quarter.java

用于制作报表的中间件控件,纯java编写,还附带有数据库操作的源代码

    public void peg(Calendar calendar) {
        this.firstMillisecond = getFirstMillisecond(calendar);
        this.lastMillisecond = getLastMillisecond(calendar);
    }

    /**
     * Returns the quarter preceding this one.
     *
     * @return The quarter preceding this one (or <code>null</code> if this is 
     *     Q1 1900).
     */
    public RegularTimePeriod previous() {
        Quarter result;
        if (this.quarter > FIRST_QUARTER) {
            result = new Quarter(this.quarter - 1, this.year);
        }
        else {
            if (this.year > 1900) {
                result = new Quarter(LAST_QUARTER, this.year - 1);
            }
            else {
                result = null;
            }
        }
        return result;
    }

    /**
     * Returns the quarter following this one.
     *
     * @return The quarter following this one (or null if this is Q4 9999).
     */
    public RegularTimePeriod next() {
        Quarter result;
        if (this.quarter < LAST_QUARTER) {
            result = new Quarter(this.quarter + 1, this.year);
        }
        else {
            if (this.year < 9999) {
                result = new Quarter(FIRST_QUARTER, this.year + 1);
            }
            else {
                result = null;
            }
        }
        return result;
    }

    /**
     * Returns a serial index number for the quarter.
     *
     * @return The serial index number.
     */
    public long getSerialIndex() {
        return this.year * 4L + this.quarter;
    }

    /**
     * Tests the equality of this Quarter object to an arbitrary object.
     * Returns <code>true</code> if the target is a Quarter instance 
     * representing the same quarter as this object.  In all other cases, 
     * returns <code>false</code>.
     *
     * @param obj  the object (<code>null</code> permitted).
     *
     * @return <code>true</code> if quarter and year of this and the object are
     *         the same.
     */
    public boolean equals(Object obj) {

        if (obj != null) {
            if (obj instanceof Quarter) {
                Quarter target = (Quarter) obj;
                return (this.quarter == target.getQuarter()
                        && (this.year == target.getYearValue()));
            }
            else {
                return false;
            }
        }
        else {
            return false;
        }

    }

    /**
     * Returns a hash code for this object instance.  The approach described by
     * Joshua Bloch in "Effective Java" has been used here:
     * <p>
     * <code>http://developer.java.sun.com/developer/Books/effectivejava
     * /Chapter3.pdf</code>
     * 
     * @return A hash code.
     */
    public int hashCode() {
        int result = 17;
        result = 37 * result + this.quarter;
        result = 37 * result + this.year;
        return result;
    }

    /**
     * Returns an integer indicating the order of this Quarter object relative
     * to the specified object:
     *
     * negative == before, zero == same, positive == after.
     *
     * @param o1  the object to compare
     *
     * @return negative == before, zero == same, positive == after.
     */
    public int compareTo(Object o1) {

        int result;

        // CASE 1 : Comparing to another Quarter object
        // --------------------------------------------
        if (o1 instanceof Quarter) {
            Quarter q = (Quarter) o1;
            result = this.year - q.getYearValue();
            if (result == 0) {
                result = this.quarter - q.getQuarter();
            }
        }

        // CASE 2 : Comparing to another TimePeriod object
        // -----------------------------------------------
        else if (o1 instanceof RegularTimePeriod) {
            // more difficult case - evaluate later...
            result = 0;
        }

        // CASE 3 : Comparing to a non-TimePeriod object
        // ---------------------------------------------
        else {
            // consider time periods to be ordered after general objects
            result = 1;
        }

        return result;

    }

    /**
     * Returns a string representing the quarter (e.g. "Q1/2002").
     *
     * @return A string representing the quarter.
     */
    public String toString() {
        return "Q" + this.quarter + "/" + this.year;
    }

    /**
     * Returns the first millisecond in the Quarter, evaluated using the
     * supplied calendar (which determines the time zone).
     *
     * @param calendar  the calendar (<code>null</code> not permitted).
     *
     * @return The first millisecond in the Quarter.
     *
     * @throws NullPointerException if <code>calendar</code> is 
     *     <code>null</code>.
     */
    public long getFirstMillisecond(Calendar calendar) {
        int month = Quarter.FIRST_MONTH_IN_QUARTER[this.quarter];
        calendar.set(this.year, month - 1, 1, 0, 0, 0);
        calendar.set(Calendar.MILLISECOND, 0);
        // in the following line, we'd rather call calendar.getTimeInMillis()
        // to avoid object creation, but that isn't supported in Java 1.3.1
        return calendar.getTime().getTime();
    }

    /**
     * Returns the last millisecond of the Quarter, evaluated using the
     * supplied calendar (which determines the time zone).
     *
     * @param calendar  the calendar (<code>null</code> not permitted).
     *
     * @return The last millisecond of the Quarter.
     *
     * @throws NullPointerException if <code>calendar</code> is 
     *     <code>null</code>.
     */
    public long getLastMillisecond(Calendar calendar) {
        int month = Quarter.LAST_MONTH_IN_QUARTER[this.quarter];
        int eom = SerialDate.lastDayOfMonth(month, this.year);
        calendar.set(this.year, month - 1, eom, 23, 59, 59);
        calendar.set(Calendar.MILLISECOND, 999);
        // in the following line, we'd rather call calendar.getTimeInMillis()
        // to avoid object creation, but that isn't supported in Java 1.3.1
        return calendar.getTime().getTime();
    }

    /**
     * Parses the string argument as a quarter.
     * <P>
     * This method should accept the following formats: "YYYY-QN" and "QN-YYYY",
     * where the "-" can be a space, a forward-slash (/), comma or a dash (-).
     * @param s A string representing the quarter.
     *
     * @return The quarter.
     */
    public static Quarter parseQuarter(String s) {

        // find the Q and the integer following it (remove both from the
        // string)...
        int i = s.indexOf("Q");
        if (i == -1) {
            throw new TimePeriodFormatException("Missing Q.");
        }

        if (i == s.length() - 1) {
            throw new TimePeriodFormatException("Q found at end of string.");
        }

        String qstr = s.substring(i + 1, i + 2);
        int quarter = Integer.parseInt(qstr);
        String remaining = s.substring(0, i) + s.substring(i + 2, s.length());

        // replace any / , or - with a space
        remaining = remaining.replace('/', ' ');
        remaining = remaining.replace(',', ' ');
        remaining = remaining.replace('-', ' ');

        // parse the string...
        Year year = Year.parseYear(remaining.trim());
        Quarter result = new Quarter(quarter, year);
        return result;

    }

}