org.hsqldb.lib
Class HsqlArrayHeap

java.lang.Object
  org.hsqldb.lib.HsqlArrayHeap

All Implemented Interfaces:

HsqlHeap

Direct Known Subclasses:

HsqlTimer.TaskQueue

public class HsqlArrayHeap

extends Object

implements HsqlHeap

An HsqlHeap implementation backed by an array of objects and an ObjectComparator. This implementation is non-blocking, dynamically resizing and thread-safe.

Since:

1.7.2

Version:

1.7.2

Author:

boucherb@users.sourceforge.net

Field Summary

protected int	count
protected Object[]	heap
protected ObjectComparator	oc

Constructor Summary

HsqlArrayHeap(int capacity, ObjectComparator comparator)
Creates a new HsqlArrayHeap with the given initial capacity, using the specified ObjectComparator to maintain the heap invariant.

Method Summary

void	add(Object o) Adds the specified element to this Heap.
void	clear() Removes all of the elements from this Heap.
boolean	isEmpty() Retrieves whether this Heap is empty.
boolean	isFull() Retrieves whether this Heap is full.
Object	peek() Retrieves the least element from this Heap, without removing it.
Object	remove() Retrieves the least element from this Heap, removing it in the process.
int	size() Retrieves the number of elements currently in this Heap.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

oc

protected ObjectComparator oc

count

protected int count

heap

protected Object[] heap

Constructor Detail

HsqlArrayHeap

public HsqlArrayHeap(int capacity,
                     ObjectComparator comparator)
              throws IllegalArgumentException

Creates a new HsqlArrayHeap with the given initial capacity, using the specified ObjectComparator to maintain the heap invariant.

Throws:

IllegalArgumentException - if capacity less or equal to zero or comparator is null

Method Detail

clear

public void clear()

Description copied from interface: HsqlHeap

Removes all of the elements from this Heap.

Specified by:

clear in interface HsqlHeap

add

public void add(Object o)
         throws IllegalArgumentException,
                RuntimeException

Description copied from interface: HsqlHeap

Adds the specified element to this Heap.

Specified by:

add in interface HsqlHeap

Parameters:

o - The element to add

Throws:

IllegalArgumentException - if the implementation does not accept elements of the supplied type (optional) throws HsqlUnsupportedOperationException if the implementation dictates that this Heap is not currently accepting additions or that this Heap is currently full (optional)

RuntimeException

isEmpty

public boolean isEmpty()

Description copied from interface: HsqlHeap

Retrieves whether this Heap is empty.

Specified by:

isEmpty in interface HsqlHeap

isFull

public boolean isFull()

Description copied from interface: HsqlHeap

Retrieves whether this Heap is full.

Specified by:

isFull in interface HsqlHeap

peek

public Object peek()

Description copied from interface: HsqlHeap

Retrieves the least element from this Heap, without removing it.

Specified by:

peek in interface HsqlHeap

Returns:

the least element from this Heap

remove

public Object remove()

Description copied from interface: HsqlHeap

Retrieves the least element from this Heap, removing it in the process.

Specified by:

remove in interface HsqlHeap

Returns:

the least element from this Heap

size

public int size()

Description copied from interface: HsqlHeap

Retrieves the number of elements currently in this Heap.

Specified by:

size in interface HsqlHeap

Returns:

the number of elements currently in this Heap

toString

public String toString()