org.gvsig.fmap.dal.feature

Interface FeatureQuery

All Superinterfaces:

java.lang.Cloneable, DataQuery, Persistent, SupportFromJson, SupportJson, SupportToJson

All Known Implementing Classes:

DefaultFeatureQuery

public interface FeatureQuery
extends DataQuery, Cloneable, SupportJson

Defines the properties of a collection of Features, as a result of a query through a FeatureStore.

A FeatureQuery is always defined by a FeatureType, or by the list of attribute names of the FeatureStore to return.

The filter allows to select Features whose properties have values with the characteristics defined by the filter.

The order is used to set the order of the result FeatureCollection, based on the values of the properties of the Features.

The scale parameter can be used by the FeatureStore as a hint about the quality or resolution of the data needed to view or operate with the data returned. As an example, the FeatureStore may use the scale to return only a representative subset of the data, or maybe to return Features with less detail, like a point or a line instead of a polygon.

If an implementation of FeatureStore is able to get other parameters to customize the behavior of the getDataCollection methods, there is an option to set more parameters through the setAttribute method.

Field Summary

Fields

Modifier and Type	Field and Description
static int	NO_LIMIT

Method Summary

Modifier and Type	Method and Description
void	addAggregate(java.lang.String funcName, java.lang.String columnName)
void	addAttributeName(java.lang.String attributeName) Adds the name of an attribute that has to be used to load each Feature.
void	addConstantAttributeName(java.lang.String attributeName) Add an attribute name that will be treated as constant for each Feature.
void	addEssentialAttributeNames(FeatureStore store)
void	addFilter(Evaluator filter) Adds a filter to apply to the Features to load.
void	addFilter(Expression filter)
void	addFilter(java.lang.String filter)
void	addPrimaryKeyAttributeNames(FeatureStore store)
void	clearAttributeNames() Remove all the attribute names specifieds.
void	clearConstantsAttributeNames() Remove all the names specified as constants attributes.
void	clearFilter()
void	clearLimit()
void	copyFrom(FeatureQuery query)
java.lang.String	getAggregate(java.lang.String name) Deprecated.
java.lang.String	getAggregate(java.lang.String tableName, java.lang.String name)
java.lang.String	getAggregateFunction(java.lang.String name)
java.util.Map<java.lang.String,java.lang.String>	getAggregateFunctions() Return the aggregate functions useds for every attribute of the feature.
java.lang.String[]	getAttributeNames() Returns the names of the attributes to load from each Feature.
java.lang.String[]	getConstantsAttributeNames() Returns the names of the attributes that are constants in each Feature.
FeatureQuery	getCopy()
Expression	getExpressionFilter() Return the Expression associated to the filter.
FeatureExtraColumns	getExtraColumn()
FeatureExtraColumns	getExtraColumns() Extra local columns to the query.
java.lang.String	getFeatureTypeId() Returns the FeatureType id of the Features to load.
Evaluator	getFilter() Returns the filter to apply to the Features to load.
java.util.List<java.lang.String>	getGroupByColumns() Return the names of attributes for group the features.
long	getLimit() Returns the maximum number of elements to return with this query.
FeatureQueryOrder	getOrder() Returns the order of the Features to load.
long	getPageSize() Returns the load page size, as the number of elements to be retrieved in block by the data source.
MutableSymbolTable	getSymbolTable()
boolean	hasAggregateFunctions()
boolean	hasAttributeNames() Return true if has set attribute names
boolean	hasConstantsAttributeNames() Return true if has set constants attribute names
boolean	hasFilter() Returns if a filter has been defined for the query.
boolean	hasGroupByColumns()
boolean	hasLimit()
boolean	hasOrder() Returns if an order has been set for the elements returned by the query.
boolean	isAggregate(java.lang.String name)
boolean	isAGroupByColumn(java.lang.String name)
boolean	isUseSubquery() Returns true if a subquery should be used.
void	removeAggregateFunction(java.lang.String colname)
void	removeGroupByColumn(java.lang.String colname)
void	retrievesAllAttributes()
void	setAttributeNames(java.lang.String[] attributeNames) Sets the names of the attributes to load from each Feature.
void	setConstantsAttributeNames(java.lang.String[] attributeNames) Set of attribute names to be treated as constants for each Feature.
void	setFeatureType(FeatureType featureType) Sets the FeatureType of the Features to load.
void	setFeatureTypeId(java.lang.String featureTypeId) Sets the FeatureType id of the Features to load.
void	setFilter(Evaluator filter) Sets the filter to apply to the Features to load.
void	setFilter(Expression filter)
void	setFilter(java.lang.String filter)
void	setLimit(long limit) Sets the maximum number of elements to return with this query.
void	setOrder(FeatureQueryOrder order) Sets the order of the Features to load.
void	setPageSize(long pageSize) Sets the load page size, as the number of elements to be retrieved in block by the data source.
void	setSymbolTable(MutableSymbolTable symbolTable)
void	setUseSubquery(boolean useSubquery) Indicates whether to use a subquery or not in case the connection has an sql indicated.
void	setVar(java.lang.String name, java.lang.Object value) Set a variable in the symbol table associated to this searchPanel.

Methods inherited from interface org.gvsig.fmap.dal.DataQuery

getQueryParameter, getScale, setQueryParameter, setScale

Methods inherited from interface org.gvsig.tools.persistence.Persistent

loadFromState, saveToState

Methods inherited from interface org.gvsig.tools.lang.Cloneable

clone, cloneQuietly, cloneQuietly

Methods inherited from interface org.gvsig.json.SupportFromJson

fromJson

Methods inherited from interface org.gvsig.json.SupportToJson

toJson, toJson, toJsonBuilder, toJsonBuilder

Field Detail

NO_LIMIT

static final int NO_LIMIT

See Also:

Constant Field Values

Method Detail

getAttributeNames

java.lang.String[] getAttributeNames()

Returns the names of the attributes to load from each Feature.

Returns:

the attribute names to load

setAttributeNames

void setAttributeNames(java.lang.String[] attributeNames)

Sets the names of the attributes to load from each Feature.

Parameters:

attributeNames - the attribute names to load

retrievesAllAttributes

void retrievesAllAttributes()

addAttributeName

void addAttributeName(java.lang.String attributeName)

Adds the name of an attribute that has to be used to load each Feature.

Parameters:

attributeName - the attribute name to load

addPrimaryKeyAttributeNames

void addPrimaryKeyAttributeNames(FeatureStore store)

addEssentialAttributeNames

void addEssentialAttributeNames(FeatureStore store)

hasAttributeNames

boolean hasAttributeNames()

Return true if has set attribute names

Returns:

true if has attribute names, otherwise false

clearAttributeNames

void clearAttributeNames()

Remove all the attribute names specifieds.

getConstantsAttributeNames

java.lang.String[] getConstantsAttributeNames()

Returns the names of the attributes that are constants in each Feature. These attributes will not be charged.

Returns:

the attribute names that are constant

setConstantsAttributeNames

void setConstantsAttributeNames(java.lang.String[] attributeNames)

Set of attribute names to be treated as constants for each Feature.

Parameters:

attributeNames - the attribute names to be constants

addConstantAttributeName

void addConstantAttributeName(java.lang.String attributeName)

Add an attribute name that will be treated as constant for each Feature.

Parameters:

attributeName - the attribute name to be treated as constant

hasConstantsAttributeNames

boolean hasConstantsAttributeNames()

Return true if has set constants attribute names

Returns:

true if has constants attribute names, otherwise false

clearConstantsAttributeNames

void clearConstantsAttributeNames()

Remove all the names specified as constants attributes.

setFeatureType

void setFeatureType(FeatureType featureType)

Sets the FeatureType of the Features to load. It may be used as an alternative way to set a subset of the list of attribute names to load, by creating a sub-FeatureType.

Parameters:

featureType - the feature type of the data to load

getFeatureTypeId

java.lang.String getFeatureTypeId()

Returns the FeatureType id of the Features to load.

Returns:

the FeatureType id of the Features to load

setFeatureTypeId

void setFeatureTypeId(java.lang.String featureTypeId)

Sets the FeatureType id of the Features to load. This way all Feature attributes will be loaded.

Parameters:

featureTypeId - the FeatureType id of the Features to load

getFilter

Evaluator getFilter()

Returns the filter to apply to the Features to load.

Returns:

the filter

getExpressionFilter

Expression getExpressionFilter()

Return the Expression associated to the filter. If the current filter is not an Expression, return null.

Returns:

the expression of the filter.

setFilter

void setFilter(Evaluator filter)

Sets the filter to apply to the Features to load.

Parameters:

filter - the filter to apply to the Features to load

setFilter

void setFilter(Expression filter)

setFilter

void setFilter(java.lang.String filter)

addFilter

void addFilter(Evaluator filter)

Adds a filter to apply to the Features to load. A query can have more that one filter and all of them are applied when the query is applied. If filter is null do nothing.

Parameters:

filter - a filter to apply to the Features to load

addFilter

void addFilter(Expression filter)

addFilter

void addFilter(java.lang.String filter)

clearFilter

void clearFilter()

hasFilter

boolean hasFilter()

Returns if a filter has been defined for the query.

Returns:

if a filter has been defined for the query

getOrder

FeatureQueryOrder getOrder()

Returns the order of the Features to load.

Returns:

the order of the Features to load

setOrder

void setOrder(FeatureQueryOrder order)

Sets the order of the Features to load.

Parameters:

order - the order of the Features to load

hasOrder

boolean hasOrder()

Returns if an order has been set for the elements returned by the query.

Returns:

if an order has been set for the elements returned by the query

getCopy

FeatureQuery getCopy()

Returns:

@deprecated to be removed in gvSIG 2.0

See Also:

Cloneable.clone()

getLimit

long getLimit()

Returns the maximum number of elements to return with this query.

NOTE: this value may be ignored by the underlying data source, or only used as a hint, so don't rely on it being used, as you may actually get more values than the limit.

Returns:

the maximum number of elements to return with this query

setLimit

void setLimit(long limit)

Sets the maximum number of elements to return with this query.

NOTE: this value may be ignored by the underlying data source, or only used as a hint, so don't rely on it being used, as you may actually get more values than the limit.

Parameters:

limit - the maximum number of elements to return with this query

clearLimit

void clearLimit()

getPageSize

long getPageSize()

Returns the load page size, as the number of elements to be retrieved in block by the data source. This value is only used as a hint to the underlying data source, as a way to tell how many Features may be read in a block.

Returns:

the load page size

setPageSize

void setPageSize(long pageSize)

Sets the load page size, as the number of elements to be retrieved in block by the data source. This value is only used as a hint to the underlying data source, as a way to tell how many Features may be read in a block.

Parameters:

pageSize - the load page size

isUseSubquery

boolean isUseSubquery()

Returns true if a subquery should be used. It will only take effect when the sql perameter of the connection has a value.

Returns:

setUseSubquery

void setUseSubquery(boolean useSubquery)

Indicates whether to use a subquery or not in case the connection has an sql indicated. This flag will have no effect if the "sql" parameter in the connection has not been specified. By default it will be true and whenever an sql has been indicated in the connection, a subquery will be used to access the data. If false is assigned, the sql should return, in the same order, the rows required by the FeatureType of the store.

Parameters:

useSubquery -

getGroupByColumns

java.util.List<java.lang.String> getGroupByColumns()

Return the names of attributes for group the features.

Returns:

the list of names to group features.

removeGroupByColumn

void removeGroupByColumn(java.lang.String colname)

isAGroupByColumn

boolean isAGroupByColumn(java.lang.String name)

hasGroupByColumns

boolean hasGroupByColumns()

getAggregateFunctions

java.util.Map<java.lang.String,java.lang.String> getAggregateFunctions()

Return the aggregate functions useds for every attribute of the feature. The map is indexed by the name of the attribute and contains the aggregate functions used by each attribute.

Returns:

a Map with the aggregate function by attribute

removeAggregateFunction

void removeAggregateFunction(java.lang.String colname)

getAggregateFunction

java.lang.String getAggregateFunction(java.lang.String name)

addAggregate

void addAggregate(java.lang.String funcName,
                  java.lang.String columnName)

getAggregate

@Deprecated
java.lang.String getAggregate(java.lang.String name)

Deprecated.

getAggregate

java.lang.String getAggregate(java.lang.String tableName,
                              java.lang.String name)

isAggregate

boolean isAggregate(java.lang.String name)

hasAggregateFunctions

boolean hasAggregateFunctions()

copyFrom

void copyFrom(FeatureQuery query)

getExtraColumn

FeatureExtraColumns getExtraColumn()

getExtraColumns

FeatureExtraColumns getExtraColumns()

Extra local columns to the query. It will never be null.

Returns:

getSymbolTable

MutableSymbolTable getSymbolTable()

setSymbolTable

void setSymbolTable(MutableSymbolTable symbolTable)

setVar

void setVar(java.lang.String name,
            java.lang.Object value)

Set a variable in the symbol table associated to this searchPanel.

Parameters:

name -

value -

hasLimit

boolean hasLimit()