📄 library.java
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/**
* Returns the second of the given time value, as an integer value in
* the range of 0-59.
*
* @param d the date value from which to extract the second of the hour
* @return an integer representing the second of the hour from the
* given time value
*/
public static Integer second(Time d) {
if (d == null) {
return null;
}
return ValuePool.getInt(HsqlDateTime.getDateTimePart(d,
Calendar.SECOND));
}
/**
* Returns the week of the year from the given date value, as an integer
* value in the range of 1-53. <p>
*
* @param d the date value from which to extract the week of the year
* @return an integer representing the week of the year from the given
* date value
*/
public static Integer week(Date d) {
if (d == null) {
return null;
}
return ValuePool.getInt(HsqlDateTime.getDateTimePart(d,
Calendar.WEEK_OF_YEAR));
}
/**
* Returns the year from the given date value, as an integer value in
* the range of 1-9999. <p>
*
* @param d the date value from which to extract the year
* @return an integer value representing the year from the given
* date value
*/
public static Integer year(Date d) {
if (d == null) {
return null;
}
return ValuePool.getInt(HsqlDateTime.getDateTimePart(d,
Calendar.YEAR));
}
/**
* @since 1.8.0
*/
public static String to_char(java.util.Date d, String format) {
if (d == null || format == null) {
return null;
}
synchronized (tocharFormat) {
tocharFormat.applyPattern(HsqlDateTime.toJavaDatePattern(format));
return tocharFormat.format(d);
}
}
// date calculations.
/**
* Returns the number of units elapsed between two dates.<p>
* The datapart parameter indicates the part to be used for computing the
* difference. Supported types include: 'year', 'yy', 'month', 'mm'
* 'day', 'dd', 'hour', 'hh', 'minute', 'mi', 'second', 'ss', 'millisecond',
* 'ms'.
*
* Contributed by Michael Landon<p>
*
* @param datepart Specifies the unit in which the interval is to be measured.
* @param d1 The starting datetime value for the interval. This value is
* subtracted from d2 to return the number of
* date-parts between the two arguments.
* @param d2 The ending datetime for the interval. d1 is subtracted
* from this value to return the number of date-parts
* between the two arguments.
*
* since 1.7.3
*/
public static Long datediff(String datepart, Timestamp d1,
Timestamp d2) throws HsqlException {
// make sure we've got valid data
if (d1 == null || d2 == null) {
return null;
}
if ("yy".equalsIgnoreCase(datepart)
|| "year".equalsIgnoreCase(datepart)) {
return ValuePool.getLong(getElapsed(Calendar.YEAR, d1, d2));
} else if ("mm".equalsIgnoreCase(datepart)
|| "month".equalsIgnoreCase(datepart)) {
return ValuePool.getLong(getElapsed(Calendar.MONTH, d1, d2));
} else if ("dd".equalsIgnoreCase(datepart)
|| "day".equalsIgnoreCase(datepart)) {
return ValuePool.getLong(getElapsed(Calendar.DATE, d1, d2));
} else if ("hh".equalsIgnoreCase(datepart)
|| "hour".equalsIgnoreCase(datepart)) {
return ValuePool.getLong(getElapsed(Calendar.HOUR, d1, d2));
} else if ("mi".equalsIgnoreCase(datepart)
|| "minute".equalsIgnoreCase(datepart)) {
return ValuePool.getLong(getElapsed(Calendar.MINUTE, d1, d2));
} else if ("ss".equalsIgnoreCase(datepart)
|| "second".equalsIgnoreCase(datepart)) {
return ValuePool.getLong(getElapsed(Calendar.SECOND, d1, d2));
} else if ("ms".equalsIgnoreCase(datepart)
|| "millisecond".equalsIgnoreCase(datepart)) {
return ValuePool.getLong(getElapsed(Calendar.MILLISECOND, d1,
d2));
} else {
throw Trace.error(Trace.INVALID_CONVERSION);
}
}
/**
* Private method used to do actual calculation units elapsed between
* two given dates. <p>
*
* @param field Calendar field to use to calculate elapsed time
* @param d1 The starting date for the interval. This value is
* subtracted from d2 to return the number of
* date-parts between the two arguments.
* @param d2 The ending date for the interval. d1 is subtracted
* from this value to return the number of date-parts
* between the two arguments.
*/
private static long getElapsed(int field, java.util.Date d1,
java.util.Date d2) {
// can we do this very simply?
if (field == Calendar.MILLISECOND) {
return d2.getTime() - d1.getTime();
}
// ok, let's work a little harder:
Calendar g1 = Calendar.getInstance(),
g2 = Calendar.getInstance();
g1.setTime(d1);
g2.setTime(d2);
g1.set(Calendar.MILLISECOND, 0);
g2.set(Calendar.MILLISECOND, 0);
if (field == Calendar.SECOND) {
return (g2.getTime().getTime() - g1.getTime().getTime()) / 1000;
}
g1.set(Calendar.SECOND, 0);
g2.set(Calendar.SECOND, 0);
if (field == Calendar.MINUTE) {
return (g2.getTime().getTime() - g1.getTime().getTime())
/ (1000 * 60);
}
g1.set(Calendar.MINUTE, 0);
g2.set(Calendar.MINUTE, 0);
if (field == Calendar.HOUR) {
return (g2.getTime().getTime() - g1.getTime().getTime())
/ (1000 * 60 * 60);
} // end if-else
// if we got here, then we really need to work:
long elapsed = 0;
short sign = 1;
if (g2.before(g1)) {
sign = -1;
Calendar tmp = g1;
g1 = g2;
g2 = tmp;
} // end if
g1.set(Calendar.HOUR_OF_DAY, 0);
g2.set(Calendar.HOUR_OF_DAY, 0);
if (field == Calendar.MONTH || field == Calendar.YEAR) {
g1.set(Calendar.DATE, 1);
g2.set(Calendar.DATE, 1);
}
if (field == Calendar.YEAR) {
g1.set(Calendar.MONTH, 1);
g2.set(Calendar.MONTH, 1);
} // end if-else
// then calculate elapsed units
while (g1.before(g2)) {
g1.add(field, 1);
elapsed++;
}
return sign * elapsed;
} // end getElapsed
// SYSTEM
/*
* All system functions that return Session dependent information are
* dummies here.
*/
/**
* Returns the name of the database corresponding to this connection.
*
* @param conn the connection for which to retrieve the database name
* @return the name of the database for the given connection
* @throws HsqlException if a database access error occurs
*/
public static String database(Connection conn) throws HsqlException {
return null;
}
/**
* Returns the user's authorization name (the user's name as known to this
* database).
*
* @param conn the connection for which to retrieve the user name
* @return the user's name as known to the database
* @throws HsqlException if a database access error occurs
*/
public static String user(Connection conn) throws HsqlException {
return null;
}
/**
* Retrieves the last auto-generated integer indentity value
* used by this connection. <p>
*
* Dummy mehtod.<p>
*
* @return the connection's the last generated integer identity value
* @throws HsqlException if a database access error occurs
*/
public static int identity() throws HsqlException {
return 0;
}
// JDBC SYSTEM
/**
* Retrieves the autocommit status of this connection. <p>
*
* @param conn the <code>Connection</code> object for which to retrieve
* the current autocommit status
* @return a boolean value representing the connection's autocommit status
* @since 1.7.0
*/
public static boolean getAutoCommit(Connection conn) {
return false;
}
/**
* Retrieves the full version number of this database product. <p>
*
* @return database version number as a <code>String</code> object
* @since 1.8.0.4
*/
public static String getDatabaseFullProductVersion() {
return HsqlDatabaseProperties.THIS_FULL_VERSION;
}
/**
* Retrieves the name of this database product. <p>
*
* @return database product name as a <code>String</code> object
* @since 1.7.2
*/
public static String getDatabaseProductName() {
return HsqlDatabaseProperties.PRODUCT_NAME;
}
/**
* Retrieves the version number of this database product. <p>
*
* @return database version number as a <code>String</code> object
* @since 1.7.2
*/
public static String getDatabaseProductVersion() {
return HsqlDatabaseProperties.THIS_VERSION;
}
/**
* Retrieves the major version number of this database. <p>
*
* @return the database's major version as an <code>int</code> value
* @since 1.7.2
*/
public static int getDatabaseMajorVersion() {
return HsqlDatabaseProperties.MAJOR;
}
/**
* Retrieves the major version number of this database. <p>
*
* @return the database's major version as an <code>int</code> value
* @since 1.7.2
*/
public static int getDatabaseMinorVersion() {
return HsqlDatabaseProperties.MINOR;
}
/**
* Retrieves whether this connection is in read-only mode. <p>
*
* Dummy mehtod.<p>
*
* @param conn the <code>Connection</code> object for which to retrieve
* the current read-only status
* @return <code>true</code> if connection is read-only and
* <code>false</code> otherwise
* @since 1.7.2
*/
public static boolean isReadOnlyConnection(Connection conn) {
return false;
}
/**
* Dummy method. Retrieves whether this database is in read-only mode. <p>
*
* @param c the <code>Connection</code> object for which to retrieve
* the current database read-only status
* @return <code>true</code> if so; <code>false</code> otherwise
* @since 1.7.2
*/
public static boolean isReadOnlyDatabase(Connection c) {
return false;
}
/**
* Retrieves whether the files of this database are in read-only mode. <p>
*
* Dummy mehtod.<p>
*
* @param c the <code>Connection</code> object for which to retrieve
* the current database files read-only status
* @return <code>true</code> if so; <code>false</code> otherwise
* @since 1.7.2
*/
public static boolean isReadOnlyDatabaseFiles(Connection c) {
return false;
}
static final int abs = 0;
static final int ascii = 1;
static final int bitand = 2;
static final int bitLength = 3;
static final int bitor = 4;
static final int bitxor = 5;
static final int character = 6;
static final int concat = 7;
static final int cot = 8;
static final int curdate = 9;
static final int curtime = 10;
static final int database = 11;
static final int datediff = 12;
static final int day = 13;
static final int dayname = 14;
static final int dayofmonth = 15;
static final int dayofweek = 16;
static final int dayofyear = 17;
static final int difference = 18;
static final int getAutoCommit = 19;
static final int getDatabaseFullProductVersi⌨️ 快捷键说明
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