ej.style.selector

Class SpecificityHelper

java.lang.Object

ej.style.selector.SpecificityHelper

public class SpecificityHelper
extends java.lang.Object

Provides some facilities to compute selectors specificity.

The specificity is divided in four parts (defined by CSS2 specification).

• count 1 if the declaration is from is a 'style' attribute rather than a rule with a selector, 0 otherwise (= a)
• count the number of ID attributes in the selector (= b)
• count the number of other attributes and pseudo-classes in the selector (= c)
• count the number of element names and pseudo-elements in the selector (= d)

Concatenating the four numbers a-b-c-d (in a number system with a large base) gives the specificity.

In this implementation, each number is stored on a byte in a integer.

Field Summary

Fields

Modifier and Type	Field and Description
static int	A_SHIFT The a number shift in the integer.
static int	B_SHIFT The b number shift in the integer.
static int	C_SHIFT The c number shift in the integer.
static int	D_SHIFT The d number shift in the integer.

Method Summary

Modifier and Type	Method and Description
static int	getSpecificity(int a, int b, int c, int d) Computes the specificity for the given four numbers a, b, c and d.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

A_SHIFT

public static final int A_SHIFT

The a number shift in the integer.

See Also:

Constant Field Values

B_SHIFT

public static final int B_SHIFT

The b number shift in the integer.

See Also:

Constant Field Values

C_SHIFT

public static final int C_SHIFT

The c number shift in the integer.

See Also:

Constant Field Values

D_SHIFT

public static final int D_SHIFT

The d number shift in the integer.

See Also:

Constant Field Values

Method Detail

getSpecificity

public static int getSpecificity(int a,
                                 int b,
                                 int c,
                                 int d)

Computes the specificity for the given four numbers a, b, c and d.

Parameters:

a - the a number.

b - the b number.

c - the c number.

d - the d number.

Returns:

the specificity for the given numbers.