skinutils.java

这是学习Java必须读懂两套源代码

        Cookie cookie = getCookie(request,name);
        if(cookie != null) {
            return cookie.getValue();
        }
        return null;
    }

    /**
     * Formats the unfiltered body of a message to make it appear in the "quote
     * original" format. This is simply the body of the message with the
     * delimiter appended to the beginning of each line. The delimiter
     * is most often "> " by convention. A desired length for each line in the
     * returned String can be specified to aid in formatting.<p>
     *
     * This method uses message.getUnfilteredBody() in order to get the body of
     * the message. This usually yields better results for the formatting
     * required by this method. However, it also has the potential of being
     * a security risk if malicious HTML code is embedded in the body. Therefore,
     * you should always filter HTML from the result of this method before
     * showing it in an environment where HTML is interpreted. If you are
     * showing the results of this method in an HTML &lt;textarea&gt;, there is
     * no need to worry about malicious HTML.
     *
     * @param message the message to quote.
     * @param delimiter a String that will start each line of the quoted
     *      message. For example, "> ";
     * @param lineLength the desired length of each line in the quoted message.
     * @return the unfiltered body of the message in the "quote original" format.
     */
    public static String quoteOriginal(String body, String delimiter,
            int lineLength)
    {
        if (body == null || body.length() == 0) {
            return "";
        }
        int length = body.length();
        //Create a StringBuffer to hold the quoted body; approximate size.
        StringBuffer buf = new StringBuffer(body.length());
        //i maintains the current position in the String.
        for (int i=0; i<length; ) {
            String partialString =
                StringUtils.chopAtWord(
                    body.substring(i),
                    lineLength
                );
            //System.out.println("--" + partialString);
            i += partialString.length()+1;
            buf.append(delimiter).append(partialString.trim()).append("\\n");
        }
        return buf.toString();
    }

    /**
     * Returns a String describing the amount of time between now (current
     * system time) and the passed in date time. Example output is "5 hours
     * ago" or "Yesterday at 3:30 pm"
     *
     * @param date the Date to compare the current time with.
     * @return a description of the difference in time, ie: "5 hours ago"
     *      or "Yesterday at 3:30pm"
     */
    public static String dateToText( Date date ) {
        if( date == null ) {
            return "";
        }

        long delta = System.currentTimeMillis() - date.getTime();

        // within the last hour
        if( (delta / HOUR) < 1 ) {
            long minutes = (delta/MINUTE);
            if( minutes == 0 ) {
                return "Less than 1 min ago";
            }
            else if( minutes == 1 ) {
                return "1 minute ago";
            }
            else {
                return ( minutes + " minutes ago" );
            }
        }

        // sometime today
        if( (delta / DAY) < 1 ) {
            long hours = (delta/HOUR);
            if( hours <= 1 ) {
                return "1 hour ago";
            }
            else {
                return ( hours + " hours ago" );
            }
        }

        // within the last week
        if( (delta / WEEK) < 1 ) {
            double days = ((double)delta/(double)DAY);
            if( days <= 1.0 ) {
                return yesterdayFormatter.format(date);
            }
            else {
                return dateFormatter.format(date);
            }
        }

        // before a week ago
        else {
            return dateFormatter.format(date);
        }
    }

    /**
     * Returns true if the user is a system administrator.
     *
     * @param authToken the authentication token of the user
     * @return true if the user is a system administrator, false otherwise.
     */
    public static boolean isSystemAdmin( Authorization authToken ) {
        ForumFactory forumFactory = ForumFactory.getInstance(authToken);
        ForumPermissions permissions = forumFactory.getPermissions(authToken);
        return permissions.get(ForumPermissions.SYSTEM_ADMIN);
    }

    /**
     * Returns true if the user is a forum adminstrator of any forum in the
     * system. For example, if there are 3 forums in the system and the user
     * is an adminstrator of any one or more of them, this method will return
     * true.<p>
     *
     * Use the method <code>isForumAdmin( Authorization, Forum)</code> to
     * check an individual forum for administrator status.)
     *
     * @param authToken the authentication token of the user
     * @return true if the user is a forum administrator of any forum in the system.
     * @see SkinUtils#isForumAdmin(Authorization, Forum)
     */
    public static boolean isForumAdmin( Authorization authToken ) {
        ForumFactory forumFactory = ForumFactory.getInstance(authToken);
        Iterator forumIterator = forumFactory.forums();
        if( !forumIterator.hasNext() ) {
            return false;
        }
        while( forumIterator.hasNext() ) {
            Forum forum = (Forum)forumIterator.next();
            if( forum.hasPermission(ForumPermissions.FORUM_ADMIN) ) {
                return true;
            }
        }
        return false;
    }

    /**
     * Returns true if the user is a forum moderator of any forum in the
     * system. For example, if there are 3 forums in the system and the user
     * is a moderator of any one or more of them, this method will return
     * true.<p>
     *
     * Use the method <code>isForumModerator( Authorization, Forum)</code> to
     * check an individual forum for moderator status.)
     *
     * @param authToken the authentication token of the user
     * @return true if the user is a forum moderator of any forum in the system.
     * @see SkinUtils#isForumModerator(Authorization, Forum)
     */
    public static boolean isForumModerator( Authorization authToken ) {
        ForumFactory forumFactory = ForumFactory.getInstance(authToken);
        Iterator forumIterator = forumFactory.forums();
        if( !forumIterator.hasNext() ) {
            return false;
        }
        while( forumIterator.hasNext() ) {
            Forum forum = (Forum)forumIterator.next();
            if( forum.hasPermission(ForumPermissions.MODERATOR) ) {
                return true;
            }
        }
        return false;
    }

    /**
     * Returns true if the user is a forum adminstrator of the given forum.
     *
     * @param authToken the authentication token of the user
     * @param forum the forum to check administrator status on.
     * @return true if the user is a forum administrator of the given forum.
     */
    public static boolean isForumAdmin( Authorization authToken, Forum forum ) {
        return( forum.hasPermission(ForumPermissions.FORUM_ADMIN) );
    }
    /**
     * Returns true if the user is a forum moderator of the given forum.
     *
     * @param authToken the authentication token of the user
     * @param forum the forum to check moderator status on.
     * @return true if the user is a forum moderator of the given forum.
     */
    public static boolean isForumModerator( Authorization authToken, Forum forum ) {
        return( forum.hasPermission(ForumPermissions.MODERATOR) );
    }

    /**
     * Returns true if the user is a group administrator of any group in the
     * system. For example, if there are 3 groups in the system and the user
     * is an adminstrator of any one or more of them, this method will return
     * true.<p>
     *
     * Use the method <code>isGroupAdmin( Authorization, Group)</code> to check
     * an individual group for administrator status.)
     *
     * @see SkinUtils#isGroupAdmin(Authorization, Group)
     */
    public static boolean isGroupAdmin( Authorization authToken ) {
        ForumFactory forumFactory = ForumFactory.getInstance(authToken);
        ProfileManager manager = forumFactory.getProfileManager();
        Iterator groupIterator = manager.groups();
        if( !groupIterator.hasNext() ) {
            return false;
        }
        while( groupIterator.hasNext() ) {
            Group group = (Group)groupIterator.next();
            if( group.hasPermission(ForumPermissions.GROUP_ADMIN) ) {
                return true;
            }
        }
        return false;
    }

    /**
     * Returns true if the user is a group administrator of the given group.
     *
     * @param authToken the authentication token of the user
     * @param group the group to check administrator status on.
     * @return true if the user is a group administrator of the given group.
     */
    public static boolean isGroupAdmin( Authorization authToken, Group group ) {
        return( group.hasPermission(ForumPermissions.GROUP_ADMIN) );
    }

    /**
     * Builds a cookie string containing a username and password.<p>
     *
     * Note: with open source this is not really secure, but it prevents users
     * from snooping the cookie file of others and by changing the XOR mask and
     * character offsets, you can easily tweak results.
     *
     * @param username The username.
     * @param password The password.
     * @return String encoding the input parameters, an empty string if one of
     *      the arguments equals <code>null</code>.
     */
    private static String encodePasswordCookie (String username, String password)
    {
        StringBuffer buf = new StringBuffer();
        if (username != null && password != null) {
            byte[] bytes = (username + ENCODE_DELIMETER + password).getBytes();
            int    b;

            for (int n = 0; n < bytes.length; n++) {
                b = bytes[n] ^ (ENCODE_XORMASK + n);
                buf.append((char)(ENCODE_CHAR_OFFSET1 + (b & 0x0F)));
                buf.append((char)(ENCODE_CHAR_OFFSET2 + ((b >> 4) & 0x0F)));
            }
        }
        return buf.toString();
    }

    /**
     * Unrafels a cookie string containing a username and password.
     * @param value The cookie value.
     * @return String[] containing the username at index 0 and the password at
     *      index 1, or <code>{ null, null }</code> if cookieVal equals
     *      <code>null</code> or the empty string.
     */
    private static String[] decodePasswordCookie( String cookieVal ) {

        // check that the cookie value isn't null or zero-length
        if( cookieVal == null || cookieVal.length() <= 0 ) {
            return null;
        }

        // unrafel the cookie value
        char[] chars = cookieVal.toCharArray();
        byte[] bytes = new byte[chars.length / 2];
        int b;
        for (int n = 0, m = 0; n < bytes.length; n++) {
            b = chars[m++] - ENCODE_CHAR_OFFSET1;
            b |= (chars[m++] - ENCODE_CHAR_OFFSET2) << 4;
            bytes[n] = (byte)(b ^ (ENCODE_XORMASK + n));
        }
        cookieVal = new String(bytes);
        int	pos = cookieVal.indexOf(ENCODE_DELIMETER);
        String username = (pos < 0) ? "" : cookieVal.substring(0, pos);
        String password = (pos < 0) ? "" : cookieVal.substring(pos + 1);

        return new String[] { username, password };
    }

    /**
     *  test method for this class
     */
     /*
    public static void main( String args[] ) {
        Calendar cal = Calendar.getInstance();
        System.out.println( "now:\t" + dateToText(cal.getTime()) );
        for( int i=0; i<122; i++ ) {
            cal.setTime( new Date(cal.getTime().getTime() - (30*MINUTE) ) );
            System.out.println( (i+1) + " min ago:\t" + dateToText(cal.getTime()) + "\t" + cal.getTime() );
        }
    }
    */

}