com.tavianator.sangria.core

Class Priority

java.lang.Object

com.tavianator.sangria.core.Priority

All Implemented Interfaces:

Comparable<Priority>

public class Priority
extends Object
implements Comparable<Priority>

A loosely-coupled, infinitely divisible priority/weight system.

This class implements an extensible priority system based on lexicographical ordering. In its simplest use, Priority.create(0) is ordered before Priority.create(1), then Priority.create(2), etc.

To create a priority that is ordered between two existing ones, simply add another parameter: Priority.create(1, 1) comes after Priority.create(1), but before Priority.create(2). In this way, priorities can always be inserted anywhere in a sequence.

The next() method creates a priority that is ordered immediately following the current one, and is distinct from all priorities obtained by any other means. This provides a convenient way to order entire segments of lists.

A special priority, obtained by Priority.getDefault(), sorts before all other priorities.

Since:

1.1

Version:

1.1

Author:

Tavian Barnes (tavianator@tavianator.com)

Method Summary

Methods

Modifier and Type	Method and Description
int	compareTo(Priority o)
static Priority	create(int weight, int... weights) Create a Priority with the given sequence.
boolean	equals(Object obj)
static Priority	getDefault()
int	hashCode()
boolean	isDefault()
Priority	next()
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

getDefault

public static Priority getDefault()

Returns:

The default priority, which comes before all other priorities.

create

public static Priority create(int weight,
              int... weights)

Create a Priority with the given sequence.

Parameters:

weight - The first value of the weight sequence.

weights - An integer sequence. These sequences are sorted lexicographically, so Priority.create(1) sorts before Priority.create(1, 1), which sorts before Priority.create(2).

Returns:

A new Priority.

isDefault

public boolean isDefault()

Returns:

Whether this priority originated in a call to getDefault().

next

public Priority next()

Returns:

A new Priority which immediately follows this one, and which is distinct from all other priorities obtained by create(int, int...).

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

compareTo

public int compareTo(Priority o)

Specified by:

compareTo in interface Comparable<Priority>

toString

public String toString()

Overrides:

toString in class Object