/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package java.sql;

import java.util.StringTokenizer;

/**

 * <P>A thin wrapper around <code>java.util.Date</code> that allows

 * the JDBC API to identify this as an SQL <code>TIMESTAMP</code> value.

 * It adds the ability

 * to hold the SQL <code>TIMESTAMP</code> fractional seconds value, by allowing

 * the specification of fractional seconds to a precision of nanoseconds.

 * A Timestamp also provides formatting and

 * parsing operations to support the JDBC escape syntax for timestamp values.

 *

 * <p>The precision of a Timestamp object is calculated to be either:

 * <ul>

 * <li><code>19 </code>, which is the number of characters in yyyy-mm-dd hh:mm:ss

 * <li> <code> 20 + s </code>, which is the number

 * of characters in the yyyy-mm-dd hh:mm:ss.[fff...] and <code>s</code> represents  the scale of the given Timestamp,

 * its fractional seconds precision.

 *</ul>

 *

 * <P><B>Note:</B> This type is a composite of a <code>java.util.Date</code> and a

 * separate nanoseconds value. Only integral seconds are stored in the

 * <code>java.util.Date</code> component. The fractional seconds - the nanos - are

 * separate.  The <code>Timestamp.equals(Object)</code> method never returns

 * <code>true</code> when passed an object

 * that isn't an instance of <code>java.sql.Timestamp</code>,

 * because the nanos component of a date is unknown.

 * As a result, the <code>Timestamp.equals(Object)</code>

 * method is not symmetric with respect to the

 * <code>java.util.Date.equals(Object)</code>

 * method.  Also, the <code>hashcode</code> method uses the underlying

 * <code>java.util.Date</code>

 * implementation and therefore does not include nanos in its computation.

 * <P>

 * Due to the differences between the <code>Timestamp</code> class

 * and the <code>java.util.Date</code>

 * class mentioned above, it is recommended that code not view

 * <code>Timestamp</code> values generically as an instance of

 * <code>java.util.Date</code>.  The

 * inheritance relationship between <code>Timestamp</code>

 * and <code>java.util.Date</code> really

 * denotes implementation inheritance, and not type inheritance.

 */

public class Timestamp extends java.util.Date {

    /**

     * Constructs a <code>Timestamp</code> object initialized

     * with the given values.

     *

     * @param year the year minus 1900

     * @param month 0 to 11

     * @param date 1 to 31

     * @param hour 0 to 23

     * @param minute 0 to 59

     * @param second 0 to 59

     * @param nano 0 to 999,999,999

     * @deprecated instead use the constructor <code>Timestamp(long millis)</code>

     * @exception IllegalArgumentException if the nano argument is out of bounds

     */

    @Deprecated

    public Timestamp(int year, int month, int date,

                     int hour, int minute, int second, int nano) {

        super(year, month, date, hour, minute, second);

        if (nano > 999999999 || nano < 0) {

            throw new IllegalArgumentException("nanos > 999999999 or < 0");

        }

        nanos = nano;

    }

    /**

     * Constructs a <code>Timestamp</code> object

     * using a milliseconds time value. The

     * integral seconds are stored in the underlying date value; the

     * fractional seconds are stored in the <code>nanos</code> field of

     * the <code>Timestamp</code> object.

     *

     * @param time milliseconds since January 1, 1970, 00:00:00 GMT.

     *        A negative number is the number of milliseconds before

     *         January 1, 1970, 00:00:00 GMT.

     * @see java.util.Calendar

     */

    public Timestamp(long time) {

        super((time/1000)*1000);

        nanos = (int)((time%1000) * 1000000);

        if (nanos < 0) {

            nanos = 1000000000 + nanos;

            super.setTime(((time/1000)-1)*1000);

        }

    }

    /**

     * Sets this <code>Timestamp</code> object to represent a point in time that is

     * <tt>time</tt> milliseconds after January 1, 1970 00:00:00 GMT.

     *

     * @param time   the number of milliseconds.

     * @see #getTime

     * @see #Timestamp(long time)

     * @see java.util.Calendar

     */

    public void setTime(long time) {

        super.setTime((time/1000)*1000);

        nanos = (int)((time%1000) * 1000000);

        if (nanos < 0) {

            nanos = 1000000000 + nanos;

            super.setTime(((time/1000)-1)*1000);

        }

    }

    /**

     * Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT

     * represented by this <code>Timestamp</code> object.

     *

     * @return  the number of milliseconds since January 1, 1970, 00:00:00 GMT

     *          represented by this date.

     * @see #setTime

     */

    public long getTime() {

        long time = super.getTime();

        return (time + (nanos / 1000000));

    }

    /**

     * @serial

     */

    private int nanos;

    /**

     * Converts a <code>String</code> object in JDBC timestamp escape format to a

     * <code>Timestamp</code> value.

     *

     * @param s timestamp in format <code>yyyy-[m]m-[d]d hh:mm:ss[.f...]</code>.  The

     * fractional seconds may be omitted. The leading zero for <code>mm</code>

     * and <code>dd</code> may also be omitted.

     *

     * @return corresponding <code>Timestamp</code> value

     * @exception java.lang.IllegalArgumentException if the given argument

     * does not have the format <code>yyyy-[m]m-[d]d hh:mm:ss[.f...]</code>

     */

    public static Timestamp valueOf(String s) {

        final int YEAR_LENGTH = 4;

        final int MONTH_LENGTH = 2;

        final int DAY_LENGTH = 2;

        final int MAX_MONTH = 12;

        final int MAX_DAY = 31;

        String date_s;

        String time_s;

        String nanos_s;

        int year = 0;

        int month = 0;

        int day = 0;

        int hour;

        int minute;

        int second;

        int a_nanos = 0;

        int firstDash;

        int secondDash;

        int dividingSpace;

        int firstColon = 0;

        int secondColon = 0;

        int period = 0;

        String formatError = "Timestamp format must be yyyy-mm-dd hh:mm:ss[.fffffffff]";

        String zeros = "000000000";

        String delimiterDate = "-";

        String delimiterTime = ":";

        if (s == null) throw new java.lang.IllegalArgumentException("null string");

        // Split the string into date and time components

        s = s.trim();

        dividingSpace = s.indexOf(' ');

        if (dividingSpace > 0) {

            date_s = s.substring(0,dividingSpace);

            time_s = s.substring(dividingSpace+1);

        } else {

            throw new java.lang.IllegalArgumentException(formatError);

        }

        // Parse the date

        firstDash = date_s.indexOf('-');

        secondDash = date_s.indexOf('-', firstDash+1);

        // Parse the time

        if (time_s == null)

            throw new java.lang.IllegalArgumentException(formatError);

        firstColon = time_s.indexOf(':');

        secondColon = time_s.indexOf(':', firstColon+1);

        period = time_s.indexOf('.', secondColon+1);

        // Convert the date

        boolean parsedDate = false;

        if ((firstDash > 0) && (secondDash > 0) && (secondDash < date_s.length() - 1)) {

            String yyyy = date_s.substring(0, firstDash);

            String mm = date_s.substring(firstDash + 1, secondDash);

            String dd = date_s.substring(secondDash + 1);

            if (yyyy.length() == YEAR_LENGTH &&

                    (mm.length() >= 1 && mm.length() <= MONTH_LENGTH) &&

                    (dd.length() >= 1 && dd.length() <= DAY_LENGTH)) {

                 year = Integer.parseInt(yyyy);

                 month = Integer.parseInt(mm);

                 day = Integer.parseInt(dd);

                if ((month >= 1 && month <= MAX_MONTH) && (day >= 1 && day <= MAX_DAY)) {

                    parsedDate = true;

                }

            }

        }

        if (! parsedDate) {

            throw new java.lang.IllegalArgumentException(formatError);

        }

        // Convert the time; default missing nanos

        if ((firstColon > 0) & (secondColon > 0) &

            (secondColon < time_s.length()-1)) {

            hour = Integer.parseInt(time_s.substring(0, firstColon));

            minute =

                Integer.parseInt(time_s.substring(firstColon+1, secondColon));

            if ((period > 0) & (period < time_s.length()-1)) {

                second =

                    Integer.parseInt(time_s.substring(secondColon+1, period));

                nanos_s = time_s.substring(period+1);

                if (nanos_s.length() > 9)

                    throw new java.lang.IllegalArgumentException(formatError);

                if (!Character.isDigit(nanos_s.charAt(0)))

                    throw new java.lang.IllegalArgumentException(formatError);

                nanos_s = nanos_s + zeros.substring(0,9-nanos_s.length());

                a_nanos = Integer.parseInt(nanos_s);

            } else if (period > 0) {

                throw new java.lang.IllegalArgumentException(formatError);

            } else {

                second = Integer.parseInt(time_s.substring(secondColon+1));

            }

        } else {

            throw new java.lang.IllegalArgumentException(formatError);

        }

        return new Timestamp(year - 1900, month - 1, day, hour, minute, second, a_nanos);

    }

    /**

     * Formats a timestamp in JDBC timestamp escape format.

     *         <code>yyyy-mm-dd hh:mm:ss.fffffffff</code>,

     * where <code>ffffffffff</code> indicates nanoseconds.

     * <P>

     * @return a <code>String</code> object in

     *           <code>yyyy-mm-dd hh:mm:ss.fffffffff</code> format

     */

    public String toString () {

        int year = super.getYear() + 1900;

        int month = super.getMonth() + 1;

        int day = super.getDate();

        int hour = super.getHours();

        int minute = super.getMinutes();

        int second = super.getSeconds();

        String yearString;

        String monthString;

        String dayString;

        String hourString;

        String minuteString;

        String secondString;

        String nanosString;

        String zeros = "000000000";

        String yearZeros = "0000";

        StringBuffer timestampBuf;

        if (year < 1000) {

            // Add leading zeros

            yearString = "" + year;

            yearString = yearZeros.substring(0, (4-yearString.length())) +

                yearString;

        } else {

            yearString = "" + year;

        }

        if (month < 10) {

            monthString = "0" + month;

        } else {

            monthString = Integer.toString(month);

        }

        if (day < 10) {

            dayString = "0" + day;

        } else {

            dayString = Integer.toString(day);

        }

        if (hour < 10) {

            hourString = "0" + hour;

        } else {

            hourString = Integer.toString(hour);

        }

        if (minute < 10) {

            minuteString = "0" + minute;

        } else {

            minuteString = Integer.toString(minute);

        }

        if (second < 10) {

            secondString = "0" + second;

        } else {

            secondString = Integer.toString(second);

        }

        if (nanos == 0) {

            nanosString = "0";

        } else {

            nanosString = Integer.toString(nanos);

            // Add leading zeros

            nanosString = zeros.substring(0, (9-nanosString.length())) +

                nanosString;

            // Truncate trailing zeros

            char[] nanosChar = new char[nanosString.length()];

            nanosString.getChars(0, nanosString.length(), nanosChar, 0);

            int truncIndex = 8;

            while (nanosChar[truncIndex] == '0') {

                truncIndex--;

            }

            nanosString = new String(nanosChar, 0, truncIndex + 1);

        }

        // do a string buffer here instead.

        timestampBuf = new StringBuffer(20+nanosString.length());

        timestampBuf.append(yearString);

        timestampBuf.append("-");

        timestampBuf.append(monthString);

        timestampBuf.append("-");

        timestampBuf.append(dayString);

        timestampBuf.append(" ");

        timestampBuf.append(hourString);

        timestampBuf.append(":");

        timestampBuf.append(minuteString);

        timestampBuf.append(":");

        timestampBuf.append(secondString);

        timestampBuf.append(".");

        timestampBuf.append(nanosString);

        return (timestampBuf.toString());

    }

    /**

     * Gets this <code>Timestamp</code> object's <code>nanos</code> value.

     *

     * @return this <code>Timestamp</code> object's fractional seconds component

     * @see #setNanos

     */

    public int getNanos() {

        return nanos;

    }

    /**

     * Sets this <code>Timestamp</code> object's <code>nanos</code> field

     * to the given value.

     *

     * @param n the new fractional seconds component

     * @exception java.lang.IllegalArgumentException if the given argument

     *            is greater than 999999999 or less than 0

     * @see #getNanos

     */

    public void setNanos(int n) {

        if (n > 999999999 || n < 0) {

            throw new IllegalArgumentException("nanos > 999999999 or < 0");

        }

        nanos = n;

    }

    /**

     * Tests to see if this <code>Timestamp</code> object is

     * equal to the given <code>Timestamp</code> object.

     *

     * @param ts the <code>Timestamp</code> value to compare with

     * @return <code>true</code> if the given <code>Timestamp</code>

     *         object is equal to this <code>Timestamp</code> object;

     *         <code>false</code> otherwise

     */

    public boolean equals(Timestamp ts) {

        if (super.equals(ts)) {

            if  (nanos == ts.nanos) {

                return true;

            } else {

                return false;

            }

        } else {

            return false;

        }

    }

    /**

     * Tests to see if this <code>Timestamp</code> object is

     * equal to the given object.

     *

     * This version of the method <code>equals</code> has been added

     * to fix the incorrect

     * signature of <code>Timestamp.equals(Timestamp)</code> and to preserve backward

     * compatibility with existing class files.

     *

     * Note: This method is not symmetric with respect to the

     * <code>equals(Object)</code> method in the base class.

     *

     * @param ts the <code>Object</code> value to compare with

     * @return <code>true</code> if the given <code>Object</code> is an instance

     *         of a <code>Timestamp</code> that

     *         is equal to this <code>Timestamp</code> object;

     *         <code>false</code> otherwise

     */

    public boolean equals(java.lang.Object ts) {

      if (ts instanceof Timestamp) {

        return this.equals((Timestamp)ts);

      } else {

        return false;

      }

    }

    /**

     * Indicates whether this <code>Timestamp</code> object is

     * earlier than the given <code>Timestamp</code> object.

     *

     * @param ts the <code>Timestamp</code> value to compare with

     * @return <code>true</code> if this <code>Timestamp</code> object is earlier;

     *        <code>false</code> otherwise

     */

    public boolean before(Timestamp ts) {

        return compareTo(ts) < 0;

    }

    /**

     * Indicates whether this <code>Timestamp</code> object is

     * later than the given <code>Timestamp</code> object.

     *

     * @param ts the <code>Timestamp</code> value to compare with

     * @return <code>true</code> if this <code>Timestamp</code> object is later;

     *        <code>false</code> otherwise

     */

    public boolean after(Timestamp ts) {

        return compareTo(ts) > 0;

    }

    /**

     * Compares this <code>Timestamp</code> object to the given

     * <code>Timestamp</code> object.

     *

     * @param   ts   the <code>Timestamp</code> object to be compared to

     *                this <code>Timestamp</code> object

     * @return  the value <code>0</code> if the two <code>Timestamp</code>

     *          objects are equal; a value less than <code>0</code> if this

     *          <code>Timestamp</code> object is before the given argument;

     *          and a value greater than <code>0</code> if this

     *          <code>Timestamp</code> object is after the given argument.

     * @since   1.4

     */

    public int compareTo(Timestamp ts) {

        long thisTime = this.getTime();

        long anotherTime = ts.getTime();

        int i = (thisTime<anotherTime ? -1 :(thisTime==anotherTime?0 :1));

        if (i == 0) {

            if (nanos > ts.nanos) {

                    return 1;

            } else if (nanos < ts.nanos) {

                return -1;

            }

        }

        return i;

    }

    /**

     * Compares this <code>Timestamp</code> object to the given

     * <code>Date</code> object.

     *

     * @param o the <code>Date</code> to be compared to

     *          this <code>Timestamp</code> object

     * @return  the value <code>0</code> if this <code>Timestamp</code> object

     *          and the given object are equal; a value less than <code>0</code>

     *          if this  <code>Timestamp</code> object is before the given argument;

     *          and a value greater than <code>0</code> if this

     *          <code>Timestamp</code> object is after the given argument.

     *

     * @since   1.5

     */

    public int compareTo(java.util.Date o) {

       if(o instanceof Timestamp) {

            // When Timestamp instance compare it with a Timestamp

            // Hence it is basically calling this.compareTo((Timestamp))o);

            // Note typecasting is safe because o is instance of Timestamp

           return compareTo((Timestamp)o);

      } else {

            // When Date doing a o.compareTo(this)

            // will give wrong results.

          Timestamp ts = new Timestamp(o.getTime());

          return this.compareTo(ts);

      }

    }

    static final long serialVersionUID = 2745179027874758501L;

}