JavaMail判断新邮件

public class Pop3ReceivedDateTerm extends SearchTerm {

	private static final long serialVersionUID = 4363009965326553239L;

	private int comparison;

	private Date date;

	public Pop3ReceivedDateTerm(int comparison, Date date) {
		this.comparison = comparison;
		this.date = date;
	}

	@Override
	public boolean match(Message message) {
		if ((message instanceof POP3Message) == false) {
			throw new IllegalStateException("The message is not POP3Message!");
		}
		if (this.date == null) {
			throw new IllegalArgumentException("The receivedDate could not be null!");
		}

		Date receivedDate = MailUtil.getPop3ReceivedDate((POP3Message) message);
		if (receivedDate == null) {
			return false;
		} else if (ComparisonTerm.EQ == this.comparison) {
			return this.date.equals(receivedDate);
		} else if (ComparisonTerm.GE == this.comparison) {
			return this.date.before(receivedDate) || this.date.equals(receivedDate);
		} else if (ComparisonTerm.GT == this.comparison) {
			return this.date.before(receivedDate);
		} else if (ComparisonTerm.LE == this.comparison) {
			return this.date.after(receivedDate) || this.date.equals(receivedDate);
		} else if (ComparisonTerm.LT == this.comparison) {
			return this.date.after(receivedDate);
		} else if (ComparisonTerm.NE == this.comparison) {
			return !this.date.equals(receivedDate);
		}
		return false;
	}

}

public static Date getPop3ReceivedDate(POP3Message message){
		try {
			String[] strs = message.getHeader("Date");			
			if(strs==null || strs.length != 1){
				return null;
			}
			
			String date = strs[0];
			DateFormat dateFormat = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss Z",Locale.US);
			return dateFormat.parse(date);
		} catch (Exception e) {
			return null;
		}
	}