Package org.apache.derby.iapi.types

Class SQLDate

  • All Implemented Interfaces:
    java.io.Externalizable, java.io.Serializable, java.lang.Comparable, Formatable, Storable, TypedFormat, DataValueDescriptor, DateTimeDataValue, Orderable
    public final class SQLDate
extends DataType
implements DateTimeDataValue
    This contains an instance of a SQL Date.

    The date is stored as int (year << 16 + month << 8 + day) Null is represented by an encodedDate value of 0. Some of the static methods in this class are also used by SQLTime and SQLTimestamp so check those classes if you change the date encoding PERFORMANCE OPTIMIZATION: The java.sql.Date object is only instantiated when needed do to the overhead of Date.valueOf(), etc. methods.

    See Also:
    Serialized Form

    • Field Detail

      • encodedDate

        private int encodedDate

      • BASE_MEMORY_USAGE

        private static final int BASE_MEMORY_USAGE

      • ISO_SEPARATOR_ONLY

        private static final char[] ISO_SEPARATOR_ONLY

      • IBM_USA_SEPARATOR_ONLY

        private static final char[] IBM_USA_SEPARATOR_ONLY

      • IBM_EUR_SEPARATOR_ONLY

        private static final char[] IBM_EUR_SEPARATOR_ONLY

      • END_OF_STRING

        private static final char[] END_OF_STRING

    • Constructor Detail

      • SQLDate

        public SQLDate()
        no-arg constructor required by Formattable

      • SQLDate

        private SQLDate​(int encodedDate)

      • SQLDate

        public SQLDate​(java.lang.String dateStr,
               boolean isJdbcEscape,
               LocaleFinder localeFinder)
        throws StandardException
        Construct a date from a string. The allowed date formats are:
        1. ISO: yyyy-mm-dd
        2. IBM USA standard: mm/dd/yyyy
        3. IBM European standard: dd.mm.yyyy
        Trailing blanks may be included; leading zeros may be omitted from the month and day portions.
        Parameters:
        dateStr -
        isJdbcEscape - if true then only the JDBC date escape syntax is allowed
        localeFinder -
        Throws:
        StandardException - if the syntax is invalid or the value is out of range

      • SQLDate

        public SQLDate​(java.lang.String dateStr,
               boolean isJdbcEscape,
               LocaleFinder localeFinder,
               java.util.Calendar cal)
        throws StandardException
        Construct a date from a string. The allowed date formats are:
        1. ISO: yyyy-mm-dd
        2. IBM USA standard: mm/dd/yyyy
        3. IBM European standard: dd.mm.yyyy
        Trailing blanks may be included; leading zeros may be omitted from the month and day portions.
        Parameters:
        dateStr -
        isJdbcEscape - if true then only the JDBC date escape syntax is allowed
        localeFinder -
        Throws:
        StandardException - if the syntax is invalid or the value is out of range

    • Method Detail

      • estimateMemoryUsage

        public int estimateMemoryUsage()
        Description copied from interface: DataValueDescriptor
        Estimate the memory usage in bytes of the data value and the overhead of the class.
        Specified by:
        estimateMemoryUsage in interface DataValueDescriptor
        Returns:
        the estimated memory usage

      • getEncodedDate

        int getEncodedDate()

      • getString

        public java.lang.String getString()
        Description copied from interface: DataValueDescriptor
        Gets the value in the data value descriptor as a String. Throws an exception if the data value is not a string.
        Specified by:
        getString in interface DataValueDescriptor
        Returns:
        The data value as a String.

      • getTimestamp

        public java.sql.Timestamp getTimestamp​(java.util.Calendar cal)
        getTimestamp returns a timestamp with the date value time is set to 00:00:00.0
        Specified by:
        getTimestamp in interface DataValueDescriptor
        Overrides:
        getTimestamp in class DataType
        Parameters:
        cal - calendar for object creation
        Returns:
        The data value as a java.sql.Timestamp.

      • getTimeInMillis

        private long getTimeInMillis​(java.util.Calendar cal)
        Convert the date into a milli-seconds since the epoch with the time set to 00:00 based upon the passed in Calendar.

      • setDateInCalendar

        static void setDateInCalendar​(java.util.Calendar cal,
                              int encodedDate)
        Set the date portion of a date-time value into the passed in Calendar object from its encodedDate value. Only the YEAR, MONTH and DAY_OF_MONTH fields are modified. The remaining state of the Calendar is not modified.

      • getLength

        public int getLength()
        Description copied from interface: DataValueDescriptor
        Gets the length of the data value. The meaning of this is implementation-dependent. For string types, it is the number of characters in the string. For numeric types, it is the number of bytes used to store the number. This is the actual length of this value, not the length of the type it was defined as. For example, a VARCHAR value may be shorter than the declared VARCHAR (maximum) length.
        Specified by:
        getLength in interface DataValueDescriptor
        Returns:
        The length of the data value

      • writeExternal

        public void writeExternal​(java.io.ObjectOutput out)
                   throws java.io.IOException
        Specified by:
        writeExternal in interface java.io.Externalizable
        Throws:
        java.io.IOException - error writing data

      • readExternal

        public void readExternal​(java.io.ObjectInput in)
                  throws java.io.IOException
        Specified by:
        readExternal in interface java.io.Externalizable
        Throws:
        java.io.IOException - Thrown on error reading the object
        See Also:
        Externalizable.readExternal(java.io.ObjectInput)

      • cloneValue

        public DataValueDescriptor cloneValue​(boolean forceMaterialization)
        Description copied from interface: DataValueDescriptor
        Clone this DataValueDescriptor. Results in a new object that has the same value as this but can be modified independently.

        Even though the objects can be modified independently regardless of the value of forceMaterialization, both the clone and the original may be dependent on the store state if forceMaterialization is set to false. An example is if you need to access the value you just read using cloneValue after the current transaction has ended, or after the source result set has been closed.

        Specified by:
        cloneValue in interface DataValueDescriptor
        Parameters:
        forceMaterialization - any streams representing the data value will be materialized if true, the data value will be kept as a stream if possible if false
        Returns:
        A clone of the DataValueDescriptor with the same initial value as this.
        See Also:
        DataValueDescriptor.cloneValue(boolean)

      • compare

        public int compare​(DataValueDescriptor other)
            throws StandardException
        Orderable interface
        Specified by:
        compare in interface DataValueDescriptor
        Parameters:
        other - The Orderable to compare this one to.
        Returns:
        <0 - this Orderable is less than other. 0 - this Orderable equals other. >0 - this Orderable is greater than other. The code should not explicitly look for -1, or 1.
        Throws:
        StandardException - thrown on failure
        See Also:
        Orderable

      • compare

        public boolean compare​(int op,
                       DataValueDescriptor other,
                       boolean orderedNulls,
                       boolean unknownRV)
                throws StandardException
        Description copied from interface: DataValueDescriptor
        Compare this Orderable with a given Orderable for the purpose of qualification and sorting. The caller gets to determine how nulls should be treated - they can either be ordered values or unknown values.
        Specified by:
        compare in interface DataValueDescriptor
        Overrides:
        compare in class DataType
        Parameters:
        op - Orderable.ORDER_OP_EQUALS means do an = comparison. Orderable.ORDER_OP_LESSTHAN means compare this < other. Orderable.ORDER_OP_LESSOREQUALS means compare this <= other.
        other - The DataValueDescriptor to compare this one to.
        orderedNulls - True means to treat nulls as ordered values, that is, treat SQL null as equal to null, and less than all other values. False means to treat nulls as unknown values, that is, the result of any comparison with a null is the UNKNOWN truth value.
        unknownRV - The return value to use if the result of the comparison is the UNKNOWN truth value. In other words, if orderedNulls is false, and a null is involved in the comparison, return unknownRV. This parameter is not used orderedNulls is true.
        Returns:
        true if the comparison is true (duh!)
        Throws:
        StandardException - thrown on error

      • setFrom

        protected void setFrom​(DataValueDescriptor theValue)
                throws StandardException
        Description copied from class: DataType
        Set the value of this DataValueDescriptor based on the value of the specified DataValueDescriptor.
        Overrides:
        setFrom in class DataType
        Parameters:
        theValue - The DataValueDescriptor that holds the value to which we want to set this DataValueDescriptor's value.
        Throws:
        StandardException

      • setValue

        public void setValue​(java.sql.Timestamp value,
                     java.util.Calendar cal)
              throws StandardException
        Description copied from class: DataType
        Set the value of this DataValueDescriptor. At DataType level just throws an error lower classes will override
        Specified by:
        setValue in interface DataValueDescriptor
        Overrides:
        setValue in class DataType
        Parameters:
        value - The Timestamp value to set this DataValueDescriptor to
        cal - The time zone from the calendar is used to construct the database timestamp value
        Throws:
        StandardException
        See Also:
        DataValueDescriptor.setValue(int)

      • setValue

        public void setValue​(java.lang.String theValue)
              throws StandardException
        Description copied from class: DataType
        Set the value of this DataValueDescriptor. At DataType level just throws an error lower classes will override
        Specified by:
        setValue in interface DataValueDescriptor
        Overrides:
        setValue in class DataType
        Parameters:
        theValue - The BigDecimal value to set this DataValueDescriptor to
        Throws:
        StandardException

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object

      • typePrecedence

        public int typePrecedence()
        Description copied from class: DataType
        Each built-in type in JSQL has a precedence. This precedence determines how to do type promotion when using binary operators. For example, float has a higher precedence than int, so when adding an int to a float, the result type is float. The precedence for some types is arbitrary. For example, it doesn't matter what the precedence of the boolean type is, since it can't be mixed with other types. But the precedence for the number types is critical. The SQL standard requires that exact numeric types be promoted to approximate numeric when one operator uses both. Also, the precedence is arranged so that one will not lose precision when promoting a type.
        Specified by:
        typePrecedence in interface DataValueDescriptor
        Overrides:
        typePrecedence in class DataType
        Returns:
        The precedence of this type.
        See Also:
        DataValueDescriptor.typePrecedence()

      • isNull

        public final boolean isNull()
        Check if the value is null. encodedDate is 0 if the value is null
        Specified by:
        isNull in interface Storable
        Returns:
        Whether or not value is logically null.

      • getDate

        public java.sql.Date getDate​(java.util.Calendar cal)
        Get the value field. We instantiate the field on demand.
        Specified by:
        getDate in interface DataValueDescriptor
        Overrides:
        getDate in class DataType
        Parameters:
        cal - calendar for object creation
        Returns:
        The value field.

      • getYear

        static int getYear​(int encodedDate)
        Get the year from the encodedDate.
        Parameters:
        encodedDate - the encoded date
        Returns:
        year value.

      • getMonth

        static int getMonth​(int encodedDate)
        Get the month from the encodedDate, January is one.
        Parameters:
        encodedDate - the encoded date
        Returns:
        month value.

      • getDay

        static int getDay​(int encodedDate)
        Get the day from the encodedDate.
        Parameters:
        encodedDate - the encoded date
        Returns:
        day value.

      • computeEncodedDate

        static int computeEncodedDate​(java.util.Calendar cal)
                       throws StandardException
        computeEncodedDate extracts the year, month and date from a Calendar value and encodes them as year << 16 + month << 8 + date Use this function will help to remember to add 1 to month which is 0 based in the Calendar class
        Parameters:
        cal - the Calendar
        Returns:
        the encodedDate
        Throws:
        StandardException - if the value is out of the DB2 date range

      • dateToString

        static void dateToString​(int year,
                         int month,
                         int day,
                         java.lang.StringBuffer sb)
        Convert a date to the JDBC representation and append it to a string buffer.
        Parameters:
        year -
        month - 1 based (January == 1)
        day -
        sb - The string representation is appended to this StringBuffer

      • encodedDateToString

        static java.lang.String encodedDateToString​(int encodedDate)
        Get the String version from the encodedDate.
        Returns:
        string value.

      • computeEncodedDate

        private static int computeEncodedDate​(java.util.Date value)
                               throws StandardException
        Compute the encoded date given a date
        Throws:
        StandardException

      • setInto

        public void setInto​(java.sql.PreparedStatement ps,
                    int position)
             throws java.sql.SQLException,
                    StandardException
        Adding this method to ensure that super class' setInto method doesn't get called that leads to the violation of JDBC spec( untyped nulls ) when batching is turned on.
        Specified by:
        setInto in interface DataValueDescriptor
        Overrides:
        setInto in class DataType
        Throws:
        java.sql.SQLException - thrown by the PreparedStatement object
        StandardException - thrown by me accessing my value.

      • timestampAdd

        public DateTimeDataValue timestampAdd​(int intervalType,
                                      NumberDataValue intervalCount,
                                      java.sql.Date currentDate,
                                      DateTimeDataValue resultHolder)
                               throws StandardException
        Add a number of intervals to a datetime value. Implements the JDBC escape TIMESTAMPADD function.
        Specified by:
        timestampAdd in interface DateTimeDataValue
        Parameters:
        intervalType - One of FRAC_SECOND_INTERVAL, SECOND_INTERVAL, MINUTE_INTERVAL, HOUR_INTERVAL, DAY_INTERVAL, WEEK_INTERVAL, MONTH_INTERVAL, QUARTER_INTERVAL, or YEAR_INTERVAL
        intervalCount - The number of intervals to add
        currentDate - Used to convert time to timestamp
        resultHolder - If non-null a DateTimeDataValue that can be used to hold the result. If null then generate a new holder
        Returns:
        startTime + intervalCount intervals, as a timestamp
        Throws:
        StandardException

      • timestampDiff

        public NumberDataValue timestampDiff​(int intervalType,
                                     DateTimeDataValue time1,
                                     java.sql.Date currentDate,
                                     NumberDataValue resultHolder)
                              throws StandardException
        Finds the difference between two datetime values as a number of intervals. Implements the JDBC TIMESTAMPDIFF escape function.
        Specified by:
        timestampDiff in interface DateTimeDataValue
        Parameters:
        intervalType - One of FRAC_SECOND_INTERVAL, SECOND_INTERVAL, MINUTE_INTERVAL, HOUR_INTERVAL, DAY_INTERVAL, WEEK_INTERVAL, MONTH_INTERVAL, QUARTER_INTERVAL, or YEAR_INTERVAL
        time1 -
        currentDate - Used to convert time to timestamp
        resultHolder - If non-null a NumberDataValue that can be used to hold the result. If null then generate a new holder
        Returns:
        the number of intervals by which this datetime is greater than time1
        Throws:
        StandardException