java中使用restful web service来传输文件

【1】上传大文件：

	前端页面：  
		1)同步上传：
			  
				  
					
  
					  
					  
					  
					
  
				  
			  
	  
		2)异步上传：
			
			
				
					
					
				
				
					
  
						  上传文件：	
										  
					
  
					
					
					
				
			
		  
		  
	后端：  
	  
		web.xml  
			  
				CXFServlet  
				org.apache.cxf.transport.servlet.CXFServlet  
				1   
			  
			  
				CXFServlet  
				/api/*  
			  
	  
		Spring配置文件：  
			  
				  
					  
				  
				  
					  
				  
			  
			  
			  
			  
			  
		接口：  
			import org.apache.cxf.jaxrs.ext.multipart.Attachment;  
			import org.apache.cxf.jaxrs.ext.multipart.Multipart;  
		  
			@Path("")  
			public interface ApiFileProcessService {  
				@POST  
				@Path("/uploadFile")  
				@Consumes(MediaType.MULTIPART_FORM_DATA)  
				public String uploadFile(@Multipart(value="targetFile")Attachment targetFile, @Multipart(value="userName")String userName);  
			}  
		  
		实现：  
			import org.apache.cxf.jaxrs.ext.multipart.Attachment;  
			import javax.activation.DataHandler;  
		  
			public class ApiFileProcessServiceImpl implements ApiFileProcessService {  
				  
				@Override  
				public String uploadFile(Attachment targetFile, String userName) {  
					  
					try {  
						DataHandler dataHandler = targetFile.getDataHandler();  
						String originalFileName = new String(dataHandler.getName().getBytes("ISO8859-1"),"UTF-8");  
						InputStream is = dataHandler.getInputStream();  
						  
						SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");  
						String saveLocation = "D:\\" + df.format(new Date()) + "_" + originalFileName;  
								  
						OutputStream out = new FileOutputStream(new File(saveLocation));  
						int read = 0;  
						byte[] bytes = new byte[4096];  
						while ((read = is.read(bytes)) != -1) {  
							out.write(bytes, 0, read);  
						}  
						out.flush();  
						out.close();  
						  
					} catch (Exception e) {  
						e.printStackTrace();  
					}  
					  
					return "success";  
				}  
			}  
			  
		测试结果：可以轻松处理(上传)1G以上的文件。		
			  
      
【2】上传小文件：

	前端页面： 
		
		
			

			
			
			
			
		
		

	后端：  
	  
		接口： 
			import javax.ws.rs.core.Context;
			
			@Path("")  
			public interface ApiFileProcessService {  
				@POST
				@Path("/uploadCommonFile")
				@Consumes(MediaType.MULTIPART_FORM_DATA)
				public String uploadCommonFile(@Context HttpServletRequest request);
			}
			
		实现：
			import org.apache.commons.fileupload.FileItem;
			import org.apache.commons.fileupload.disk.DiskFileItemFactory;
			import org.apache.commons.fileupload.servlet.ServletFileUpload;
		  
			public class ApiFileProcessServiceImpl implements ApiFileProcessService {  
				@Override
				public String uploadCommonFile(HttpServletRequest request) {

					try {
						DiskFileItemFactory factory = new DiskFileItemFactory();
						ServletFileUpload fileUpload = new ServletFileUpload(factory);
						List items = fileUpload.parseRequest(request);

						for (FileItem item : items) {
							if (!item.isFormField()) {
								String originalFileName = item.getName();
								
								SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");  
								String saveLocation = "D:\\" + df.format(new Date()) + "_" + originalFileName;  
								
								File picFile = new File(saveLocation);
								item.write(picFile);
							}
						}
					} catch (Exception e) {
						e.printStackTrace();
					}

					return "success";
				}
			} 


	注意：此方法仅适合上传小文件。


【3】下载文件
	case1：
		接口：	
			import javax.ws.rs.GET;
			import javax.ws.rs.QueryParam;

			@Path("")  
			public interface ApiFileProcessService {  
				@GET
				@Path("/downloadTemplate")
				public Response downloadTemplate(@QueryParam("templateName")templateName );
			}
			
		实现：
			import javax.ws.rs.core.Response;
			import javax.ws.rs.core.Response.ResponseBuilder;
			
			public class ApiFileProcessServiceImpl implements ApiFileProcessService {  
			
				@Override
				public Response downloadTemplate(String templateName) {

					File file = null;
					String fileName = null;
					
					try {
						String applicationPath = Thread.currentThread().getContextClassLoader().getResource("").toURI().getPath();

						file = new File(applicationPath + "/" + templateName);

						fileName = URLEncoder.encode(templateName, "UTF-8"); // 如果不进行编码，则下载下来的文件名称是乱码
						
					} catch (Exception e) {
						e.printStackTrace();
						return Response.status(Response.Status.INTERNAL_SERVER_ERROR).entity(e.getMessage()).build();
					}
					
					ResponseBuilder response = Response.ok((Object) file);
					response.header("Content-Disposition", "attachment; filename=" + fileName);

					return response.build();
				}
			}
			
			
			
	case2：	
		接口：
			
			import javax.ws.rs.*;
			import javax.ws.rs.core.Context;
			
			@GET
			@Path("/exportTest")
			@Produces("application/vnd.ms-excel")
			public Response exportTest(@FormParam("str") String str, @Context HttpServletResponse response);
			
		实现：
			import javax.ws.rs.core.Response;
			import javax.servlet.http.HttpServletResponse;
		
			@Override
			public Response exportTest(String str, HttpServletResponse response) {

				try {
					ServletOutputStream outputStream = response.getOutputStream();

					SXSSFWorkbook wb = new SXSSFWorkbook();
					wb.setCompressTempFiles(true);

					Sheet sheet = wb.createSheet("sheet0");
					Row row = sheet.createRow(0);
					row.createCell(0).setCellValue("hahaha");

					wb.write(outputStream);

					response.setHeader("content-disposition", "attachment;filename=" + URLEncoder.encode("中文名字.xlsx", "UTF-8"));
					response.setContentType("application/vnd.ms-excel");
					outputStream.close();

				} catch (IOException e) {
					e.printStackTrace();
				}

				return null;
			}