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Guava – Range Class

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Range class

Range class 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.NoMethod & Description
1static <C extends Comparable<?>> Range<C> all()Returns a range that contains every value of type C.
2boolean apply(C input)Deprecated.Provided only to satisfy the Predicate interface; use contains(C) instead.
3static <C extends Comparable<?>> Range<C> atLeast(C endpoint)Returns a range that contains all values greater than or equal to endpoint.
4static <C extends Comparable<?>> Range<C> atMost(C endpoint)Returns a range that contains all values less than or equal to endpoint.
5Range<C> canonical(DiscreteDomain<C> domain)Returns the canonical form of this range in the given domain.
6static <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.
7static <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.
8boolean contains(C value)Returns true if value is within the bounds of this range.
9boolean containsAll(Iterable<? extends C> values)Returns true if every element in values is contained in this range.
10static <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.
11static <C extends Comparable<?>> Range<C> encloseAll(Iterable<C> values)Returns the minimal range that contains all of the given values.
12boolean encloses(Range<C> other)Returns true if the bounds of other do not extend outside the bounds of this range.
13boolean equals(Object object)Returns true if object is a range having the same endpoints and bound types as this range.
14static <C extends Comparable<?>> Range<C> greaterThan(C endpoint)Returns a range that contains all values strictly greater than endpoint.
15int hashCode()Returns a hash code for this range.
16boolean hasLowerBound()Returns true if this range has a lower endpoint.
17boolean hasUpperBound()Returns true if this range has an upper endpoint.
18Range<C> intersection(Range<C> connectedRange)Returns the maximal range enclosed by both this range and connectedRange, if such a range exists.
19boolean isConnected(Range<C> other)Returns true if there exists a (possibly empty) range which is enclosed by both this range and other.
20boolean isEmpty()Returns true if this range is of the form [v..v) or (v..v].
21static <C extends Comparable<?>> Range<C> lessThan(C endpoint)Returns a range that contains all values strictly less than endpoint.
22BoundType 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.
23C lowerEndpoint()Returns the lower endpoint of this range.
24static <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.
25static <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.
26static <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).
27static <C extends Comparable<?>> Range<C> singleton(C value)Returns a range that contains only the given value.
28Range<C> span(Range<C> other)Returns the minimal range that encloses both this range and other.
29String toString()Returns a string representation of this range, such as “[3..5)” (other examples are listed in the class documentation).
30BoundType 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.
31C upperEndpoint()Returns the upper endpoint of this range.
32static <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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