org.apache.olingo.odata2.core.uri.expression

Class OrderByExpressionImpl

java.lang.Object

org.apache.olingo.odata2.core.uri.expression.OrderByExpressionImpl

All Implemented Interfaces:

CommonExpression, OrderByExpression, Visitable

public class OrderByExpressionImpl
extends Object
implements OrderByExpression

Constructor Summary

Constructors

Constructor and Description
OrderByExpressionImpl(String orderbyString)

Method Summary

Modifier and Type	Method and Description
Object	accept(ExpressionVisitor visitor) Method Visitable.accept(ExpressionVisitor) is called when traversing the expression tree.
void	addOrder(OrderExpression orderNode)
EdmType	getEdmType()
String	getExpressionString()
ExpressionKind	getKind()
List<OrderExpression>	getOrders()
int	getOrdersCount()
String	getUriLiteral() Returns the URI literal which lead to the creation of this expression.
CommonExpression	setEdmType(EdmType edmType) Set the edmType of this expression node

Methods inherited from class java.lang.Object

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

Constructor Detail

OrderByExpressionImpl

public OrderByExpressionImpl(String orderbyString)

Method Detail

getExpressionString

public String getExpressionString()

Specified by:

getExpressionString in interface OrderByExpression

Returns:

Returns the $filter expression string used to build the expression tree

getOrders

public List<OrderExpression> getOrders()

Specified by:

getOrders in interface OrderByExpression

Returns:

Returns a ordered list of order expressions contained in the $orderby expression string

For example: The orderby expression build from "$orderby=name asc, age desc" would contain to order expression.

getOrdersCount

public int getOrdersCount()

Specified by:

getOrdersCount in interface OrderByExpression

Returns:

Returns the count of order expressions contained in the $orderby expression string

addOrder

public void addOrder(OrderExpression orderNode)

getKind

public ExpressionKind getKind()

Specified by:

getKind in interface CommonExpression

Returns:

Kind of this expression

See Also:

ExpressionKind

getEdmType

public EdmType getEdmType()

Specified by:

getEdmType in interface CommonExpression

Returns:

The return type of the value represented with this expression. For example the CommonExpression.getEdmType() method for an expression representing the "concat" method will return always "Edm.String".

This type information is set while parsing the $filter or $orderby expressions and used to do a first validation of the expression. For calculating operators like "add, sub, mul" this type information is purely based on input and output types of the operator as defined in the OData specification. So for $filter=2 add 7 the CommonExpression.getEdmType() method of the binary expression will return Edm.Byte and not Edm.Int16 because the parser performs no real addition.

However, the application may change this type while evaluating the expression tree.

setEdmType

public CommonExpression setEdmType(EdmType edmType)

Description copied from interface: CommonExpression

Set the edmType of this expression node

Specified by:

setEdmType in interface CommonExpression

Parameters:

edmType - Type to be set

Returns:

A self reference for method chaining"

getUriLiteral

public String getUriLiteral()

Description copied from interface: CommonExpression

Returns the URI literal which lead to the creation of this expression.

Specified by:

getUriLiteral in interface CommonExpression

Returns:

URI literal

accept

public Object accept(ExpressionVisitor visitor)
              throws ExceptionVisitExpression,
                     ODataApplicationException

Description copied from interface: Visitable

Method Visitable.accept(ExpressionVisitor) is called when traversing the expression tree. This method is invoked on each expression used as node in an expression tree. The implementations should behave as follows:

Call accept on all sub nodes and store the returned Objects Call the appropriate method on the ExpressionVisitor instance and provide the stored objects to that instance Return the object which should be passed to the processing algorithm of the parent expression node

Specified by:

accept in interface Visitable

Parameters:

visitor - Object ( implementing ExpressionVisitor) whose methods are called during traversing a expression node of the expression tree.

Returns:

Object which should be passed to the processing algorithm of the parent expression node

Throws:

ExceptionVisitExpression - Exception occurred the OData library while traversing the tree

ODataApplicationException - Exception thrown by the application who implemented the visitor