com.vaadin.shared.ui.grid
Class Range

java.lang.Object
  com.vaadin.shared.ui.grid.Range

All Implemented Interfaces:

java.io.Serializable

public final class Range
extends java.lang.Object
implements java.io.Serializable

An immutable representation of a range, marked by start and end points.

The range is treated as inclusive at the start, and exclusive at the end. I.e. the range [0..1[ has the length 1, and represents one integer: 0.

The range is considered empty if the start is the same as the end.

Since:

7.4

Author:

Vaadin Ltd

See Also:

Serialized Form

Method Summary

static Range	between(int start, int end) Creates a range between two integers.
Range	combineWith(Range other) Combines two ranges to create a range containing all values in both ranges, provided there are no gaps between the ranges.
boolean	contains(int integer) Checks whether an integer is found within this range.
boolean	endsAfter(Range other) Checks whether this range ends after the end of another range.
boolean	endsBefore(Range other) Checks whether this range ends before the start of another range.
boolean	equals(java.lang.Object obj)
Range	expand(int startDelta, int endDelta) Creates a range that is expanded the given amounts in both ends.
int	getEnd() Returns the exclusive end point of this range.
int	getStart() Returns the inclusive start point of this range.
int	hashCode()
boolean	intersects(Range other) Checks whether this range and another range are at least partially covering the same values.
boolean	isEmpty() Checks whether the range has no elements between the start and end.
boolean	isSubsetOf(Range other) Checks whether this range is a subset of another range.
int	length() The number of integers contained in the range.
Range	offsetBy(int offset) Get a range that is based on this one, but offset by a number.
Range[]	partitionWith(Range other) Overlay this range with another one, and partition the ranges according to how they position relative to each other.
Range	restrictTo(Range bounds) Limits this range to be within the bounds of the provided range.
Range[]	splitAt(int integer) Split the range into two at a certain integer.
Range[]	splitAtFromStart(int length) Split the range into two after a certain number of integers into the range.
boolean	startsAfter(Range other) Checks whether this range starts after the end of another range.
boolean	startsBefore(Range other) Checks whether this range starts before the start of another range.
java.lang.String	toString()
static Range	withLength(int start, int length) Creates a range from a start point, with a given length.
static Range	withOnly(int integer) Creates a range object representing a single integer.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

withOnly

public static Range withOnly(int integer)

Creates a range object representing a single integer.

Parameters:

integer - the number to represent as a range

Returns:

the range represented by integer

between

public static Range between(int start,
                            int end)
                     throws java.lang.IllegalArgumentException

Creates a range between two integers.

The range start is inclusive and the end is exclusive. So, a range "between" 0 and 5 represents the numbers 0, 1, 2, 3 and 4, but not 5.

Parameters:

start - the start of the the range, inclusive

end - the end of the range, exclusive

Returns:

a range representing [start..end[

Throws:

java.lang.IllegalArgumentException - if start > end

withLength

public static Range withLength(int start,
                               int length)
                        throws java.lang.IllegalArgumentException

Creates a range from a start point, with a given length.

Parameters:

start - the first integer to include in the range

length - the length of the resulting range

Returns:

a range starting from start, with length number of integers following

Throws:

java.lang.IllegalArgumentException - if length < 0

getStart

public int getStart()

Returns the inclusive start point of this range.

Returns:

the start point of this range

getEnd

public int getEnd()

Returns the exclusive end point of this range.

Returns:

the end point of this range

length

public int length()

The number of integers contained in the range.

Returns:

the number of integers contained in the range

isEmpty

public boolean isEmpty()

Checks whether the range has no elements between the start and end.

Returns:

true iff the range contains no elements.

intersects

public boolean intersects(Range other)

Checks whether this range and another range are at least partially covering the same values.

Parameters:

other - the other range to check against

Returns:

true if this and other intersect

contains

public boolean contains(int integer)

Checks whether an integer is found within this range.

Parameters:

integer - an integer to test for presence in this range

Returns:

true iff integer is in this range

isSubsetOf

public boolean isSubsetOf(Range other)

Checks whether this range is a subset of another range.

Returns:

true iff other completely wraps this range

partitionWith

public Range[] partitionWith(Range other)

Overlay this range with another one, and partition the ranges according to how they position relative to each other.

The three partitions are returned as a three-element Range array:

• Elements in this range that occur before elements in other.
• Elements that are shared between the two ranges.
• Elements in this range that occur after elements in other.

Parameters:

other - the other range to act as delimiters.

Returns:

a three-element Range array of partitions depicting the elements before (index 0), shared/inside (index 1) and after (index 2).

offsetBy

public Range offsetBy(int offset)

Get a range that is based on this one, but offset by a number.

Parameters:

offset - the number to offset by

Returns:

a copy of this range, offset by offset

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

startsBefore

public boolean startsBefore(Range other)

Checks whether this range starts before the start of another range.

Parameters:

other - the other range to compare against

Returns:

true iff this range starts before the other

endsBefore

public boolean endsBefore(Range other)

Checks whether this range ends before the start of another range.

Parameters:

other - the other range to compare against

Returns:

true iff this range ends before the other

endsAfter

public boolean endsAfter(Range other)

Checks whether this range ends after the end of another range.

Parameters:

other - the other range to compare against

Returns:

true iff this range ends after the other

startsAfter

public boolean startsAfter(Range other)

Checks whether this range starts after the end of another range.

Parameters:

other - the other range to compare against

Returns:

true iff this range starts after the other

splitAt

public Range[] splitAt(int integer)

Split the range into two at a certain integer.

Example: [5..10[.splitAt(7) == [5..7[, [7..10[

Parameters:

integer - the integer at which to split the range into two

Returns:

an array of two ranges, with [start..integer[ in the first element, and [integer..end[ in the second element.

If integer is less than start, [empty, this ] is returned. if integer is equal to or greater than end, [this, empty] is returned instead.

splitAtFromStart

public Range[] splitAtFromStart(int length)

Split the range into two after a certain number of integers into the range.

Calling this method is equivalent to calling splitAt(getStart()+length);

Example: [5..10[.splitAtFromStart(2) == [5..7[, [7..10[

Parameters:

length - the length at which to split this range into two

Returns:

an array of two ranges, having the length-first elements of this range, and the second range having the rest. If length ≤ 0, the first element will be empty, and the second element will be this range. If length ≥ length(), the first element will be this range, and the second element will be empty.

combineWith

public Range combineWith(Range other)
                  throws java.lang.IllegalArgumentException

Combines two ranges to create a range containing all values in both ranges, provided there are no gaps between the ranges.

Parameters:

other - the range to combine with this range

Returns:

the combined range

Throws:

java.lang.IllegalArgumentException - if the two ranges aren't connected

expand

public Range expand(int startDelta,
                    int endDelta)
             throws java.lang.IllegalArgumentException

Creates a range that is expanded the given amounts in both ends.

Parameters:

startDelta - the amount to expand by in the beginning of the range

endDelta - the amount to expand by in the end of the range

Returns:

an expanded range

Throws:

java.lang.IllegalArgumentException - if the new range would have start > end

restrictTo

public Range restrictTo(Range bounds)

Limits this range to be within the bounds of the provided range.

This is basically an optimized way of calculating partitionWith(Range)[1] without the overhead of defining the parts that do not overlap.

If the two ranges do not intersect, an empty range is returned. There are no guarantees about the position of that range.

Parameters:

bounds - the bounds that the returned range should be limited to

Returns:

a bounded range