MailHandler.java 文件源码

/**
 * Sets the attachment <tt>Formatter</tt> object for this handler.
 * The number of formatters determines the number of attachments per
 * email.  This method should be the first attachment method called.
 * To remove all attachments, call this method with empty array.
 * @param formatters a non null array of formatters.
 * @throws SecurityException  if a security manager exists and the
 * caller does not have <tt>LoggingPermission("control")</tt>.
 * @throws NullPointerException if the given array or any array index is
 * <tt>null</tt>.
 * @throws IllegalStateException if called from inside a push.
 */
public final void setAttachmentFormatters(Formatter... formatters) {
    checkAccess();
    if (formatters.length == 0) { //Null check and length check.
        formatters = emptyFormatterArray();
    } else {
        formatters = copyOf(formatters,
                formatters.length, Formatter[].class);
        for (int i = 0; i < formatters.length; ++i) {
            if (formatters[i] == null) {
                throw new NullPointerException(atIndexMsg(i));
            }
        }
    }

    synchronized (this) {
        if (isWriting) {
            throw new IllegalStateException();
        }

        this.attachmentFormatters = formatters;
        this.fixUpAttachmentFilters();
        this.fixUpAttachmentNames();
    }
}