com.itextpdf.kernel.utils.objectpathitems

Class ObjectPath

java.lang.Object

com.itextpdf.kernel.utils.objectpathitems.ObjectPath

Direct Known Subclasses:

TrailerPath

public class ObjectPath
extends Object

Class that helps to find two corresponding objects in the compared documents and also keeps track of the already met during comparing process parent indirect objects.

You could say that CompareObjectPath instance consists of two parts: direct path and indirect path. Direct path defines path to the currently comparing objects in relation to base objects. It could be empty, which would mean that currently comparing objects are base objects themselves. Base objects are the two indirect objects from the comparing documents which are in the same position in the pdf trees. Another part, indirect path, defines which indirect objects were met during comparison process to get to the current base objects. Indirect path is needed to avoid infinite loops during comparison.

Field Summary

Fields

Modifier and Type	Field and Description
protected Stack<LocalPathItem>	path

Constructor Summary

Constructors

Constructor and Description
ObjectPath() Creates empty ObjectPath.
ObjectPath(ObjectPath objectPath) Creates an ObjectPath object from another ObjectPath object, passed as argument.
ObjectPath(PdfIndirectReference baseCmpObject, PdfIndirectReference baseOutObject) Creates CompareObjectPath with corresponding base objects in two documents.
ObjectPath(PdfIndirectReference baseCmpObject, PdfIndirectReference baseOutObject, Stack<LocalPathItem> path, Stack<IndirectPathItem> indirects)

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj) Method returns true if this ObjectPath instance equals to the passed object.
PdfIndirectReference	getBaseCmpObject() Method returns current base PdfIndirectReference object in the cmp document.
PdfIndirectReference	getBaseOutObject() Method returns current base PdfIndirectReference object in the out document.
Stack<IndirectPathItem>	getIndirectPath() Gets indirect path which denotes sequence of the indirect references that were passed in comparing process to get to the current base objects.
Stack<LocalPathItem>	getLocalPath() Gets local (or direct) path that denotes sequence of the path items from base object to the comparing direct object.
int	hashCode() Method returns a hash code of this ObjectPath instance.
boolean	isComparing(PdfIndirectReference cmpObject, PdfIndirectReference outObject) This method is used to define if given objects were already met in the path to the current base objects.
void	pop() Removes the last path item from the direct path.
void	pushArrayItemToPath(int index) Adds array item to the direct path.
void	pushDictItemToPath(PdfName key) Adds dictionary item to the direct path.
void	pushOffsetToPath(int offset) Adds offset item to the direct path.
ObjectPath	resetDirectPath(PdfIndirectReference baseCmpObject, PdfIndirectReference baseOutObject) Creates a new ObjectPath instance with two new given base objects, which are supposed to be nested in the base objects of the current instance of the ObjectPath.
String	toString() Method returns a string representation of the direct path stored in this ObjectPath instance.
Node	toXmlNode(Document document) Creates an xml node that describes a direct path stored in this ObjectPath instance.

Methods inherited from class java.lang.Object

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

Field Detail

path

protected Stack<LocalPathItem> path

Constructor Detail

ObjectPath

public ObjectPath()

Creates empty ObjectPath.

ObjectPath

public ObjectPath(ObjectPath objectPath)

Creates an ObjectPath object from another ObjectPath object, passed as argument.

Parameters:

objectPath - an ObjectPath object to create from.

ObjectPath

public ObjectPath(PdfIndirectReference baseCmpObject,
                  PdfIndirectReference baseOutObject)

Creates CompareObjectPath with corresponding base objects in two documents.

Parameters:

baseCmpObject - base object in cmp document.

baseOutObject - base object in out document.

ObjectPath

public ObjectPath(PdfIndirectReference baseCmpObject,
                  PdfIndirectReference baseOutObject,
                  Stack<LocalPathItem> path,
                  Stack<IndirectPathItem> indirects)

Method Detail

resetDirectPath

public ObjectPath resetDirectPath(PdfIndirectReference baseCmpObject,
                                  PdfIndirectReference baseOutObject)

Creates a new ObjectPath instance with two new given base objects, which are supposed to be nested in the base objects of the current instance of the ObjectPath. This method is used to avoid infinite loop in case of circular references in pdf documents objects structure.

Basically, this method creates copy of the current CompareObjectPath instance, but resets information of the direct paths, and also adds current CompareObjectPath instance base objects to the indirect references chain that denotes a path to the new base objects.

Parameters:

baseCmpObject - new base object in cmp document.

baseOutObject - new base object in out document.

Returns:

new ObjectPath instance, which stores chain of the indirect references which were already met to get to the new base objects.

isComparing

public boolean isComparing(PdfIndirectReference cmpObject,
                           PdfIndirectReference outObject)

This method is used to define if given objects were already met in the path to the current base objects. If this method returns true it basically means that we found a loop in the objects structure and that we already compared these objects.

Parameters:

cmpObject - cmp object to check if it was already met in base objects path.

outObject - out object to check if it was already met in base objects path.

Returns:

true if given objects are contained in the path and therefore were already compared.

pushArrayItemToPath

public void pushArrayItemToPath(int index)

Adds array item to the direct path. See ArrayPathItem.

Parameters:

index - index in the array of the direct object to be compared.

pushDictItemToPath

public void pushDictItemToPath(PdfName key)

Adds dictionary item to the direct path. See DictPathItem.

Parameters:

key - key in the dictionary to which corresponds direct object to be compared.

pushOffsetToPath

public void pushOffsetToPath(int offset)

Adds offset item to the direct path. See OffsetPathItem.

Parameters:

offset - offset to the specific byte in the stream that is compared.

pop

public void pop()

Removes the last path item from the direct path.

getLocalPath

public Stack<LocalPathItem> getLocalPath()

Gets local (or direct) path that denotes sequence of the path items from base object to the comparing direct object.

Returns:

direct path to the comparing object.

getIndirectPath

public Stack<IndirectPathItem> getIndirectPath()

Gets indirect path which denotes sequence of the indirect references that were passed in comparing process to get to the current base objects.

Returns:

indirect path to the current base objects.

getBaseCmpObject

public PdfIndirectReference getBaseCmpObject()

Method returns current base PdfIndirectReference object in the cmp document.

Returns:

current base PdfIndirectReference object in the cmp document.

getBaseOutObject

public PdfIndirectReference getBaseOutObject()

Method returns current base PdfIndirectReference object in the out document.

Returns:

current base object in the out document.

toXmlNode

public Node toXmlNode(Document document)

Creates an xml node that describes a direct path stored in this ObjectPath instance.

Parameters:

document - xml document, to which this xml node will be added.

Returns:

an xml node describing direct path.

toString

public String toString()

Method returns a string representation of the direct path stored in this ObjectPath instance.

Overrides:

toString in class Object

Returns:

a string representation of the direct path.

hashCode

public int hashCode()

Method returns a hash code of this ObjectPath instance.

Overrides:

hashCode in class Object

Returns:

a int hash code of this ObjectPath instance.

equals

public boolean equals(Object obj)

Method returns true if this ObjectPath instance equals to the passed object.

Overrides:

equals in class Object

Returns:

true - if this ObjectPath instance equals to the passed object.