Class Range

java.lang.Object

Range

All Implemented Interfaces:

Comparable<Range>

public class Range
extends Object
implements Comparable<Range>

A class that represents a range of values on the integer number line. A range has two properties: a minimum value and a maximum value. Range objects always ensure that the following class invariant is true:

minimum <= maximum

Constructor Summary

Constructors

Constructor and Description
Range() Initialize this range with minimum value -1 and a maximum value 1.
Range(int min, int max) Initialize this range with the specified minimum and maximum values.

Method Summary

Modifier and Type	Method and Description
int	compareTo(Range other) Compares this range to another range.
boolean	contains(int value) Checks if value is inside this range.
int	getMaximum() Returns the maximum value of the range
int	getMinimum() Returns the minimum value of the range
Range	intersect(Range other) Returns a new range formed by the intersection of this range and the specified range.
boolean	overlaps(Range other) Checks if this range overlaps with another range.
String	toString() Returns the string representation of a range.
long	width() Returns the width of this range (the maximum value minus the minimum value).

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Range

public Range()

Initialize this range with minimum value -1 and a maximum value 1.

Range

public Range(int min,
             int max)

Initialize this range with the specified minimum and maximum values.

Parameters:

min - the minimum value of the range

max - the maximum value of the range

Throws:

IllegalArgumentException - if min is greater than max

Precondition:

min <= max

Method Detail

getMinimum

public int getMinimum()

Returns the minimum value of the range

Returns:

the minimum value of the range

getMaximum

public int getMaximum()

Returns the maximum value of the range

Returns:

the maximum value of the range

width

public long width()

Returns the width of this range (the maximum value minus the minimum value).

Returns:

the width of this range

contains

public boolean contains(int value)

Checks if value is inside this range. A value is considered inside this range if the value is greater than or equal to the minimum value of this range and value is less than or equal to the maximum value of this range.

Parameters:

value - the value to check

Returns:

true if value is inside this range, false otherwise

overlaps

public boolean overlaps(Range other)

Checks if this range overlaps with another range. Two ranges overlap if at least one int value is contained by both ranges. For example, the two ranges

[0, 5] and [4, 10] overlap because all values between 4 and 5 are contained by both ranges.

The two ranges

[0, 5] and [5, 8] overlap because both ranges contain the value 5

Parameters:

other - the other range to check

Returns:

true if this range overlaps with other, and false otherwise.

intersect

public Range intersect(Range other)

Returns a new range formed by the intersection of this range and the specified range. The intersection of two ranges is the range equal to the overlapping parts of the two ranges. For example, the intersection of the two ranges:

[0, 5] and [4, 10] is the range [4, 5].

The range [0, 0] is returned if the two ranges do not overlap.

Parameters:

other - the range to intersect with this range

Returns:

the new range equal to the intersection of this range and the other range

compareTo

public int compareTo(Range other)

Compares this range to another range.

Returns -1 if this range lies completely to the left of the other range. For example, the range [0, 1] lies completely to the left of the range [2, 10].

Returns 1 if this range lies completely to the right of the other range. For example, the range [10, 11] lies completely to the left of the range [2, 9].

Returns 0 if both ranges contain at least one common value. For example, the range [10, 11] shares one common value with the range [11, 15] (the number 11).

Specified by:

compareTo in interface Comparable<Range>

Parameters:

other - the range to compare

Returns:

-1 if this range lies completely to the left of the other range, 1 if this range lies completely to the right of the other range, and 0 otherwise

toString

public String toString()

Returns the string representation of a range. The string contains the minimum and maximum values separated by a comma and space all inside of a pair of square brackets. For example, the string

[2, 25]

represents the range whose minimum value is 2 and whose maximum value is 25

Overrides:

toString in class Object

Returns:

a string representation of the range