org.eclipse.equinox.internal.p2.metadata.expression

Class MatchExpression<T>

java.lang.Object

org.eclipse.equinox.internal.p2.metadata.expression.Expression

org.eclipse.equinox.internal.p2.metadata.expression.Unary

org.eclipse.equinox.internal.p2.metadata.expression.MatchExpression<T>

All Implemented Interfaces:

java.lang.Comparable<Expression>, IExpressionConstants, IExpression, IMatchExpression<T>

public class MatchExpression<T>
extends Unary
implements IMatchExpression<T>

The MatchExpression is a wrapper for an IExpression that is expected to return a boolean value. The wrapper provides the evaluation context needed to evaluate the expression.

Nested Class Summary

Nested classes/interfaces inherited from class org.eclipse.equinox.internal.p2.metadata.expression.Expression

Expression.VariableFinder

Field Summary

Fields inherited from class org.eclipse.equinox.internal.p2.metadata.expression.Unary

operand

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

Fields inherited from interface org.eclipse.equinox.internal.p2.metadata.expression.IExpressionConstants

KEYWORD_ALL, KEYWORD_BOOLEAN, KEYWORD_CLASS, KEYWORD_COLLECT, KEYWORD_EXISTS, KEYWORD_FALSE, KEYWORD_FILTER, KEYWORD_FIRST, KEYWORD_FLATTEN, KEYWORD_INTERSECT, KEYWORD_IQUERY, KEYWORD_LATEST, KEYWORD_LIMIT, KEYWORD_LOCALIZED_KEYS, KEYWORD_LOCALIZED_MAP, KEYWORD_LOCALIZED_PROPERTY, KEYWORD_NULL, KEYWORD_RANGE, KEYWORD_SATISFIES_ALL, KEYWORD_SATISFIES_ANY, KEYWORD_SELECT, KEYWORD_SET, KEYWORD_TRAVERSE, KEYWORD_TRUE, KEYWORD_UNION, KEYWORD_UNIQUE, KEYWORD_VERSION, OPERATOR_AND, OPERATOR_ARRAY, OPERATOR_ASSIGN, OPERATOR_AT, OPERATOR_EACH, OPERATOR_ELSE, OPERATOR_EQUALS, OPERATOR_GT, OPERATOR_GT_EQUAL, OPERATOR_IF, OPERATOR_LT, OPERATOR_LT_EQUAL, OPERATOR_MATCHES, OPERATOR_MEMBER, OPERATOR_NOT, OPERATOR_NOT_EQUALS, OPERATOR_OR, OPERATOR_PARAMETER, PRIORITY_AND, PRIORITY_ASSIGNMENT, PRIORITY_BINARY, PRIORITY_COLLECTION, PRIORITY_COMMA, PRIORITY_CONDITION, PRIORITY_FUNCTION, PRIORITY_LAMBDA, PRIORITY_LITERAL, PRIORITY_MAX, PRIORITY_MEMBER, PRIORITY_NOT, PRIORITY_OR, PRIORITY_VARIABLE, VARIABLE_EVERYTHING, VARIABLE_THIS

Method Summary

Modifier and Type	Method and Description
boolean	accept(IExpressionVisitor visitor) Let the visitor visit this instance and all expressions that this instance contains.
IEvaluationContext	createContext() Creates a new context to be passed to repeated subsequent evaluations.
boolean	equals(java.lang.Object o)
java.lang.Object	evaluate(IEvaluationContext context) Evaluate this expression with given context and variables.
int	getExpressionType() Returns the expression type (see TYPE_xxx constants).
java.lang.String	getOperator()
java.lang.Object[]	getParameters() Returns the parameters that this match expression was created with.
int	getPriority()
int	hashCode()
boolean	isMatch(IEvaluationContext context, T value) This method assigns candidate to the 'this' variable of the context and then evaluates the expression.
boolean	isMatch(T value) This method creates a new evaluation context and assigns the candidate to the 'this' variable of the context and then evaluates the expression.
void	toLDAPString(java.lang.StringBuffer bld) Appends the an LDAP filter representation of this expression to the collector.
void	toString(java.lang.StringBuffer bld, Variable rootVariable)

Methods inherited from class org.eclipse.equinox.internal.p2.metadata.expression.Unary

compareTo, getOperand

Methods inherited from class org.eclipse.equinox.internal.p2.metadata.expression.Expression

appendOperand, assertLength, assertLength, compare, elementsToString, equals, evaluateAsIterator, getIndexCandidateMembers, hashCode, isReferenceTo, needsTranslationSupport, toLDAPString, toString, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

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

toString

Method Detail

accept

public boolean accept(IExpressionVisitor visitor)

Description copied from class: Expression

Let the visitor visit this instance and all expressions that this instance contains.

Specified by:

accept in interface IExpression

Overrides:

accept in class Unary

Parameters:

visitor - The visiting visitor.

Returns:

true if the visitor should continue visiting, false otherwise.

createContext

public IEvaluationContext createContext()

Description copied from interface: IMatchExpression

Creates a new context to be passed to repeated subsequent evaluations. The context will introduce 'this' as an uninitialized variable and make the parameters available.

Specified by:

createContext in interface IMatchExpression<T>

Returns:

A new evaluation context.

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class Unary

evaluate

public java.lang.Object evaluate(IEvaluationContext context)

Description copied from class: Expression

Evaluate this expression with given context and variables.

Specified by:

evaluate in interface IExpression

Overrides:

evaluate in class Unary

Parameters:

context - The evaluation context

Returns:

The result of the evaluation.

getExpressionType

public int getExpressionType()

Description copied from interface: IExpression

Returns the expression type (see TYPE_xxx constants).

Specified by:

getExpressionType in interface IExpression

getOperator

public java.lang.String getOperator()

Specified by:

getOperator in class Expression

getParameters

public java.lang.Object[] getParameters()

Description copied from interface: IMatchExpression

Returns the parameters that this match expression was created with.

Specified by:

getParameters in interface IMatchExpression<T>

Returns:

An array of parameters, possibly empty but never null.

getPriority

public int getPriority()

Specified by:

getPriority in class Expression

hashCode

public int hashCode()

Overrides:

hashCode in class Unary

isMatch

public boolean isMatch(IEvaluationContext context,
                       T value)

Description copied from interface: IMatchExpression

This method assigns candidate to the 'this' variable of the context and then evaluates the expression.

Specified by:

isMatch in interface IMatchExpression<T>

Parameters:

context - A context

value - The object to test.

Returns:

the result of the evaluation.

isMatch

public boolean isMatch(T value)

Description copied from interface: IMatchExpression

This method creates a new evaluation context and assigns the candidate to the 'this' variable of the context and then evaluates the expression. This is essentially a short form for

isMatch(createContext(), candidate)

.

Specified by:

isMatch in interface IMatchExpression<T>

Parameters:

value - The object to test.

Returns:

the result of the evaluation.

toLDAPString

public void toLDAPString(java.lang.StringBuffer bld)

Description copied from interface: IExpression

Appends the an LDAP filter representation of this expression to the collector.

Specified by:

toLDAPString in interface IExpression

Overrides:

toLDAPString in class Expression

toString

public void toString(java.lang.StringBuffer bld,
                     Variable rootVariable)

Overrides:

toString in class Unary