利用Javamail写eml文件
原文：http://www.java-cn.com/club/html/72/n-572.html
import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.util.Date;import java.util.Properties;import java.util.Vector;import javax.activation.DataHandler;import javax.activation.FileDataSource;import javax.mail.Address;import javax.mail.Message;import javax.mail.MessagingException;import javax.mail.Multipart;import javax.mail.Session;import javax.mail.internet.InternetAddress;import javax.mail.internet.MimeBodyPart;import javax.mail.internet.MimeMessage;import javax.mail.internet.MimeMultipart;import javax.mail.internet.MimeUtility;import org.springframework.util.StringUtils;/** * 利用Javamail写eml文件 */public class EmailFileWriter {// 定义发件人、收件人、SMTP服务器、用户名、密码、主题、内容等private String displayName;private String from;private String to;private String cc;private String bcc;private String server;private String subject;private String content;/** * 用于保存发送附件的文件名的集合（<code>new String[]{文件名,显示名称}</code>） */private Vector<String[]> attachList = new Vector<String[]>();private String contentType = "text/html";private String charset = "utf-8";private int port = 25;private Date sentDate;public EmailFileWriter() {}/** * 用于保存发送附件的文件名的集合（<code>new String[]{文件名,显示名称}</code>） */public void addFile(String[] filename) {attachList.add(filename);}public String getContentType() {return contentType;}public void setContentType(String contentType) {this.contentType = contentType;}public String getCharset() {return charset;}public void setCharset(String charset) {this.charset = charset;}/** * 设置SMTP服务器地址 */public void setServer(String smtpServer) {this.server = smtpServer;}/** * 设置发件人的地址 */public void setFrom(String from) {this.from = from;}/** * 设置显示的名称 */public void setDisplayName(String displayName) {this.displayName = displayName;}/** * 设置接收者 */public void setTo(String to) {this.to = to;}public String getCc() {return cc;}public void setCc(String cc) {this.cc = cc;}public String getBcc() {return bcc;}public void setBcc(String bcc) {this.bcc = bcc;}/** * 设置主题 */public void setSubject(String subject) {this.subject = subject;}/** * 设置主体内容 */public void setContent(String content) {this.content = content;}public Date getSentDate() {return sentDate;}public void setSentDate(Date sentDate) {this.sentDate = sentDate;}public int getPort() {return port;}public void setPort(int port) {this.port = port;}/** * 将email写至文件 * * @throws IOException * @throws FileNotFoundException * @throws MessagingException */public void writeTo(String filename) throws FileNotFoundException,IOException, MessagingException {Properties props = System.getProperties();props.put("mail.smtp.host", server);props.put("mail.smtp.port", port);props.put("mail.smtp.auth", "false");Session session = Session.getDefaultInstance(props, null);session.setDebug(false);Message msg = new MimeMessage(session);Address from_address = new InternetAddress(from, displayName);msg.setFrom(from_address);InternetAddress[] addressTo = { new InternetAddress(to) };msg.setRecipients(Message.RecipientType.TO, addressTo);if (StringUtils.hasLength(cc)) {InternetAddress[] addressCc = { new InternetAddress(cc) };msg.setRecipients(Message.RecipientType.CC, addressCc);}if (StringUtils.hasLength(bcc)) {InternetAddress[] addressBcc = { new InternetAddress(bcc) };msg.setRecipients(Message.RecipientType.BCC, addressBcc);}msg.setSubject(subject);Multipart mp = new MimeMultipart();MimeBodyPart mbp = new MimeBodyPart();mbp.setContent(content.toString(), getContentType() + "; charset="+ getCharset());mp.addBodyPart(mbp);if (!attachList.isEmpty()) {// 有附件for (String[] file : attachList) {mbp = new MimeBodyPart();FileDataSource fds = new FileDataSource(file[0]); // 得到数据源mbp.setDataHandler(new DataHandler(fds)); // 得到附件本身并至入BodyPartString dspName = file.length < 2 ? fds.getName() : file[1];mbp.setFileName(MimeUtility.encodeText(dspName, getCharset(),"B")); // 得到文件名同样至入BodyPartmp.addBodyPart(mbp);}attachList.removeAllElements();}msg.setContent(mp); // Multipart加入到信件msg.setSentDate(getSentDate()); // 设置信件头的发送日期msg.saveChanges();// 写至文件msg.writeTo(new FileOutputStream(new File(filename)));}}