Package org.apache.wicket.markup.head

Class PriorityFirstComparator

java.lang.Object

org.apache.wicket.markup.head.PriorityFirstComparator

All Implemented Interfaces:

Serializable, Comparator<ResourceAggregator.RecordedHeaderItem>

public class PriorityFirstComparator
extends Object
implements Comparator<ResourceAggregator.RecordedHeaderItem>, Serializable

Implements the default sorting algorithm for HeaderItems. PriorityHeaderItems are moved to the front, inverting the component order to convert the child-first into a parent-first order. If renderPageFirst is true, the head from the markup of a page is moved to the front of the header, directly after the priority header items.

Author:

papegaaij

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	PriorityFirstComparator.HeaderItemType

Constructor Summary

Constructors

Constructor	Description
PriorityFirstComparator(boolean renderPageFirst)	Construct.

Method Summary

Modifier and Type	Method	Description
int	compare(ResourceAggregator.RecordedHeaderItem o1, ResourceAggregator.RecordedHeaderItem o2)
protected int	compareWithinGroup(ResourceAggregator.RecordedHeaderItem item1, ResourceAggregator.RecordedHeaderItem item2)	Compares two header items that belong in the same group.
protected PriorityFirstComparator.HeaderItemType	getItemType(ResourceAggregator.RecordedHeaderItem item)	Determines the type of the item: priority, page or component.
protected int	inversedComponentOrder(ResourceAggregator.RecordedHeaderItem item1, ResourceAggregator.RecordedHeaderItem item2)	Compare two recorded PriorityHeaderItems, converting the child-first order into parent-first.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Detail

PriorityFirstComparator

public PriorityFirstComparator(boolean renderPageFirst)

Construct.

Parameters:

renderPageFirst - when true, the header of the page is moved to the front.

Method Detail

compare

public int compare(ResourceAggregator.RecordedHeaderItem o1,
                   ResourceAggregator.RecordedHeaderItem o2)

Specified by:

compare in interface Comparator<ResourceAggregator.RecordedHeaderItem>

compareWithinGroup

protected int compareWithinGroup(ResourceAggregator.RecordedHeaderItem item1,
                                 ResourceAggregator.RecordedHeaderItem item2)

Compares two header items that belong in the same group.

Parameters:

item1 -

item2 -

Returns:

0 by default to preserve the order

inversedComponentOrder

protected int inversedComponentOrder(ResourceAggregator.RecordedHeaderItem item1,
                                     ResourceAggregator.RecordedHeaderItem item2)

Compare two recorded PriorityHeaderItems, converting the child-first order into parent-first.

Parameters:

item1 - first item

item2 - second item

Returns:

-1, 0 or 1 if item1 needs to be rendered before, unchanged or after item2.

See Also:

ResourceAggregator.RecordedHeaderItemLocation.getDepth()

getItemType

protected PriorityFirstComparator.HeaderItemType getItemType(ResourceAggregator.RecordedHeaderItem item)

Determines the type of the item: priority, page or component.

Parameters:

item -

Returns:

the type of the item