com.querydsl.core.types

Interface Expression<T>

Type Parameters:

T - expression type

All Superinterfaces:

Serializable

All Known Subinterfaces:

ArrayExpression<A,T>, CollectionExpression<T,E>, Constant<T>, EntityPath<T>, ExtendedSubQuery<T>, FactoryExpression<T>, GroupExpression<T,R>, JDOQLQuery<T>, JPQLQuery<T>, ListExpression<E,Q>, MapExpression<K,V>, Operation<T>, ParameterizedExpression<T>, ParamExpression<T>, Path<T>, Predicate, RelationalPath<T>, SubQueryExpression<T>, TemplateExpression<T>, Union<RT>

All Known Implementing Classes:

AbstractGroupExpression, AbstractHibernateQuery, AbstractHibernateSQLQuery, AbstractJDOQuery, AbstractJPAQuery, AbstractJPASQLQuery, AbstractSQLQuery, AbstractSQLQuery, AbstractSQLQuery, ArrayConstructorExpression, ArrayPath, BeanPath, BooleanBuilder, BooleanExpression, BooleanOperation, BooleanPath, BooleanTemplate, Coalesce, CollectionExpressionBase, CollectionOperation, CollectionPath, CollectionPathBase, ComparableEntityPath, ComparableExpression, ComparableExpressionBase, ComparableOperation, ComparablePath, ComparableTemplate, ConstantImpl, ConstructorExpression, CurveExpression, DateExpression, DateOperation, DatePath, DateTemplate, DateTimeExpression, DateTimeOperation, DateTimePath, DateTimeTemplate, DslExpression, DslOperation, DslPath, DslTemplate, EntityPathBase, EnumConversion, EnumExpression, EnumOperation, EnumPath, EnumTemplate, ExpressionBase, FactoryExpressionBase, FactoryExpressionUtils.FactoryExpressionAdapter, FetchableSubQueryBase, GeometryCollectionExpression, GeometryCollectionPath, GeometryExpression, GeometryOperation, GeometryPath, HibernateQuery, HibernateSQLQuery, JDOQuery, JDOSQLQuery, JPAQuery, JPAQueryBase, JPASQLQuery, JTSCurveExpression, JTSGeometryCollectionExpression, JTSGeometryCollectionPath, JTSGeometryExpression, JTSGeometryOperation, JTSGeometryPath, JTSLinearRingExpression, JTSLinearRingPath, JTSLineExpression, JTSLineStringExpression, JTSLineStringOperation, JTSLineStringPath, JTSMultiCurveExpression, JTSMultiLineStringExpression, JTSMultiLineStringPath, JTSMultiPointExpression, JTSMultiPointPath, JTSMultiPolygonExpression, JTSMultiPolygonPath, JTSMultiSurfaceExpression, JTSPointExpression, JTSPointOperation, JTSPointPath, JTSPolygonExpression, JTSPolygonOperation, JTSPolygonPath, JTSSurfaceExpression, LinearRingExpression, LinearRingPath, LineExpression, LineStringExpression, LineStringOperation, LineStringPath, ListPath, LiteralExpression, MapExpressionBase, MapPath, MappingProjection, MixinGroupExpression, MultiCurveExpression, MultiLineStringExpression, MultiLineStringPath, MultiPointExpression, MultiPointPath, MultiPolygonExpression, MultiPolygonPath, MultiSurfaceExpression, MutableExpressionBase, MySQLQuery, NullExpression, NumberConversion, NumberConversions, NumberExpression, NumberOperation, NumberPath, NumberTemplate, OperationImpl, OracleQuery, Param, ParameterizedPathImpl, ParamExpressionImpl, PathBuilder, PathImpl, PhraseElement, PhraseElement, PhraseElement, Point, PointExpression, PointOperation, PointPath, PolygonExpression, PolygonOperation, PolygonPath, PolyhedralSurfaceExpression, PolyhedralSurfacePath, PostgreSQLQuery, PredicateOperation, PredicateTemplate, ProjectableSQLQuery, QBean, QBeans, QList, QMap, QPair, QSpatialRefSys, QTuple, QueryElement, QueryElement, QueryElement, RelationalFunctionCall, RelationalPathBase, RelationalPathSpatial, SetPath, SimpleExpression, SimpleOperation, SimplePath, SimpleTemplate, SQLQuery, SQLServerQuery, StringExpression, StringOperation, StringPath, StringTemplate, SubQueryExpressionImpl, SurfaceExpression, TemplateExpressionImpl, TemporalExpression, TeradataQuery, TermElement, TermElement, TermElement, TimeExpression, TimeOperation, TimePath, TimeTemplate, UnionImpl, WindowFirstLast, WindowFunction, WindowOver, WithinGroup, WithinGroup.OrderBy

public interface Expression<T>
extends Serializable

Expression defines a general typed expression in a Query instance. The generic type parameter is a reference to the type the expression is bound to.

The central Expression subinterfaces are

• Constant - for constants such as Strings, numbers and entity instances
• FactoryExpression - for row based result processing
• Operation - for common supported operations and function calls
• ParamExpression - for bindable query parameters
• Path - for variables, properties and collection member access
• SubQueryExpression - for subqueries
• TemplateExpression - for custom syntax

Author:

tiwe

Method Summary

Modifier and Type	Method and Description
<R,C> R	accept(Visitor<R,C> v, C context) Accept the visitor with the given context
Class<? extends T>	getType() Get the java type for this expression

Method Detail

accept

@Nullable
<R,C> R accept(Visitor<R,C> v,
                         @Nullable
                         C context)

Accept the visitor with the given context

Type Parameters:

R - return type

C - context type

Parameters:

v - visitor

context - context of visit

Returns:

result of visit

getType

Class<? extends T> getType()

Get the java type for this expression

Returns:

type of expression