Package org.ggf.drmaa

Class PartialTimestamp

java.lang.Object
java.util.Calendar
org.ggf.drmaa.PartialTimestamp
All Implemented Interfaces:
Serializable, Cloneable, Comparable<Calendar>

public class PartialTimestamp extends Calendar
The PartialTimestamp is a subclass of java.util.Calendar that allows for a partially specified time that is resolved to the soonest matching time that is in the future at the time of resolution. That is to say that if one creates a PartialTimestamp instance and sets the hour to 10am and the minute to 0, and one resolves the time, i.e. PartialTimestamp.getTime(), at 11:01am on November 24th, the PartialTimestamp will resolve to 10:00am on November 25th, as that time is the soonest time which matches the specified fields and is in the future. If one later resolves that same PartialTimestamp instance at 9:34am on December 1st, it will resolve to 10:00am on December 1st.

There are only two ways to resolve the time: getTime() and getTimeInMillis(). All other means of accessing field values will return unresolved values. If the PartialTimestamp class is unable to resolve a field because of other unset fields, it will simply leave the field unresolved. For example, if the DAY_OF_MONTH is set to 42, and the MONTH is unset, the DAY_OF_MONTH will remain as 42. If later the MONTH is set, the DAY_OF_MONTH may be resolved to an in-range value. ("May," because if the MONTH is FEBRUARY, the YEAR and CENTURY are also needed to be able to resolve the DAY_OF_MONTH.)

Whereever possible and sensible, the PartialTimestamp class mimics the functionality of the GregorianCalendar class.

Since the PartialTimestamp only supports dates within the epoch, the ERA field is always AD, and hence is not used. The DRMAA specification, requires that the year be handled as two separate fields, one for the first n-2 digits (century) and one for the last two digits. Because of the symantics of extending the Calendar class, the CENTURY field is just an alias for the ERA field, and the ERA contains the century data. When using the PartialTimestmap class, the ERA field should not be used.

When rolling a date field, if the PartialTimestamp doesn't have enough information to determine the field's valid value range, e.g. when rolling the DAY_OF_MONTH while MONTH is unset, an assumption will be made. The assumptions a PartialTimestamp instance may make are: a year is 365 days or 53 weeks, and a month is 31 days or 5 weeks.

The PartialTimestamp class adds the idea of field modifiers to the Calendar class. Field modifiers are accessed via the setModifier() and getModifier() methods. A modifier represents a number that will be added to the value of the field. This is useful because in a PartialTimestamp instance, it may necessary to add to an unset field, for example to indicate the concept of "tomorrow." If an add() method or out of range set() method attempts to modify an unset field, the resulting modifier will be stored as the modifier for that field. For example, if the MONTH is set to DECEMBER, and the YEAR is unset, and 1 is added to the MONTH, the result will be that the MONTH is set to JANUARY, the year is still unset, and the YEAR modifier is set to 1. If later the YEAR is set to 97, the modifier will be applied, resulting in a year of 98. To avoid unwanted modifiers, use the roll() method instead of the add() method.

The roll() method in the PartialTimestamp class is very simple. It does not take into account Daylight Savings Time or other complications, as does the roll() method of the GregorianCalendar.

Example:

public static void main (String[] args) {
   SessionFactory factory = SessionFactory.getFactory ();
   Session session = factory.getSession ();

   try {
      session.init (null);
      JobTemplate jt = session.createJobTemplate ();
      jt.setRemoteCommand ("sleeper.sh");
      jt.setArgs (new String[] {"5"});

      PartialTimestamp date = new PartialTimestamp ();

      // Run the job on the first of the month at 11:30
      date.set (PartialTimestamp.DATE, 1);
      date.set (PartialTimestamp.HOUR_OF_DAY, 11);
      date.set (PartialTimestamp.MINUTE, 30);

      jt.setStartTime (date);

      String id = session.runJob (jt);

      session.deleteJobTemplate (jt);
      session.exit ();
   }
   catch (DrmaaException e) {
      System.out.println ("Error: " + e.getMessage ());
   }
 }
 
Since:
0.5
Version:
1.0
See Also:
  • Field Details

    • CENTURY

      public static final int CENTURY
      CENTURY is a field required by the DRMAA timestamp.
      See Also:
    • UNSET

      public static final int UNSET
      UNSET is the value assigned to fields which have not yet been set.
      See Also:
  • Constructor Details

    • PartialTimestamp

      public PartialTimestamp()
      Constructs a default PartialTimestamp instance using the current time in the default time zone with the default locale.
    • PartialTimestamp

      public PartialTimestamp(TimeZone zone)
      Constructs a PartialTimestamp instance based on the current time in the given time zone with the default locale.
      Parameters:
      zone - the given time zone.
    • PartialTimestamp

      public PartialTimestamp(Locale aLocale)
      Constructs a PartialTimestamp instance based on the current time in the default time zone with the given locale.
      Parameters:
      aLocale - the given locale.
    • PartialTimestamp

      public PartialTimestamp(TimeZone zone, Locale aLocale)
      Constructs a PartialTimestamp instance based on the current time in the given time zone with the given locale.
      Parameters:
      zone - the given time zone.
      aLocale - the given locale.
    • PartialTimestamp

      public PartialTimestamp(int year, int month, int date, int hour, int minute)
      Constructs a PartialTimestamp instance with the given date and time set for the default time zone with the default locale.
      Parameters:
      year - the value used to set the YEAR time field in the calendar.
      month - the value used to set the MONTH time field in the calendar. Month value is 0-based. e.g., 0 for January.
      date - the value used to set the DATE time field in the calendar.
      hour - the value used to set the HOUR_OF_DAY time field in the calendar.
      minute - the value used to set the MINUTE time field in the calendar.
    • PartialTimestamp

      public PartialTimestamp(int hour, int minute, int second)
      Constructs a PartialTimestamp instance with the given date and time set for the default time zone with the default locale.
      Parameters:
      hour - the value used to set the HOUR_OF_DAY time field in the calendar.
      minute - the value used to set the MINUTE time field in the calendar.
      second - the value used to set the SECOND time field in the calendar.
    • PartialTimestamp

      public PartialTimestamp(int year, int month, int date, int hour, int minute, int second)
      Constructs a PartialTimestamp instance with the given date and time set for the default time zone with the default locale.
      Parameters:
      year - the value used to set the YEAR time field in the calendar.
      month - the value used to set the MONTH time field in the calendar. Month value is 0-based. e.g., 0 for January.
      date - the value used to set the DATE time field in the calendar.
      hour - the value used to set the HOUR_OF_DAY time field in the calendar.
      minute - the value used to set the MINUTE time field in the calendar.
      second - the value used to set the SECOND time field in the calendar.
  • Method Details

    • getModifier

      public int getModifier(int field)
      Returns the value of the modifier for the given field.
      Parameters:
      field - the field whose modifier will be returned
      Returns:
      the value of the field's modifier
    • setModifier

      public void setModifier(int field, int value)
      Sets the value of the modifier for the given field.
      Parameters:
      field - the field whose modifier will be set
      value - the value to which to set the field's modifier
    • add

      public void add(int field, int amount)
      Adds the given value to the given field. If the field is unset, the amount will be added to the field's modifier instead. If the field is set, but the addition causes changes to another field, which is unset, the unset field will receive the change as a modifier.
      Specified by:
      add in class Calendar
      Parameters:
      field - the field to which to add the amount
      amount - the amount to add
    • set

      public void set(int field, int value)
      Sets the value of the given field. After a call to set, the field is considered set. There is no way to unset a field that has been previously set. If the value is out of range for the field, it will be adjusted to be within range, if possible. If, because of other unset fields, there is not enough information to adjust the field, the field will remain as set.
      Overrides:
      set in class Calendar
      Parameters:
      field - the field to set
      value - the value to which to set the field
    • get

      public int get(int field)
      Get the value of the given field. If the field is unset, this method will return UNSET.
      Overrides:
      get in class Calendar
      Parameters:
      field - which field's value to get
      Returns:
      The value of the field.
    • getGreatestMinimum

      public int getGreatestMinimum(int field)
      Gets the greatest minimum value that the field may ever have.
      Specified by:
      getGreatestMinimum in class Calendar
      Parameters:
      field - the field of interest
      Returns:
      the greatest minimum value that the field may ever have
    • getLeastMaximum

      public int getLeastMaximum(int field)
      Gets the least maximum value that the field may ever have.
      Specified by:
      getLeastMaximum in class Calendar
      Parameters:
      field - the field of interest
      Returns:
      the least maximum value that the field may ever have
    • getMaximum

      public int getMaximum(int field)
      Gets the greatest maximum value that the field may ever have.
      Specified by:
      getMaximum in class Calendar
      Parameters:
      field - the field of interest
      Returns:
      the greatest maximum value that the field may ever have
    • getMinimum

      public int getMinimum(int field)
      Gets the least minimum value that the field may ever have.
      Specified by:
      getMinimum in class Calendar
      Parameters:
      field - the field of interest
      Returns:
      the least minimum value that the field may ever have
    • roll

      public void roll(int field, boolean up)
      This method naively rolls the value of the given field by 1, either up or down. If the resulting value is out of range for the field, the value will roll over without affecting other fields.
      Specified by:
      roll in class Calendar
      Parameters:
      field - the field to roll
      up - whether to roll up
    • roll

      public void roll(int field, int amount)
      This method naively rolls the value of the given field up by the given amount. To roll down, use a negative amount. If the resulting value is out of range for the field, the value will roll over without affecting other fields.
      Overrides:
      roll in class Calendar
      Parameters:
      field - the field to roll
      amount - the amount to roll up
    • getActualMinimum

      public int getActualMinimum(int field)
      Returns the actual minimum value for the field, based on the current field values.
      Overrides:
      getActualMinimum in class Calendar
      Parameters:
      field - the field of interest
      Returns:
      the actual minimum value for the field
    • getActualMaximum

      public int getActualMaximum(int field)
      Returns the actual maximum value for the field, based on the current field values.
      Overrides:
      getActualMaximum in class Calendar
      Parameters:
      field - the field of interest
      Returns:
      the actual maximum value for the field
    • equals

      public boolean equals(Object obj)
      Compares two PartialTimestamp objects. They are equal if they both have all of the same field values and field modifier values.
      Overrides:
      equals in class Calendar
      Parameters:
      obj - the object against which to compare
      Returns:
      whether the given object equals this object
    • clone

      public Object clone()
      Makes a complete copy of this object.
      Overrides:
      clone in class Calendar
      Returns:
      a complete copy of this object