Guava - Range Class


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Range represents an interval or a sequence. It is used to get a set of numbers/ strings lying in a particular range.

Class Declaration

Following is the declaration for com.google.common.collect.Range<C> class:

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

Methods

Sr.No Method & Description
1 static <C extends Comparable<?>> Range<C> all()

Returns a range that contains every value of type C.

2 boolean apply(C input)Deprecated.

Provided only to satisfy the Predicate interface; use contains(C) instead.

3 static <C extends Comparable<?>> Range<C> atLeast(C endpoint)

Returns a range that contains all values greater than or equal to endpoint.

4 static <C extends Comparable<?>> Range<C> atMost(C endpoint)

Returns a range that contains all values less than or equal to endpoint.

5 Range<C> canonical(DiscreteDomain<C> domain)

Returns the canonical form of this range in the given domain.

6 static <C extends Comparable<?>> Range<C> closed(C lower, C upper)

Returns a range that contains all values greater than or equal to lower and less than or equal to upper.

7 static <C extends Comparable<?>> Range<C> closedOpen(C lower, C upper)

Returns a range that contains all values greater than or equal to lower and strictly less than upper.

8 boolean contains(C value)

Returns true if value is within the bounds of this range.

9 boolean containsAll(Iterable<? extends C> values)

Returns true if every element in values is contained in this range.

10 static <C extends Comparable<?>> Range<C> downTo(C endpoint, BoundType boundType)

Returns a range from the given endpoint, which may be either inclusive (closed) or exclusive (open), with no upper bound.

11 static <C extends Comparable<?>> Range<C> encloseAll(Iterable<C> values)

Returns the minimal range that contains all of the given values.

12 boolean encloses(Range<C> other)

Returns true if the bounds of other do not extend outside the bounds of this range.

13 boolean equals(Object object)

Returns true if object is a range having the same endpoints and bound types as this range.

14 static <C extends Comparable<?>> Range<C> greaterThan(C endpoint)

Returns a range that contains all values strictly greater than endpoint.

15 int hashCode()

Returns a hash code for this range.

16 boolean hasLowerBound()

Returns true if this range has a lower endpoint.

17 boolean hasUpperBound()

Returns true if this range has an upper endpoint.

18 Range<C> intersection(Range<C> connectedRange)

Returns the maximal range enclosed by both this range and connectedRange, if such a range exists.

19 boolean isConnected(Range<C> other)

Returns true if there exists a (possibly empty) range which is enclosed by both this range and other.

20 boolean isEmpty()

Returns true if this range is of the form [v..v) or (v..v].

21 static <C extends Comparable<?>> Range<C> lessThan(C endpoint)

Returns a range that contains all values strictly less than endpoint.

22 BoundType lowerBoundType()

Returns the type of this range's lower bound: BoundType.CLOSED if the range includes its lower endpoint, BoundType.OPEN if it does not.

23 C lowerEndpoint()

Returns the lower endpoint of this range.

24 static <C extends Comparable<?>> Range<C> open(C lower, C upper)

Returns a range that contains all values strictly greater than lower and strictly less than upper.

25 static <C extends Comparable<?>> Range<C> openClosed(C lower, C upper)

Returns a range that contains all values strictly greater than lower and less than or equal to upper.

26 static <C extends Comparable<?>> Range<C> range(C lower, BoundType lowerType, C upper, BoundType upperType)

Returns a range that contains any value from lower to upper, where each endpoint may be either inclusive (closed) or exclusive (open).

27 static <C extends Comparable<?>> Range<C> singleton(C value)

Returns a range that contains only the given value.

28 Range<C> span(Range<C> other)

Returns the minimal range that encloses both this range and other.

29 String toString()

Returns a string representation of this range, such as "[3..5)" (other examples are listed in the class documentation).

30 BoundType upperBoundType()

Returns the type of this range's upper bound: BoundType.CLOSED if the range includes its upper endpoint, BoundType.OPEN if it does not.

31 C upperEndpoint()

Returns the upper endpoint of this range.

32 static <C extends Comparable<?>> Range<C> upTo(C endpoint, BoundType boundType)

Returns a range with no lower bound up to the given endpoint, which may be either inclusive (closed) or exclusive (open).

Methods Inherited

This class inherits methods from the following class:

  • java.lang.Object

Example of Range class

Create the following java program using any editor of your choice in say C:/> Guava.

GuavaTester.java
import com.google.common.collect.ContiguousSet;
import com.google.common.collect.DiscreteDomain;
import com.google.common.collect.Range;
import com.google.common.primitives.Ints;

public class GuavaTester {

   public static void main(String args[]) {
      GuavaTester tester = new GuavaTester();
      tester.testRange();
   }

   private void testRange() {

      //create a range [a,b] = { x | a <= x <= b}
      Range<Integer> range1 = Range.closed(0, 9);	
      System.out.print("[0,9] : ");
      printRange(range1);		
      
      System.out.println("5 is present: " + range1.contains(5));
      System.out.println("(1,2,3) is present: " + range1.containsAll(Ints.asList(1, 2, 3)));
      System.out.println("Lower Bound: " + range1.lowerEndpoint());
      System.out.println("Upper Bound: " + range1.upperEndpoint());

      //create a range (a,b) = { x | a < x < b}
      Range<Integer> range2 = Range.open(0, 9);
      System.out.print("(0,9) : ");
      printRange(range2);

      //create a range (a,b] = { x | a < x <= b}
      Range<Integer> range3 = Range.openClosed(0, 9);
      System.out.print("(0,9] : ");
      printRange(range3);

      //create a range [a,b) = { x | a <= x < b}
      Range<Integer> range4 = Range.closedOpen(0, 9);
      System.out.print("[0,9) : ");
      printRange(range4);

      //create an open ended range (9, infinity
      Range<Integer> range5 = Range.greaterThan(9);
      System.out.println("(9,infinity) : ");
      System.out.println("Lower Bound: " + range5.lowerEndpoint());
      System.out.println("Upper Bound present: " + range5.hasUpperBound());

      Range<Integer> range6 = Range.closed(3, 5);	
      printRange(range6);

      //check a subrange [3,5] in [0,9]
      System.out.println("[0,9] encloses [3,5]:" + range1.encloses(range6));

      Range<Integer> range7 = Range.closed(9, 20);	
      printRange(range7);
      
      //check ranges to be connected		
      System.out.println("[0,9] is connected [9,20]:" + range1.isConnected(range7));

      Range<Integer> range8 = Range.closed(5, 15);	

      //intersection
      printRange(range1.intersection(range8));

      //span
      printRange(range1.span(range8));
   }

   private void printRange(Range<Integer> range) {		
   
      System.out.print("[ ");
      
      for(int grade : ContiguousSet.create(range, DiscreteDomain.integers())) {
         System.out.print(grade +" ");
      }
      System.out.println("]");
   }
}

Verify the Result

Compile the class using javac compiler as follows:

C:\Guava>javac GuavaTester.java

Now run the GuavaTester to see the result.

C:\Guava>java GuavaTester

See the result.

[0,9] : [ 0 1 2 3 4 5 6 7 8 9 ]
5 is present: true
(1,2,3) is present: true
Lower Bound: 0
Upper Bound: 9
(0,9) : [ 1 2 3 4 5 6 7 8 ]
(0,9] : [ 1 2 3 4 5 6 7 8 9 ]
[0,9) : [ 0 1 2 3 4 5 6 7 8 ]
(9,infinity) : 
Lower Bound: 9
Upper Bound present: false
[ 3 4 5 ]
[0,9] encloses [3,5]:true
[ 9 10 11 12 13 14 15 16 17 18 19 20 ]
[0,9] is connected [9,20]:true
[ 5 6 7 8 9 ]
[ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ]


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