java word 附件 流式下载 java下载邮件附件

      上一篇博文是生成pdf文档， 这篇文档跟大家分享一下怎么发送邮件，并且实现pdf作为附件的功能。

     javaEmail的maven形式的jar包：

<dependency>
    <groupId>javax.mail</groupId>
    <artifactId>mail</artifactId>
    <version>1.4</version>
</dependency>

首先是实现邮件发送功能的代码:

 

public void sendEmailAndPDF(SendEmailAndPDFReuqest sendEmailAndPDFReuqest, String fileLocalName) throws Exception {
		logger.error("sendEmailAndPDF is keep on.....and fileLocalName is "+fileLocalName+"request is "+JsonUtils.objectToJson(sendEmailAndPDFReuqest));
		EmailMessage emailMessage = new EmailMessage();
		StringBuffer sb = new StringBuffer();
		String orderNo = sendEmailAndPDFReuqest.getResp().getMainOrderNo();
		sb.append(orderNo);
		emailMessage.setSubject(String.format("订单号：%s预订确认", sb)); //邮箱标题
		emailMessage.setContext(sendOrderDeatilAndPDFContext.buildContext(sendEmailAndPDFReuqest));//邮箱正文，我这个正文很简单，就不上代码了，就是一些html标签+文字描述
		emailMessage.setBodyHtml(true);
		Vector<String> file = new Vector<String>();//保存多个需上传附件的文件名
		file.add(fileLocalName);
		emailMessage.setFile(file);
		emailProvider.sendEmailAndPDF(emailMessage, sendEmailAndPDFReuqest.getResp().getSupplier(),sendEmailAndPDFReuqest.getProviderEmail());
	}
	
	email.setEmailReceiver(); //设置邮箱接收者
	sendEmail(email);
      //下面是主要的发送代码：
	private String host = "smtp.****.com.cn"; //这是smtp协议的邮箱服务器主机，每个公司都不一样
 	
	private int port = 27; 
	
	private String auth = "true";
	
	private String userName = "frank.***@****.com"; //公司哟向服务器主机的账号
	
	private String password = ""; //密码
	
	private String sendMailAddress = "****"; //发送的邮件名，一般的用公司名义去申请的邮箱
	
    Logger logger = LoggerFactory.getLogger(this.getClass());
	
	public void sendEmail(EmailMessage email) throws Exception{
		logger.error("createSendEmail is starting........email is "+JsonUtils.objectToJson(email));
		System.setProperty("mail.mime.charset","UTF-8");
		Properties props = new Properties();
    		props.put("mail.smtp.host", host);
    		props.put("mail.smtp.port", port);
    		props.put("mail.smtp.auth", auth);
    		Session s = Session.getInstance(props);
    		MimeMessage message = new MimeMessage(s);
    		InternetAddress from = new InternetAddress(sendMailAddress);
    		message.setFrom(from);
    		message.addRecipients(Message.RecipientType.TO, email.getAddress());//邮箱接收者
    		message.setSubject(email.getSubject());
    		message.setSentDate(new Date());
    		Multipart mp = new MimeMultipart();
    		if(!email.getFile().isEmpty()){//有附件  
    	        Enumeration<String> efile=email.getFile().elements();  
    	        while(efile.hasMoreElements()){   
    	        	MimeBodyPart mbp=new MimeBodyPart();  
    	            String filename=efile.nextElement(); //选择出每一个附件名  
    	            FileDataSource fds= new FileDataSource(filename); //得到数据源  
    	            mbp.setDataHandler(new DataHandler(fds)); //得到附件本身并至入BodyPart  
    	            mbp.setFileName(MimeUtility.encodeText(fds.getName()));  //得到文件名同样至入BodyPart  
    	            mp.addBodyPart(mbp);  
    	        }    
    	        email.getFile().removeAllElements();      
    	    }	
    		if (email.isBodyHtml()) {
    			MimeBodyPart mbp = new MimeBodyPart();
    			mbp.setContent(email.getContext(), "text/html;charset=utf-8");
    			mp.addBodyPart(mbp);
    			message.setContent(mp);
    		} else{
    			MimeBodyPart mbp = new MimeBodyPart();
    			mbp.setContent(email.getContext(), "text/plain;charset=utf-8");
    			mp.addBodyPart(mbp);
    			message.setContent(mp);
    		}
    		message.saveChanges();
    		Transport transport = s.getTransport("smtp");//创建邮箱服务器通道的协议
    		transport.connect(host, port, userName, password);//设置连接的主机号端口号账号和密码
    		logger.error(" and  message.getAllRecipients is "+ message.getAllRecipients() != null ? JsonUtils.objectToJson(message.getAllRecipients()):"");
    		transport.sendMessage(message, message.getAllRecipients());
    		transport.close();
    		logger.info("email send tips: email from " + userName + " to " + email.getEmailReceiver());
	}

          这样就能完成一个邮箱发送的基础功能，下面就来看看怎么讲在代码中生成的pdf发到附件中？
          其实上面的代码已经实现了。
          因为之前已经生成了pdf文档，但是并没有在没有返回页面之前，还是在response中的输出流中，但是Email的的实体类只接受文件名的形式，

         之前想过将response中的输出流转换成输入流或者字节流来做, 转换成字节流的byteinputstream只能从高速缓存中读取, 而httpservletReponse中读取不到, 
          这边用的办法是将response先写到默认的文件路中 System.getProperty("java.io.tmpdir");

   就是在系统的C:\Users\mars\AppData\Local\Temp,这个地址是jvm默认的临时文件存放地址,

         上一篇文章有这一步，如下: 将pdfWrite写入文件输入流中输出到系统临时文件地址下,

FileOutputStream fos = new FileOutputStream(file);     	
if(type.equals(DOWNLOAD_PDF)){  
            PdfWriter.getInstance(document, response.getOutputStream());//用于返回页面下载  
        }else if(type.equals(SEND_PDF)){  
            PdfWriter.getInstance(document, fos);//用于邮件附件获取  
        }
Vector<String> file = new Vector<String>();//保存多个需上传附件的文件名
file.add(fileLocalName);
emailMessage.setFile(file);
    通过方法去获取对应文件名和地址的文件作为附件,实现了附件上传
   
if(!email.getFile().isEmpty()){//有附件  
    Enumeration<String> efile=email.getFile().elements();  
    	while(efile.hasMoreElements()){   
    	     MimeBodyPart mbp=new MimeBodyPart();  
    	     String filename=efile.nextElement(); //选择出每一个附件名  
    	     FileDataSource fds= new FileDataSource(filename); //得到数据源  
    	     mbp.setDataHandler(new DataHandler(fds)); //得到附件本身并至入BodyPart  
    	     mbp.setFileName(MimeUtility.encodeText(fds.getName()));   
    	     mp.addBodyPart(mbp);  
    	   }    
    	email.getFile().removeAllElements(); }