.apache.myfaces.custom.fileupload.UploadedFile;

 public StudentAction{
 private Student student;
 @In(request=false,create=true)
 @Out(request=false)
 public String addStudent(){
  //studentDAO.save(student);
  return null;
 }

 public String down(){
  try {
   //先检索student
   Student student = stdentDAO.getStudent();
   FacesContext ctx = FacesContext.getCurrentInstance();
   HttpServletResponse response = (HttpServletResponse)ctx.getExternalContext().getResponse();
   String contentType = "application/x-msdownload;charset=utf-8";
   response.setContentType(contentType);
   response.setHeader("Content-disposition", "attachment; filename=\""   +student.getStuFileName+"\"");
   ServletOutputStream out = response.getOutputStream();  
   if(null!=crFile)
   out.write(crFile);
   out.flush();
   ctx.responseComplete();
  } catch (Exception e) {
   e.printStackTrace();
  }
  
  return null;
 }
 }

entity:student
@Name("student")
public class Student{
 public Student(){
 }

 private byte[] stuFileData;
 private String stuFileName;
 
 public void setStuFuleData(byte[] stuFileData){
  this.stuFileData = stuFileData;
 }

 @Column(name="StuFileData",length=2147483647)
 @Basic(fetch=FetchType.LAZY)
 @Lob
 public byte[] getStuFileData(){
  return this.stuFileData;
 }
 public void setStuFileName(String stuFileName){
  this.stuFileName = stuFileName;
 }
 @Column(name = "StuFileName", length = 100)
 @Length(max = 100)
 public String getStuFileName(){
  return this.stuFileName;
 }
 }

特别注意 jsp form 的提交方式
<h:form id="from" enctype="multipart/form-data">
否则fileData不能传递到受管 bean