JarCastingJava8 Predicates
The intention of this project is to improve readability of equality and relational operators (< > <= >= == !=) using predefined Predicates. It also contains a Predicate interface with then(), orElse() and elseIf() to replace if-then and if-then-else statements.
mvn
<dependency>
<groupId>com.github.puddingspudding</groupId>
<artifactId>predicates</artifactId>
<version>0.4</version>
</dependency>
Predicates
- isEqualTo { a == b }
- isNotEqualTo { a != b }
- isBiggerThan { a > b }
- isSmallerThan { a < b }
- isEqualOrBiggerThan { a >= b }
- isEqualOrSmallerThan { a <= b }
- isInRange { a <= x && x <= b }
- isNotInRage { x < a && b < x }
- isNegative { a < 0 }
- isPositive { a > 0 }
- isEven { x % 2 == 0 }
- isOdd { x % 2 != 0 }
Examples
java.util.function.Predicate
import java.util.function.Predicate;
import static com.github.puddingspudding.IntegerPredicates.*;
import static com.github.puddingspudding.LongPredicates.*;
// isEqualTo
Predicate<Integer> isEqualToOne = isEqualTo(1);
if (isEqualToOne.test(1)) {
// do something
}
// isNotEqualTo
Predicate<Integer> isNotEqualToOne = isNotEqualTo(1);
if (isNotEqualToOne.test(2)) {
// do something
}
// ...
if (isBiggerThan(10).or(isSmallerThan(-10)).test(x))) {
// x is awesome
// or use isNotInRange(-10).apply(10).test(x)
}
Stream.of(1,2,3,4,5,6)
.filter(isBiggerThan(3))
.collect(Collectors.toList());
// [4, 5, 6]