org.apache.qpid.filter

Class ComparisonExpression<T>

java.lang.Object

org.apache.qpid.filter.BinaryExpression<T>

org.apache.qpid.filter.ComparisonExpression<T>

All Implemented Interfaces:

BooleanExpression<T>, Expression<T>

public abstract class ComparisonExpression<T>
extends BinaryExpression<T>
implements BooleanExpression<T>

A filter performing a comparison of two objects

Constructor Summary

Constructors

Constructor and Description
ComparisonExpression(Expression<T> left, Expression<T> right)

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract boolean	asBoolean(int answer)
static <E> void	checkEqualOperand(Expression<E> expr) Validates that the expression can be used in == or <> expression.
static <E> void	checkLessThanOperand(Expression<E> expr) Only Numeric expressions can be used in >, >=, < or <= expressions.
protected Boolean	compare(Comparable lv, Comparable rv)
static <E> BooleanExpression<E>	createBetween(Expression<E> value, Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createEqual(Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createGreaterThan(Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createGreaterThanEqual(Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createInFilter(Expression<E> left, List<?> elements, boolean allowNonJms)
static <E> BooleanExpression<E>	createIsNotNull(Expression<E> left)
static <E> BooleanExpression<E>	createIsNull(Expression<E> left)
static <E> BooleanExpression<E>	createLessThan(Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createLessThanEqual(Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createLike(Expression<E> left, String right, String escape)
static <E> BooleanExpression<E>	createNotBetween(Expression<E> value, Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createNotEqual(Expression<E> left, Expression<E> right)
static <E> BooleanExpression<E>	createNotInFilter(Expression<E> left, List<?> elements, boolean allowNonJms)
static <E> BooleanExpression<E>	createNotLike(Expression<E> left, String right, String escape)
Object	evaluate(T message)
boolean	matches(T message)

Methods inherited from class org.apache.qpid.filter.BinaryExpression

equals, getExpressionSymbol, getLeft, getRight, hashCode, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ComparisonExpression

public ComparisonExpression(Expression<T> left,
                    Expression<T> right)

Method Detail

createBetween

public static <E> BooleanExpression<E> createBetween(Expression<E> value,
                                     Expression<E> left,
                                     Expression<E> right)

createNotBetween

public static <E> BooleanExpression<E> createNotBetween(Expression<E> value,
                                        Expression<E> left,
                                        Expression<E> right)

createLike

public static <E> BooleanExpression<E> createLike(Expression<E> left,
                                  String right,
                                  String escape)

createNotLike

public static <E> BooleanExpression<E> createNotLike(Expression<E> left,
                                     String right,
                                     String escape)

createInFilter

public static <E> BooleanExpression<E> createInFilter(Expression<E> left,
                                      List<?> elements,
                                      boolean allowNonJms)

createNotInFilter

public static <E> BooleanExpression<E> createNotInFilter(Expression<E> left,
                                         List<?> elements,
                                         boolean allowNonJms)

createIsNull

public static <E> BooleanExpression<E> createIsNull(Expression<E> left)

createIsNotNull

public static <E> BooleanExpression<E> createIsNotNull(Expression<E> left)

createNotEqual

public static <E> BooleanExpression<E> createNotEqual(Expression<E> left,
                                      Expression<E> right)

createEqual

public static <E> BooleanExpression<E> createEqual(Expression<E> left,
                                   Expression<E> right)

createGreaterThan

public static <E> BooleanExpression<E> createGreaterThan(Expression<E> left,
                                         Expression<E> right)

createGreaterThanEqual

public static <E> BooleanExpression<E> createGreaterThanEqual(Expression<E> left,
                                              Expression<E> right)

createLessThan

public static <E> BooleanExpression<E> createLessThan(Expression<E> left,
                                      Expression<E> right)

createLessThanEqual

public static <E> BooleanExpression<E> createLessThanEqual(Expression<E> left,
                                           Expression<E> right)

checkLessThanOperand

public static <E> void checkLessThanOperand(Expression<E> expr)

Only Numeric expressions can be used in >, >=, < or <= expressions.

Parameters:

expr - expression to check

checkEqualOperand

public static <E> void checkEqualOperand(Expression<E> expr)

Validates that the expression can be used in == or <> expression. Cannot not be NULL TRUE or FALSE literals.

Parameters:

expr - expression to check

evaluate

public Object evaluate(T message)

Specified by:

evaluate in interface Expression<T>

Parameters:

message - object to evaluate

Returns:

the value of this expression

compare

protected Boolean compare(Comparable lv,
              Comparable rv)

asBoolean

protected abstract boolean asBoolean(int answer)

matches

public boolean matches(T message)

Specified by:

matches in interface BooleanExpression<T>

Parameters:

message - object to match

Returns:

true if the expression evaluates to Boolean.TRUE.