org.apache.derby.client.am

Class DateTime

java.lang.Object

org.apache.derby.client.am.DateTime

public class DateTime
extends java.lang.Object

High performance converters from date/time byte encodings to JDBC Date, Time and Timestamp objects.

Using this class for direct date/time conversions from bytes offers superior performance over the alternative method of first constructing a Java String from the encoded bytes, and then using java.sql.Date.valueOf(), java.sql.Time.valueOf() or java.sql.Timestamp.valueOf().

Method Summary

Modifier and Type	Method and Description
static int	dateToDateBytes(byte[] buffer, int offset, DateTimeValue date) Date is converted to a char representation in JDBC date format: yyyy-mm-dd date format and then converted to bytes using UTF8 encoding
static int	getTimestampLength(boolean supportsTimestampNanoseconds) Return the length of a timestamp depending on whether timestamps should have full nanosecond precision or be truncated to just microseconds.
static int	timestampToTimestampBytes(byte[] buffer, int offset, DateTimeValue timestamp, boolean supportsTimestampNanoseconds) See getTimestampLength() for an explanation of how timestamps are formatted.
static int	timeToTimeBytes(byte[] buffer, int offset, DateTimeValue time) java.sql.Time is converted to character representation which is in JDBC time escape format: hh:mm:ss, which is the same as JIS time format in DERBY string representation of a time.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

dateToDateBytes

public static final int dateToDateBytes(byte[] buffer,
                                        int offset,
                                        DateTimeValue date)
                                 throws SqlException

Date is converted to a char representation in JDBC date format: yyyy-mm-dd date format and then converted to bytes using UTF8 encoding

Parameters:

buffer - bytes in UTF8 encoding of the date

offset - write into the buffer from this offset

date - date value

Returns:

DateTime.dateRepresentationLength. This is the fixed length in bytes taken to represent the date value

Throws:

SqlException

timeToTimeBytes

public static final int timeToTimeBytes(byte[] buffer,
                                        int offset,
                                        DateTimeValue time)

java.sql.Time is converted to character representation which is in JDBC time escape format: hh:mm:ss, which is the same as JIS time format in DERBY string representation of a time. The char representation is converted to bytes using UTF8 encoding.

Parameters:

buffer - bytes in UTF8 encoding of the time

offset - write into the buffer from this offset

time - java.sql.Time value

Returns:

DateTime.timeRepresentationLength. This is the fixed length in bytes taken to represent the time value

timestampToTimestampBytes

public static final int timestampToTimestampBytes(byte[] buffer,
                                                  int offset,
                                                  DateTimeValue timestamp,
                                                  boolean supportsTimestampNanoseconds)
                                           throws SqlException

See getTimestampLength() for an explanation of how timestamps are formatted.

Parameters:

buffer - bytes in UTF8 encoding of the timestamp

offset - write into the buffer from this offset

timestamp - timestamp value

supportsTimestampNanoseconds - true if the server supports nanoseconds in timestamps

Returns:

DateTime.timestampRepresentationLength. This is the fixed length in bytes, taken to represent the timestamp value

Throws:

SqlException

getTimestampLength

public static int getTimestampLength(boolean supportsTimestampNanoseconds)

Return the length of a timestamp depending on whether timestamps should have full nanosecond precision or be truncated to just microseconds. java.sql.Timestamp is converted to a character representation which is a DERBY string representation of a timestamp converted to bytes using UTF8 encoding. For Derby 10.6 and above, this is yyyy-mm-dd-hh.mm.ss.fffffffff. For Derby 10.5 and below, this is yyyy-mm-dd-hh.mm.ss.ffffff. See DERBY-2602. and then converted to bytes using UTF8 encoding

Parameters:

supportsTimestampNanoseconds - true if the connection supports nanoseconds in timestamps