Package adams.db.queries

Class AbstractDatabaseQueries

java.lang.Object

adams.db.queries.AbstractDatabaseQueries

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

QueriesH2, QueriesMSSQL, QueriesMySQL, QueriesPostgreSQL, QueriesSQLite

public abstract class AbstractDatabaseQueries
extends Object
implements Serializable

Ancestor for SQL queries classes.

Author:

FracPete (fracpete at waikato dot ac dot nz)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected static Map<String,AbstractDatabaseQueries>	m_Cache	for caching types on URLs.
protected static List<AbstractDatabaseQueries>	m_Types	the available types.

Constructor Summary

Constructors

Constructor	Description
AbstractDatabaseQueries()

Method Summary

Modifier and Type	Method	Description
static AbstractDatabaseQueries	getHandler(String url)	Returns the handler for the JDBC url.
abstract boolean	handles(String url)	Checks whether this URL is handled.
String	limit(int max)	Generates the row limiting expression.
abstract String	limitKeyword()	Returns the keyword/expression for limiting the number of rows.
String	regexp(String col, BaseRegExp expr)	Generates a regexp expression from the column and regular expression.
String	regexp(String col, String expr)	Generates a regexp expression from the column and regular expression.
abstract String	regexpKeyword()	Returns the keyword for regular expression matching in queries.

Methods inherited from class java.lang.Object

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

Field Detail

m_Cache

protected static Map<String,AbstractDatabaseQueries> m_Cache

for caching types on URLs.

m_Types

protected static List<AbstractDatabaseQueries> m_Types

the available types.

Constructor Detail

AbstractDatabaseQueries

public AbstractDatabaseQueries()

Method Detail

regexpKeyword

public abstract String regexpKeyword()

Returns the keyword for regular expression matching in queries.

Returns:

the keyword

regexp

public String regexp(String col,
                     BaseRegExp expr)

Generates a regexp expression from the column and regular expression.

Returns:

the expression

regexp

public String regexp(String col,
                     String expr)

Generates a regexp expression from the column and regular expression.

Returns:

the expression

limitKeyword

public abstract String limitKeyword()

Returns the keyword/expression for limiting the number of rows.

Returns:

the keyword/expression

limit

public String limit(int max)

Generates the row limiting expression. NB: requires an ORDER BY in the statement.

Parameters:

max - the maximum number of rows to return

Returns:

the expression

handles

public abstract boolean handles(String url)

Checks whether this URL is handled.

Parameters:

url - the URL to check

Returns:

true if handled by this type class

getHandler

public static AbstractDatabaseQueries getHandler(String url)

Returns the handler for the JDBC url.

Parameters:

url - the URL

Returns:

the handler, null if no support available