Package org.sqlite

Class Collation

java.lang.Object

org.sqlite.Collation

public abstract class Collation
extends Object

Provides an interface for creating SQLite user-defined collations.

A subclass of org.sqlite.Collation can be registered with Collation.create() and called by the name it was given. All collations must implement xCompare(String, String), which is called when SQLite compares two strings using the custom collation. Eg.

      Class.forName("org.sqlite.JDBC");
      Connection conn = DriverManager.getConnection("jdbc:sqlite:");

      Collation.create(conn, "REVERSE", new Collation() {
          protected int xCompare(String str1, String str2) {
              return str1.compareTo(str2) * -1;
          }
      });

      conn.createStatement().execute("select c1 from t order by c1 collate REVERSE;");
  

Constructor Summary

Constructors

Constructor	Description
Collation()

Method Summary

Modifier and Type	Method	Description
static final void	create(Connection conn, String name, Collation f)	Registers a given collation with the connection.
static final void	destroy(Connection conn, String name)	Removes a named collation from the given connection.
protected abstract int	xCompare(String str1, String str2)	Called by SQLite as a custom collation to compare two strings.

Methods inherited from class java.lang.Object

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

Constructor Details

Collation

public Collation()

Method Details

create

public static final void create(Connection conn,
 String name,
 Collation f)
                         throws SQLException

Registers a given collation with the connection.

Parameters:

conn - The connection.

name - The name of the collation.

f - The collation to register.

Throws:

SQLException

destroy

public static final void destroy(Connection conn,
 String name)
                          throws SQLException

Removes a named collation from the given connection.

Parameters:

conn - The connection to remove the collation from.

name - The name of the collation.

Throws:

SQLException

xCompare

protected abstract int xCompare(String str1,
 String str2)

Called by SQLite as a custom collation to compare two strings.

Parameters:

str1 - the first string in the comparison

str2 - the second string in the comparison

Returns:

an integer that is negative, zero, or positive if the first string is less than, equal to, or greater than the second, respectively