Package redempt.redlib.sql

Class SQLCache

java.lang.Object

redempt.redlib.sql.SQLCache

public class SQLCache
extends Object

A cache to store the values in a single column of a single SQL table

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	SQLCache(SQLHelper sql, String tableName, String columnName, String... primaryKeyNames)

Method Summary

Modifier and Type	Method	Description
void	clear()	Clears the cache.
void	delete(Object... primaryKeys)	Deletes a row from the table by its primary keys, and removes it from the cache.
void	flush()	Flushes the cache, saving all changes that were made.
void	flush(Object... primaryKeys)	Flushes a single value from the cache, saving changes that were made to it
String	getColumnName()
String[]	getPrimaryKeyNames()
String	getTableName()
boolean	isCached(Object... primaryKeys)	Checks whether a value has been cached by its primary keys
protected boolean	keyNamesMatch(String[] matches)
void	remove(Object... primaryKeys)	Removes a cached value, but does not affect the table
<T> T	select(Object... primaryKeys)	Gets the cached value for a row, or queries it if it has not been cached yet
Long	selectLong(Object... primaryKeys)	Gets the cached value for a Long row, or queries it if it has not been cached yet
String	selectString(Object... primaryKeys)	Gets the cached value for a String row, or queries it if it has not been cached yet
void	update(Object value, Object... primaryKeys)	Updates the cached value for a row

Methods inherited from class java.lang.Object

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

Constructor Details

SQLCache

protected SQLCache(SQLHelper sql,
 String tableName,
 String columnName,
 String... primaryKeyNames)

Method Details

getTableName

public String getTableName()

Returns:

The name of the table this SQLCache is for

getColumnName

public String getColumnName()

Returns:

The name of the column this SQLCache is for

getPrimaryKeyNames

public String[] getPrimaryKeyNames()

Returns:

The names of the primary keys used to access and mutate the column this SQLCache is for

keyNamesMatch

protected boolean keyNamesMatch(String[] matches)

delete

public void delete(Object... primaryKeys)

Deletes a row from the table by its primary keys, and removes it from the cache. This operation will always use a query.

Parameters:

primaryKeys - The keys to use to delete the row

remove

public void remove(Object... primaryKeys)

Removes a cached value, but does not affect the table

Parameters:

primaryKeys - The keys used to access the value

update

public void update(Object value,
 Object... primaryKeys)

Updates the cached value for a row

Parameters:

value - The value to cache

primaryKeys - The primary keys used to mutate the row

select

public <T> T select(Object... primaryKeys)

Gets the cached value for a row, or queries it if it has not been cached yet

Type Parameters:

T - The type of the value

Parameters:

primaryKeys - The primary keys used to access the row

Returns:

The value

selectString

public String selectString(Object... primaryKeys)

Gets the cached value for a String row, or queries it if it has not been cached yet

Parameters:

primaryKeys - The primary keys used to access the row

Returns:

The String value

selectLong

public Long selectLong(Object... primaryKeys)

Gets the cached value for a Long row, or queries it if it has not been cached yet

Parameters:

primaryKeys - The primary keys used to access the row

Returns:

The Long value

isCached

public boolean isCached(Object... primaryKeys)

Checks whether a value has been cached by its primary keys

Parameters:

primaryKeys - The primary keys used to access the row

Returns:

Whether the value has been cached

clear

public void clear()

Clears the cache. WARNING: This will revert all changes that have not been flushed! No updates performed through update(Object, Object...) will be committed!

flush

public void flush()

Flushes the cache, saving all changes that were made.

flush

public void flush(Object... primaryKeys)

Flushes a single value from the cache, saving changes that were made to it

Parameters:

primaryKeys - The primary keys used to access the row