基于Struts2的通用文件上传实现

该文件上传实现可以限制上传文件的类型，限制上传文件的最大字节数，上传文件既可以存储在相对路径下，也可以存储在绝对路径下。

    一、Model类源代码

Java代码
public class Attachments {  
    private long id;  
    private String name;  //文件名  
    private String path;  //上传文件存放的子目录路径  
    private Long fileSize;  //文件大小,单位为K  
    private String contentType; //文件类型  
    private String refName = "attachment"; //引用名称,默认为attachment，可用于区分普通附件与特殊附件。  
    private String entityName; //指定与附件关联的表单的实体名称  
    private String entityId; //指定与附件关联的表单的主键值  
    private String creator; //创建人  
    private Timestamp createDate; //创建时间  
    private File attachFile; //待上传的文件对象  
           ......  
} 

public class Attachments {
private long id;
private String name;  //文件名
private String path;  //上传文件存放的子目录路径
private Long fileSize;  //文件大小,单位为K
private String contentType; //文件类型
private String refName = "attachment"; //引用名称,默认为attachment，可用于区分普通附件与特殊附件。
private String entityName; //指定与附件关联的表单的实体名称
private String entityId; //指定与附件关联的表单的主键值
private String creator; //创建人
private Timestamp createDate; //创建时间
private File attachFile; //待上传的文件对象
           ......
}  

    二、Action类源代码

Java代码
public class UploadAction extends BaseAction {  
    private UploadService uploadService;  
    private Attachments attach;  
      
    //限制  
    private String allowTypes = "";  
    private long maxSize = 0; //字节  
      
    //上传的文件  
    private File upload;  
    private String uploadFileName;  
    private String uploadContentType;  
 
    ......  
 
    //获取与表单关联的所有附件信息  
    public String attachList() throws Exception{  
        List attachList = uploadService.queryAttachments(attach);  
        getValueStack().set("attachList", attachList);  
 
        return SUCCESS;  
    }  
      
    //上传附件  
    public String upload() throws Exception{  
        String method = getRequest().getMethod();  
        if(method.equalsIgnoreCase("post")){  
            if(upload != null){  
                if(upload.length() <= 0){  
                    throw new RuntimeException("上传的文件不能为空！");  
                }  
                if(maxSize > 0 && upload.length() > maxSize){  
                    throw new RuntimeException("上传的文件不能超过" + maxSize + "字节！");  
                }  
                  
                allowTypes = CommonUtil.trim(allowTypes);  
                if(CommonUtil.isNotEmpty(allowTypes)){  
                    int idx = uploadFileName.lastIndexOf(".");  
                    String extendName = uploadFileName.substring(idx+1); //扩展名  
                    List typesList = CommonUtil.toList(allowTypes, ",");  
                    if(!typesList.contains(extendName)){  
                        throw new RuntimeException("只能上传扩展名为[ " + allowTypes + " ]的文件！");  
                    }  
                }  
                  
                attach.setAttachFile(upload);  
                attach.setName(uploadFileName);  
                attach.setFileSize(new Long(upload.length() / 1024)); //K  
                attach.setContentType(uploadContentType);  
                attach.setCreator(SecurityUtil.getUserId());  
                attach.setCreateDate(DatetimeUtil.nowTimestamp());  
                  
                uploadService.addAttachment(attach);  
                  
            }else{  
                return INPUT;  
            }  
        }else{  
            return INPUT;  
        }  
          
        return SUCCESS;  
    }  
      
    //删除附件  
    public String attachDelete() throws Exception{  
        Map map = RequestUtil.getParameterMap(getRequest(), "chk_o_");  
        uploadService.deleteAttachment(map);  
          
        StringBuffer sb = new StringBuffer();  
        sb.append("attachList.action?attach.entityName=" + CommonUtil.trim(attach.getEntityName()));  
        sb.append("&attach.entityId=" + CommonUtil.trim(attach.getEntityId()));  
        sb.append("&attach.refName=" + CommonUtil.trim(attach.getRefName()));  
        sb.append("&attach.path=" + CommonUtil.trim(attach.getPath()));  
        sb.append("&allowTypes=" + CommonUtil.trim(allowTypes));  
        sb.append("&maxSize=" + maxSize);  
          
        getValueStack().set("url", sb.toString());  
          
        return SUCCESS;  
    }  
      
    //下载附件  
    public String download() throws Exception{  
        return SUCCESS;  
    }  
      
    public InputStream getTargetFile() throws Exception{  
        attach = uploadService.getAttachment(attach.getId());  
        uploadFileName = URLEncoder.encode(attach.getName(), "UTF-8"); //解决中文乱码问题  
          
        String filePath = attach.getPath();  
        if(filePath.indexOf(":") == -1){ //相对路径  
            return ServletActionContext.getServletContext().getResourceAsStream(filePath);  
        }else{ //绝对路径  
            return new FileInputStream(filePath);  
        }  
    }  
} 

public class UploadAction extends BaseAction {
private UploadService uploadService;
private Attachments attach;

//限制
private String allowTypes = "";
private long maxSize = 0; //字节

//上传的文件
private File upload;
private String uploadFileName;
private String uploadContentType;

......

//获取与表单关联的所有附件信息
public String attachList() throws Exception{
List attachList = uploadService.queryAttachments(attach);
getValueStack().set("attachList", attachList);

return SUCCESS;
}

//上传附件
public String upload() throws Exception{
String method = getRequest().getMethod();
if(method.equalsIgnoreCase("post")){
if(upload != null){
if(upload.length() <= 0){
throw new RuntimeException("上传的文件不能为空！");
}
if(maxSize > 0 && upload.length() > maxSize){
throw new RuntimeException("上传的文件不能超过" + maxSize + "字节！");
}

allowTypes = CommonUtil.trim(allowTypes);
if(CommonUtil.isNotEmpty(allowTypes)){
int idx = uploadFileName.lastIndexOf(".");
String extendName = uploadFileName.substring(idx+1); //扩展名
List typesList = CommonUtil.toList(allowTypes, ",");
if(!typesList.contains(extendName)){
throw new RuntimeException("只能上传扩展名为[ " + allowTypes + " ]的文件！");
}
}

attach.setAttachFile(upload);
attach.setName(uploadFileName);
attach.setFileSize(new Long(upload.length() / 1024)); //K
attach.setContentType(uploadContentType);
attach.setCreator(SecurityUtil.getUserId());
attach.setCreateDate(DatetimeUtil.nowTimestamp());

uploadService.addAttachment(attach);

}else{
return INPUT;
}
}else{
return INPUT;
}

return SUCCESS;
}

//删除附件
public String attachDelete() throws Exception{
Map map = RequestUtil.getParameterMap(getRequest(), "chk_o_");
uploadService.deleteAttachment(map);

StringBuffer sb = new StringBuffer();
sb.append("attachList.action?attach.entityName=" + CommonUtil.trim(attach.getEntityName()));
sb.append("&attach.entityId=" + CommonUtil.trim(attach.getEntityId()));
sb.append("&attach.refName=" + CommonUtil.trim(attach.getRefName()));
sb.append("&attach.path=" + CommonUtil.trim(attach.getPath()));
sb.append("&allowTypes=" + CommonUtil.trim(allowTypes));
sb.append("&maxSize=" + maxSize);

getValueStack().set("url", sb.toString());

return SUCCESS;
}

//下载附件
public String download() throws Exception{
return SUCCESS;
}

public InputStream getTargetFile() throws Exception{
attach = uploadService.getAttachment(attach.getId());
uploadFileName = URLEncoder.encode(attach.getName(), "UTF-8"); //解决中文乱码问题

String filePath = attach.getPath();
if(filePath.indexOf(":") == -1){ //相对路径
return ServletActionContext.getServletContext().getResourceAsStream(filePath);
}else{ //绝对路径
return new FileInputStream(filePath);
}
}
}

   三、Service类源代码

Java代码
public class UploadService extends BaseService {  
    /** 
     * 保存附件信息并将附件文件存储到指定目录下 
     */ 
    public void addAttachment(Attachments attach)throws Exception{  
        if(CommonUtil.isEmpty(attach.getRefName())) attach.setRefName("attachment");  
          
        //文件存储基路径  
        String path = CommonUtil.trim(attach.getPath());  
        if(CommonUtil.isNotEmpty(path)){  
            if(path.endsWith("/") == false && path.endsWith("\\") == false){  
                path += File.separator;  
            }  
            if(path.startsWith("/")==false && path.startsWith("\\")==false){  
                if(Constants.attachBasePath.endsWith("/")==false && Constants.attachBasePath.endsWith("\\")==false){  
                    path = File.separator + path;  
                }  
            }  
        }  
        path = Constants.attachBasePath + path;  
        attach.setPath(path);  
          
        save(attach);  
          
        //文件存储路径  
        if(path.endsWith("/") == false && path.endsWith("\\") == false){  
            path += File.separator;  
        }  
        path += attach.getId() + "_o_" + attach.getName();  
        attach.setPath(path);  
        update(attach);  
          
        //目标文件  
        String filePath = path;  
        if(filePath.indexOf(":") == -1) filePath = ServletActionContext.getRequest().getRealPath(filePath); //不是绝对路径就转成绝对路径  
          
        File dstFile = new File(filePath);  
        FileUtil.createPath(dstFile.getParent()); //目标目录不存在时创建  
          
        //文件保存  
        try{  
            FileUtil.copyFile(attach.getAttachFile(), dstFile);  
        }catch(FileNotFoundException ex){  
            throw new ServiceException("文件不存在：" + attach.getName());  
        }  
    }  
      
    /** 
     * 删除选中的附件信息及其对应的文件 
     */ 
    public void deleteAttachment(Map map) throws ServiceException{  
        List pathList = new ArrayList();  
          
        for(Iterator it=map.keySet().iterator();it.hasNext();){  
            String key = (String)it.next();  
            String value = (String)map.get(key);  
              
            Attachments attach = (Attachments)load(Attachments.class, new Long(value));  
            if(attach != null){  
                pathList.add(attach.getPath());  
                delete(attach);  
            }  
        }  
          
        for(int i=0;i<pathList.size();i++){  
            String filePath = (String)pathList.get(i);  
            if(filePath.indexOf(":") == -1){  
                filePath = ServletActionContext.getRequest().getRealPath(filePath);  
            }  
            File file = new File(filePath);  
            FileUtil.deleteFile(file);  
        }  
    }  
      
    /** 
     * 查找附件 
     */ 
    public List queryAttachments(Attachments attach)throws Exception{  
        DetachedCriteria dc = DetachedCriteria.forClass(Attachments.class);  
        CriteriaUtil.eq(dc, "entityName", attach.getEntityName());  
        CriteriaUtil.eq(dc, "entityId", attach.getEntityId());  
        CriteriaUtil.eq(dc, "refName", attach.getRefName());  
 
        dc.addOrder(Order.asc("createDate"));  
          
        return findByCriteria(dc);  
    }  
      
    public Attachments getAttachment(long id)throws Exception{  
        return (Attachments)load(Attachments.class, new Long(id));  
    }  
}