com.whitestein.lsps.vaadin.ui.components.table.dataset

Class QueryDataset

java.lang.Object

com.whitestein.lsps.vaadin.ui.components.table.dataset.QueryDataset

All Implemented Interfaces:

IDataset

public class QueryDataset
extends Object
implements IDataset

Provides data by invoking given LSPS Query function.

Author:

mvy

Constructor Summary

Constructors

Constructor and Description
QueryDataset(Variant.ScopedClosureVariant closure, ExecutionContext executionContext)

Method Summary

Modifier and Type	Method and Description
Type	getItemType() Returns the type of data returned by the load functions.
boolean	isFilterSupported(Filter filter) True if given filter criterion is supported.
boolean	isSortSupported(ISort criterion) True if given sort criterion is supported.
List<Object>	load(int startIndex, int count) Load batch of items, mostly records or simple types.
void	setFilter(Set<Filter> filters) Sets the new filtering criteria.
void	setSort(SortSpec sort) Sets the new sorting criteria.
int	size() Gets number of items available through this query.

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryDataset

public QueryDataset(Variant.ScopedClosureVariant closure,
                    ExecutionContext executionContext)

Method Detail

isSortSupported

public boolean isSortSupported(ISort criterion)

Description copied from interface: IDataset

True if given sort criterion is supported.

Specified by:

isSortSupported in interface IDataset

Parameters:

criterion - the criterion, not null.

Returns:

true if given sort criterion is supported, false if not.

isFilterSupported

public boolean isFilterSupported(Filter filter)

Description copied from interface: IDataset

True if given filter criterion is supported.

Specified by:

isFilterSupported in interface IDataset

Parameters:

filter - the filter, not null.

Returns:

true if given filter is supported, false if not.

setSort

public void setSort(SortSpec sort)

Description copied from interface: IDataset

Sets the new sorting criteria. This class should sort based on concrete implementations of ISort and must ignore sort criteria classes of unknown/unsupported types. Next call to IDataset.load(int, int) must return sorted filtered data.

Specified by:

setSort in interface IDataset

Parameters:

sort - the sorting criteria, not null.

setFilter

public void setFilter(Set<Filter> filters)

Description copied from interface: IDataset

Sets the new filtering criteria. This class should filter based on concrete implementations of ISort and must ignore filter criteria classes of unknown/unsupported types. Next call to IDataset.load(int, int) must return properly filtered data.

Specified by:

setFilter in interface IDataset

Parameters:

filters - the filtering criteria, not null, may be empty. Silently ignore unsupported filters.

load

public List<Object> load(int startIndex,
                         int count)

Description copied from interface: IDataset

Load batch of items, mostly records or simple types. The items must be sorted and filtered accordingly, as stated by last call to IDataset.setSort(SortSpec) and/or IDataset.setFilter(java.util.Set) respectively.

Specified by:

load in interface IDataset

Parameters:

startIndex - Starting index of the item list, must be 0 or greater.

count - Count of the items to be retrieved, must be 0 or greater.

Returns:

List of items, mostly RecordHolders. Should never fail with out of bounds exception - if the startIndex or count is out of bounds, the item is simply not returned. The list may or may not be mutable.

size

public int size()

Description copied from interface: IDataset

Gets number of items available through this query.

Specified by:

size in interface IDataset

Returns:

Number of items. Only count items which pass filters.

getItemType

public Type getItemType()

Description copied from interface: IDataset

Returns the type of data returned by the load functions. Returns Object if the type cannot be guessed.

Specified by:

getItemType in interface IDataset

Returns:

the type, never null.