org.eclipse.equinox.p2.metadata.expression

Interface IContextExpression<T>

All Superinterfaces:

IExpression

All Known Implementing Classes:

ContextExpression

public interface IContextExpression<T>
extends IExpression

This is an expression that will need access to the global variable everything.

Since:

2.0

Field Summary

Fields inherited from interface org.eclipse.equinox.p2.metadata.expression.IExpression

TYPE_ALL, TYPE_AND, TYPE_ARRAY, TYPE_ASSIGNMENT, TYPE_AT, TYPE_COLLECT, TYPE_CONDITION, TYPE_EQUALS, TYPE_EXISTS, TYPE_FIRST, TYPE_FLATTEN, TYPE_FUNCTION, TYPE_GREATER, TYPE_GREATER_EQUAL, TYPE_INTERSECT, TYPE_LAMBDA, TYPE_LATEST, TYPE_LESS, TYPE_LESS_EQUAL, TYPE_LIMIT, TYPE_LITERAL, TYPE_MATCHES, TYPE_MEMBER, TYPE_NOT, TYPE_NOT_EQUALS, TYPE_OR, TYPE_PARAMETER, TYPE_PIPE, TYPE_SELECT, TYPE_TRAVERSE, TYPE_UNION, TYPE_UNIQUE, TYPE_VARIABLE

Method Summary

Modifier and Type	Method and Description
IEvaluationContext	createContext(java.lang.Class<? extends T> elementClass, IIndexProvider<T> indexProvider) Creates a new context to be passed to a subsequent evaluation.
IEvaluationContext	createContext(java.lang.Class<? extends T> elementClass, java.util.Iterator<T> everything) Creates a new context to be passed to a subsequent evaluation.
java.lang.Object[]	getParameters() Returns the parameters that this context expression was created with.
java.util.Iterator<T>	iterator(IEvaluationContext context) Evaluate the expression and return the expected collection result as an iterator

Methods inherited from interface org.eclipse.equinox.p2.metadata.expression.IExpression

accept, evaluate, getExpressionType, toLDAPString, toString

Method Detail

createContext

IEvaluationContext createContext(java.lang.Class<? extends T> elementClass,
                                 IIndexProvider<T> indexProvider)

Creates a new context to be passed to a subsequent evaluation. The context will have the variable 'everything' set to an expression that represents the everything iterator filtered for instances of elementClass.

The values of the iterator will be copied if necessary (when everything is referenced more then once).

Parameters:

elementClass - the class of the iterator elements

indexProvider - The index provider that represents all queried material.

Returns:

A new evaluation context.

createContext

IEvaluationContext createContext(java.lang.Class<? extends T> elementClass,
                                 java.util.Iterator<T> everything)

Creates a new context to be passed to a subsequent evaluation. The context will have the variable 'everything' set to an expression that represents the everything iterator filtered for instances of elementClass.

The values of the iterator will be copied if necessary (when everything is referenced more then once).

Parameters:

elementClass - the class of the iterator elements

everything - The iterator that represents all queried material.

Returns:

A new evaluation context.

getParameters

java.lang.Object[] getParameters()

Returns the parameters that this context expression was created with.

Returns:

An array of parameters, possibly empty but never null.

iterator

java.util.Iterator<T> iterator(IEvaluationContext context)

Evaluate the expression and return the expected collection result as an iterator

Parameters:

context - The evaluation context

Returns:

The result of the evaluation.