javamail - 拉取邮件 - 番外

一. 邮件拉取其他工具类

package com.vevor.crm.utils;

import lombok.extern.log4j.Log4j2;
import org.apache.commons.lang3.StringUtils;

import javax.mail.*;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * @Description: 解析邮件工具类
 * @Author: xyw
 * @CreateDt: 2019-05-07
 */
@Log4j2
public class AnalysisEmailUtil {

    /**
     * 获得邮件主题
     *
     * @param msg 邮件内容
     * @return 解码后的邮件主题
     */
    public static String getSubject(MimeMessage msg) throws UnsupportedEncodingException, MessagingException {
        // 非空判断, 防止NPE
        if (msg == null) {
            return StringUtils.EMPTY;
        } else {
            if (StringUtils.isNotBlank(msg.getSubject())) {
                return MimeUtility.decodeText(msg.getSubject());
            } else {
                return StringUtils.EMPTY;
            }
        }
    }

    /**
     * 获得邮件发件人
     *
     * @param msg 邮件内容
     * @return 姓名 <Email地址>
     * @throws FolderClosedException
     * @throws MessagingException
     * @throws UnsupportedEncodingException
     */
    public static String getFrom(MimeMessage msg) throws FolderClosedException, MessagingException, UnsupportedEncodingException {
        String from = "";
        Address[] froms = msg.getFrom();
        if (froms == null || froms.length < 1) {
            return from;
        }

        InternetAddress address = (InternetAddress) froms[0];
        String person = address.getPersonal();
        if (person != null) {
            person = MimeUtility.decodeText(person) + " ";
        } else {
            person = "";
        }
        from = person + "<" + address.getAddress() + ">";

        return from;
    }

    /**
     * 获取发件人邮箱地址
     *
     * @param msg
     * @return
     * @throws MessagingException
     * @throws UnsupportedEncodingException
     */
    public static String getFromAddress(MimeMessage msg) throws MessagingException, UnsupportedEncodingException {

        Address[] froms = msg.getFrom();
        if (froms == null || froms.length < 1) {
            return StringUtils.EMPTY;
        }

        InternetAddress address = (InternetAddress) froms[0];

        return address.getAddress();
    }

    /**
     * 获取发件人名字信息
     *
     * @param msg
     * @return
     * @throws MessagingException
     * @throws UnsupportedEncodingException
     */
    public static String getFromPerson(MimeMessage msg) throws MessagingException, UnsupportedEncodingException {

        Address[] froms = msg.getFrom();
        if (froms == null || froms.length < 1) {
            return StringUtils.EMPTY;
        }

        InternetAddress fromAddress = (InternetAddress) froms[0];
        String personName = fromAddress.getPersonal();
        if (personName != null) {
            personName = MimeUtility.decodeText(personName) + " ";
        } else {
            personName = "";
        }

        return personName;
    }

    /**
     * 根据收件人类型,获取邮件收件人、抄送和密送地址。如果收件人类型为空,则获得所有的收件人
     * <p>Message.RecipientType.TO  收件人</p>
     * <p>Message.RecipientType.CC  抄送</p>
     * <p>Message.RecipientType.BCC 密送</p>
     *
     * @param msg  邮件内容
     * @param type 收件人类型
     * @return 收件人1 <邮件地址1>, 收件人2 <邮件地址2>, ...
     * @throws MessagingException
     */
    public static String getReceiveAddress(MimeMessage msg, Message.RecipientType type) throws MessagingException {
        StringBuffer receiveAddress = new StringBuffer();
        Address[] addresss = null;
        if (type == null) {
            addresss = msg.getAllRecipients();
        } else {
            addresss = msg.getRecipients(type);
        }

        if (addresss == null || addresss.length < 1) {
            return StringUtils.EMPTY;
        }

        for (Address address : addresss) {
            InternetAddress internetAddress = (InternetAddress) address;
            receiveAddress.append(internetAddress.getAddress()).append(",");
        }

        receiveAddress.deleteCharAt(receiveAddress.length() - 1);    //删除最后一个逗号

        return receiveAddress.toString();
    }

    /**
     * 获得邮件发送时间
     *
     * @param msg 邮件内容
     * @return yyyy年mm月dd日 星期X HH:mm
     * @throws MessagingException
     */
    public static String getSentDate(MimeMessage msg, String pattern) throws MessagingException {
        Date receivedDate = msg.getSentDate();
        if (receivedDate == null) {
            return StringUtils.EMPTY;
        }

        if (pattern == null || "".equals(pattern)) {
            pattern = "yyyy年MM月dd日 E HH:mm ";
        }

        return new SimpleDateFormat(pattern).format(receivedDate);
    }

    /**
     * 判断邮件中是否包含附件
     *
     * @param part
     * @return 邮件中存在附件返回true,不存在返回false
     * @throws MessagingException
     * @throws IOException
     */
    public static boolean isContainAttachment(Part part) throws MessagingException, IOException {
        boolean flag = false;
        if (part.isMimeType("multipart/*")) {
            MimeMultipart multipart = (MimeMultipart) part.getContent();
            int partCount = multipart.getCount();
            for (int i = 0; i < partCount; i++) {
                BodyPart bodyPart = multipart.getBodyPart(i);
                String disp = bodyPart.getDisposition();
                if (disp != null && (disp.equalsIgnoreCase(Part.ATTACHMENT) || disp.equalsIgnoreCase(Part.INLINE))) {
                    flag = true;
                } else if (bodyPart.isMimeType("multipart/*")) {
                    flag = isContainAttachment(bodyPart);
                } else {
                    String contentType = bodyPart.getContentType();
                    if (contentType.indexOf("application") != -1) {
                        flag = true;
                    }

                    if (contentType.indexOf("name") != -1) {
                        flag = true;
                    }
                }

                if (flag) {
                    break;
                }
            }
        } else if (part.isMimeType("message/rfc822")) {
            flag = isContainAttachment((Part) part.getContent());
        }
        return flag;
    }

    /**
     * 判断邮件是否已读
     *
     * @param msg 邮件内容
     * @return 如果邮件已读返回true, 否则返回false
     * @throws MessagingException
     */
    public static boolean isSeen(MimeMessage msg) throws MessagingException {
        return msg.getFlags().contains(Flags.Flag.SEEN);
    }

    /**
     * 判断邮件是否需要阅读回执
     *
     * @param msg 邮件内容
     * @return 需要回执返回true, 否则返回false
     * @throws MessagingException
     */
    public static boolean isReplySign(MimeMessage msg) throws MessagingException {
        boolean replySign = false;
        String[] headers = msg.getHeader("Disposition-Notification-To");
        if (headers != null) {
            replySign = true;
        }
        return replySign;
    }

    /**
     * 获得邮件文本内容
     *
     * @param part    邮件体
     * @param content 存储邮件文本内容的字符串
     * @throws MessagingException
     * @throws IOException
     */
    public static void getMailTextContent(Part part, StringBuffer content) throws MessagingException, IOException {
        //如果是文本类型的附件,通过getContent方法可以取到文本内容,但这不是我们需要的结果,所以在这里要做判断
        boolean isContainTextAttach = part.getContentType().indexOf("name") > 0;
        if (part.isMimeType("text/*") && !isContainTextAttach) {
            content.delete(0,content.length());
            content.append(part.getContent().toString());
        } else if (part.isMimeType("message/rfc822")) {
            getMailTextContent((Part) part.getContent(), content);
        } else if (part.isMimeType("multipart/*")) {
            Multipart multipart = (Multipart) part.getContent();
            int partCount = multipart.getCount();
            for (int i = 0; i < partCount; i++) {
                BodyPart bodyPart = multipart.getBodyPart(i);
                content.delete(0,content.length());
                getMailTextContent(bodyPart, content);
            }
        }
    }

    /**
     * 保存附件
     *
     * @param part    邮件中多个组合体中的其中一个组合体
     * @param destDir 附件保存目录
     * @throws UnsupportedEncodingException
     * @throws MessagingException
     * @throws FileNotFoundException
     * @throws IOException
     */
    public static String saveAttachment(Part part, String destDir) throws UnsupportedEncodingException, MessagingException,
            FileNotFoundException, IOException {
        StringBuilder attachPath = new StringBuilder();
        if (part.isMimeType("multipart/*")) {
            Multipart multipart = (Multipart) part.getContent();    //复杂体邮件
            //复杂体邮件包含多个邮件体
            int partCount = multipart.getCount();
            for (int i = 0; i < partCount; i++) {
                //获得复杂体邮件中其中一个邮件体
                BodyPart bodyPart = multipart.getBodyPart(i);
                //某一个邮件体也有可能是由多个邮件体组成的复杂体
                String disp = bodyPart.getDisposition();
                if (disp != null && (disp.equalsIgnoreCase(Part.ATTACHMENT) || disp.equalsIgnoreCase(Part.INLINE))) {
                    InputStream is = bodyPart.getInputStream();
                    saveFile(is, destDir, decodeText(bodyPart.getFileName()), attachPath);
                } else if (bodyPart.isMimeType("multipart/*")) {
                    saveAttachment(bodyPart, destDir);
                } else {
                    String contentType = bodyPart.getContentType();
                    if (contentType.indexOf("name") != -1 || contentType.indexOf("application") != -1) {
                        saveFile(bodyPart.getInputStream(), destDir, decodeText(bodyPart.getFileName()), attachPath);
                    }
                }
            }
        } else if (part.isMimeType("message/rfc822")) {
            saveAttachment((Part) part.getContent(), destDir);
        }
        // 判断是否有文件路径生成
        if (attachPath.length() > 0) {
            return attachPath.toString();
        }

        return StringUtils.EMPTY;
    }

    /**
     * 读取输入流中的数据保存至指定目录
     *
     * @param is        输入流
     * @param destDir   文件存储目录
     * @param fileName  文件名
     * @param attachPath
     * @throws FileNotFoundException
     * @throws IOException
     */
    private static void saveFile(InputStream is, String destDir, String fileName, StringBuilder attachPath)
            throws FileNotFoundException, IOException {
        // 判断filename是否有效
        if (StringUtils.isBlank(fileName)) {
            // 直接返回
            return;
        }
        File file = new File(destDir + fileName);
        // 设置文件最后路径
        attachPath.append(destDir + fileName).append(",");
        if (!file.exists()){
            BufferedInputStream bis = new BufferedInputStream(is);
            BufferedOutputStream bos = new BufferedOutputStream(
                    new FileOutputStream(file));
            int len = -1;
            while ((len = bis.read()) != -1) {
                bos.write(len);
                bos.flush();
            }
            bos.close();
            bis.close();
        }
    }

    /**
     * 文本解码
     *
     * @param encodeText 解码MimeUtility.encodeText(String text)方法编码后的文本
     * @return 解码后的文本
     * @throws UnsupportedEncodingException
     */
    public static String decodeText(String encodeText) throws UnsupportedEncodingException {
        if (encodeText == null || "".equals(encodeText)) {
            return "";
        } else {
            return MimeUtility.decodeText(encodeText);
        }
    }

    /**
     * 发件箱附件解析方法
     *
     * @param part
     * @param destDir
     * @return
     * @throws UnsupportedEncodingException
     * @throws MessagingException
     * @throws IOException
     */
    public static String saveAttachmentForSend(Part part, String destDir) throws UnsupportedEncodingException, MessagingException, IOException {
        StringBuilder attchPath = new StringBuilder();
        if (part.isMimeType("multipart/*")) {
            Multipart multipart = (Multipart) part.getContent();    //复杂体邮件
            //复杂体邮件包含多个邮件体
            int partCount = multipart.getCount();
            for (int i = 0; i < partCount; i++) {
                //获得复杂体邮件中其中一个邮件体
                BodyPart bodyPart = multipart.getBodyPart(i);
                //某一个邮件体也有可能是由多个邮件体组成的复杂体
                String disp = bodyPart.getDisposition();
                if (disp != null && (disp.equalsIgnoreCase(Part.ATTACHMENT) || disp.equalsIgnoreCase(Part.INLINE))) {
                    // 设置文件最后路径
                    attchPath.append(destDir + decodeText(bodyPart.getFileName())).append(",");
                } else if (bodyPart.isMimeType("multipart/*")) {
                    saveAttachmentForSend(bodyPart, destDir);
                } else {
                    String contentType = bodyPart.getContentType();
                    if (contentType.indexOf("name") != -1 || contentType.indexOf("application") != -1) {
                        // 设置文件最后路径
                        attchPath.append(destDir + decodeText(bodyPart.getFileName())).append(",");
                    }
                }
            }
        } else if (part.isMimeType("message/rfc822")) {
            saveAttachmentForSend((Part) part.getContent(), destDir);
        }
        // 判断是否有文件路径生成
        if (attchPath.length() > 0) {
            return attchPath.toString();
        }

        return StringUtils.EMPTY;
    }

    static class MyAuthenricator extends Authenticator {
        private String userName;
        private String password;

        public MyAuthenricator(String userName, String password) {
            this.userName = userName;
            this.password = password;
        }

        @Override
        protected PasswordAuthentication getPasswordAuthentication() {
            return new PasswordAuthentication(userName, password);
        }
    }
}