org.apache.stanbol.entityhub.servicesapi.query
Interface FieldQuery

All Superinterfaces:

Cloneable, Iterable<Map.Entry<String,Constraint>>, Query

public interface FieldQuery
extends Query, Iterable<Map.Entry<String,Constraint>>, Cloneable

Simple query interface that allows to search for representations based on fields and there values.

Currently it is only possible to set a single constraint per field. Therefore it is not possible to combine an range constraint with an language constraint. e.g. searching for all labels form a-f in a list of given languages. TODO: This shortcoming needs to be reevaluated. The intension was to ease the implementation and the usage of this interface. TODO: Implementation need to be able to throw UnsupportedConstraintExceptions for specific combinations of Constraints e.g. Regex or case insensitive ... TODO: Would be nice if an Implementation could also announce the list of supported constraints (e.g. via Capability levels ...)

Author:

Rupert Westenthaler

Field Summary

static String

TYPE The value used as result for Query.getQueryType() of this query type.

Method Summary

void	addSelectedField(String field) Adds Fields to be selected by this Query
void	addSelectedFields(Collection<String> fields) Adds Fields to be selected by this Query
FieldQuery	clone() Clones the FieldQuery
<T extends FieldQuery> T	copyTo(T copyTo) Copies the state of this instance to the parsed one
Constraint	getConstraint(String field) Getter for the Constraint of a field
Set<Map.Entry<String,Constraint>>	getConstraints() Getter for the unmodifiable list of query elements for the given Path.
Set<String>	getSelectedFields() Unmodifiable set with all the fields to be selected by this query
boolean	isConstrained(String field) Checks if there is a constraint for the given field
void	removeAllConstraints() Removes all constraints form the query
void	removeAllSelectedFields() Removes all selected fields
void	removeConstraint(String field) Removes the constraint for the parse field
void	removeSelectedField(String fields) Removes Fields to be selected by this Query
void	removeSelectedFields(Collection<String> fields) Removes Fields to be selected by this Query
void	setConstraint(String field, Constraint constraint) Sets/replaces the constraint for a field of the representation.

Methods inherited from interface org.apache.stanbol.entityhub.servicesapi.query.Query

getLimit, getOffset, getQueryType, setLimit, setOffset

Methods inherited from interface java.lang.Iterable

iterator

Field Detail

TYPE

static final String TYPE

The value used as result for Query.getQueryType() of this query type.

See Also:

Constant Field Values

Method Detail

addSelectedField

void addSelectedField(String field)

Adds Fields to be selected by this Query

Parameters:

fields - the fields to be selected by this query

addSelectedFields

void addSelectedFields(Collection<String> fields)

Adds Fields to be selected by this Query

Parameters:

fields - the fields to be selected by this query

removeSelectedField

void removeSelectedField(String fields)

Removes Fields to be selected by this Query

Parameters:

fields - the fields to be selected by this query

removeSelectedFields

void removeSelectedFields(Collection<String> fields)

Removes Fields to be selected by this Query

Parameters:

fields - the fields to be selected by this query

getSelectedFields

Set<String> getSelectedFields()

Unmodifiable set with all the fields to be selected by this query

Returns:

the fields to be selected by this query

setConstraint

void setConstraint(String field,
                   Constraint constraint)

Sets/replaces the constraint for a field of the representation. If null is parsed as constraint this method removes any existing constraint for the field

Parameters:

field - the field

constraint - the Constraint

removeConstraint

void removeConstraint(String field)

Removes the constraint for the parse field

Parameters:

field -

isConstrained

boolean isConstrained(String field)

Checks if there is a constraint for the given field

Parameters:

field - the field

Returns:

the state

getConstraint

Constraint getConstraint(String field)

Getter for the Constraint of a field

Parameters:

field - the field

Returns:

the constraint or null if none is defined.

getConstraints

Set<Map.Entry<String,Constraint>> getConstraints()

Getter for the unmodifiable list of query elements for the given Path. Use the add/remove constraint methods to change query elements for an path

Parameters:

path - the path

Returns:

the list of query elements for a path

removeAllConstraints

void removeAllConstraints()

Removes all constraints form the query

removeAllSelectedFields

void removeAllSelectedFields()

Removes all selected fields

copyTo

<T extends FieldQuery> T copyTo(T copyTo)

Copies the state of this instance to the parsed one

Type Parameters:

T - the FieldQuery implementation

Parameters:

copyTo - the instance to copy the state

Returns:

the parsed instance with the exact same state as this one

clone

FieldQuery clone()

Clones the FieldQuery

Specified by:

clone in interface Query

Returns:

the clone