Module utilities

Package de.grogra.util

Class HierarchicalQueue

java.lang.Object

java.io.OutputStream

de.grogra.util.OutputQueue

de.grogra.util.HierarchicalQueue

All Implemented Interfaces:

Closeable, DataOutput, Flushable, ObjectOutput, AutoCloseable

Direct Known Subclasses:

GraphQueue, XAQueue

public class HierarchicalQueue
extends OutputQueue
implements ObjectOutput

A HierarchicalQueue equips an OutputQueue with a record-like, hierarchical structure. Each record is called an item, the type of which is identified by the first int-value of the record. Items follow each other in a linked list (the link is established by relative addresses which are stored in an item's header structure, see below). The item of type BEGIN_LEVEL indicates a nesting of items, it contains another linked list of items.

A whole item is represented by the following structure in the int-queue:

1. int-value at offset 0: item type
2. int-value at offset 1: difference between this item's address (the absolute index of offset 0) and the address of the previous item. If no previous item exists, -1 is used for the latter address. The first item which is contained in a new level has no previous item.
3. The following ints contain the total number of int, byte, long, float, double, Object-values in this order. If the total number of values of one of these types is always the same for the item type, this number is not present in the structure. The total number of values for an item type is set by the method setItemSize(int, int, int, int, int, int, int).
4. The following ints represent the data of the item in its specific format

An item of type BEGIN_LEVEL is used to store the whole information of the nested items it contains. It uses an additional int-value as first value of its data: Its value is the difference between the address of the last contained item and this item.

Author:

Ole Kniemeyer

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
final class	HierarchicalQueue.Cursor
static class	HierarchicalQueue.Data
class	HierarchicalQueue.Reader

Field Summary

Fields

Modifier and Type	Field	Description
static final int	BEGIN_LEVEL
static final int	IS_FINISHED
static final int	ITEM_AND_BITS_MASK
static final int	ITEM_MASK
static final int	MAX_UNUSED_BIT
static final int	MIN_UNUSED_BIT
static final int	MIN_UNUSED_ITEM
static final int	NEXT_EXISTS
protected final ObjectOutputStream	out

Constructor Summary

Constructors

Constructor	Description
HierarchicalQueue(boolean usesObjectQueue, boolean createBackLinks)

Method Summary

Modifier and Type	Method	Description
final void	beginLevel()
final int	beginSkipBlock()
void	clear()
final HierarchicalQueue.Data	cloneData()
protected HierarchicalQueue.Data	createData()
final void	discardLevel()
final void	endLevel()
final void	endSkipBlock(int beginIndex)
final HierarchicalQueue.Cursor	getCursor(HierarchicalQueue.Cursor c)
final HierarchicalQueue.Data	getData()
final boolean	hasItems()
final boolean	hasItemsInCurrentLevel()
final void	moveTo(HierarchicalQueue.Cursor c)
void	restore(HierarchicalQueue.Data data)
final void	setItemSize(int item, int bsize, int isize, int lsize, int fsize, int dsize, int asize)
final void	writeItem(int item)
void	writeObject(Object o)
void	writeObjectInStream(Object o)

Methods inherited from class de.grogra.util.OutputQueue

close, dump, flush, write, write, write, writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeDouble, writeFloat, writeInt, writeLong, writeObjectInQueue, writeShort, writeUTF

Methods inherited from class java.io.OutputStream

nullOutputStream

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.DataOutput

writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeDouble, writeFloat, writeInt, writeLong, writeShort, writeUTF

Methods inherited from interface java.io.ObjectOutput

close, flush, write, write, write

Field Details

NEXT_EXISTS

public static final int NEXT_EXISTS

See Also:

• Constant Field Values

IS_FINISHED

public static final int IS_FINISHED

See Also:

• Constant Field Values

ITEM_MASK

public static final int ITEM_MASK

See Also:

• Constant Field Values

MIN_UNUSED_BIT

public static final int MIN_UNUSED_BIT

See Also:

• Constant Field Values

MAX_UNUSED_BIT

public static final int MAX_UNUSED_BIT

See Also:

• Constant Field Values

ITEM_AND_BITS_MASK

public static final int ITEM_AND_BITS_MASK

See Also:

• Constant Field Values

BEGIN_LEVEL

public static final int BEGIN_LEVEL

See Also:

• Constant Field Values

MIN_UNUSED_ITEM

public static final int MIN_UNUSED_ITEM

See Also:

• Constant Field Values

out

protected final ObjectOutputStream out

Constructor Details

HierarchicalQueue

public HierarchicalQueue(boolean usesObjectQueue,
 boolean createBackLinks)

Method Details

clear

public void clear()

Overrides:

clear in class OutputQueue

setItemSize

public final void setItemSize(int item,
 int bsize,
 int isize,
 int lsize,
 int fsize,
 int dsize,
 int asize)

beginLevel

public final void beginLevel()

endLevel

public final void endLevel()

discardLevel

public final void discardLevel()

writeItem

public final void writeItem(int item)

hasItems

public final boolean hasItems()

hasItemsInCurrentLevel

public final boolean hasItemsInCurrentLevel()

writeObject

public void writeObject(Object o)
                 throws IOException

Specified by:

writeObject in interface ObjectOutput

Overrides:

writeObject in class OutputQueue

Throws:

IOException

writeObjectInStream

public void writeObjectInStream(Object o)
                         throws IOException

Throws:

IOException

beginSkipBlock

public final int beginSkipBlock()

endSkipBlock

public final void endSkipBlock(int beginIndex)

getCursor

public final HierarchicalQueue.Cursor getCursor(HierarchicalQueue.Cursor c)

moveTo

public final void moveTo(HierarchicalQueue.Cursor c)

createData

protected HierarchicalQueue.Data createData()

getData

public final HierarchicalQueue.Data getData()

cloneData

public final HierarchicalQueue.Data cloneData()

restore

public void restore(HierarchicalQueue.Data data)