Range Class | Guava | Java

Guava’s Range represents an interval, for example, a < range < b. Here range includes any value between a and b, called endpoints which form the boundary. Any value between the boundary is a contiguous span of values of type Comparable.

Declaration : The declaration for com.google.common.collect.Range<C> class is :

@GwtCompatible
public final class Range<C extends Comparable>
   extends Object
      implements Predicate<C>, Serializable

Each end of the range may be bounded or unbounded. If bounded, there is an associated endpoint value. If not it will be treated as infinity. A range can be further defined as either open or closed based whether the range is exclusive or inclusive of the endpoints.

• open(a, b) : It represents a < range < b, and in notation form, (a, b).
• closed(a, b) : It represents a <= range <= b, and in notation form, [a, b].
• openClosed(a, b) : It represents a < range <= b, and in notation form, (a, b].
• closedOpen(a, b) : It represents a <= range < b, and in notation form, [a, b).
• greaterThan(a) : It represents range > a, and in notation form, (a..+inf).
• atLeast(a, b) : It represents range >= a, and in notation form, [a..+inf).
• lessThan(a, b) : It represents range < b, and in notation form, (-inf..b).
• atMost(a, b) : It represents range <= b, and in notation form, (-inf..b].
• all() : It represents -inf < range < +inf, and in notation form, (-inf..+inf).

Below given are some methods provided by Range Class of Guava :

Note : When both endpoints exist, the upper endpoint may not be less than the lower. The endpoints may be equal only if at least one of the bounds is closed :

• [a..a] : a singleton range.
• [a..a) or (a..a] : empty ranges, also valid.
• (a..a) : invalid, an exception will be thrown.

Some other methods provided by Range Class of Guava are :

Exceptions :

• open : IllegalArgumentException if lower is greater than or equal to upper.
• closed : IllegalArgumentException if lower is greater than upper.
• closedOpen: IllegalArgumentException if lower is greater than upper.
• openClosed : IllegalArgumentException if lower is greater than upper.
• range : IllegalArgumentException if lower is greater than upper.
• encloseAll : ClassCastException if the parameters are not mutually comparable, NoSuchElementException if values is empty, NullPointerException if any of values is null.
• lowerEndpoint : IllegalStateException if this range is unbounded below (that is, hasLowerBound() returns false).
• lowerBoundType : IllegalStateException if this range is unbounded below (that is, hasLowerBound() returns false).
• upperEndpoint : IllegalStateException if this range is unbounded above (that is, hasUpperBound() returns false).
• upperBoundType : IllegalStateException if this range is unbounded above (that is, hasUpperBound() returns false).
• intersection : IllegalArgumentException if isConnected(connectedRange) is false.

Below given are some examples to understand the implementation in a better way :
Example 1 :

// Java code to show implementation
// of Range class of Guava
import com.google.common.collect.Range;

class GFG {

    // Driver code
    public static void main(String[] args)
    {

        // Taking range (1, 5)
        // Note that here 1 and 5 are not included
        Range<Integer> range = Range.open(1, 5);

        // Checking if range contains 1 or not
        System.out.println(range.contains(1));

        // Checking if range contains 2 or not
        System.out.println(range.contains(2));

        // Checking if range contains 3 or not
        System.out.println(range.contains(3));

        // Checking if range contains 4 or not
        System.out.println(range.contains(4));
    }
}

Output :

false
true
true
true

Example 2 :

// Java code to show implementation
// of Range class of Guava
import com.google.common.collect.Range;

class GFG {

    // Driver code
    public static void main(String[] args)
    {

        // Taking range [1, 5]
        // Note that here 1 and 5 are included
        Range<Integer> range = Range.closed(1, 5);

        // Checking if range contains 1 or not
        System.out.println(range.contains(1));

        // Checking if range contains 2 or not
        System.out.println(range.contains(2));

        // Checking if range contains 3 or not
        System.out.println(range.contains(3));

        // Checking if range contains 5 or not
        System.out.println(range.contains(5));
    }
}

Output :

true
true
true
true

Example 3 :

// Java code to show implementation
// of Range class of Guava
import com.google.common.collect.Range;

class GFG {

    // Driver code
    public static void main(String[] args)
    {

        // Taking range (2, +inf)
        // Note that numbers less than equal to 2
        // are not included
        Range<Integer> range = Range.greaterThan(2);

        // Checking if range contains 1 or not
        System.out.println(range.contains(1));

        // Checking if range contains 2 or not
        System.out.println(range.contains(2));

        // Checking if range contains 130 or not
        System.out.println(range.contains(130));

        // Checking if range contains 500 or not
        System.out.println(range.contains(500));
    }
}

Output :

false
false
true
true

Example 4 :

// Java code to show implementation
// of Range class of Guava
import com.google.common.collect.Range;

class GFG {

    // Driver code
    public static void main(String[] args)
    {

        // Taking range (-inf, 2]
        // Note that only numbers less than equal to 2
        // are included
        Range<Integer> range = Range.atMost(2);

        // Checking if range contains 1 or not
        System.out.println(range.contains(1));

        // Checking if range contains 2 or not
        System.out.println(range.contains(2));

        // Checking if range contains -1 or not
        System.out.println(range.contains(-1));

        // Checking if range contains 5 or not
        System.out.println(range.contains(5));
    }
}

Output :

true
true
true
false