com.xmlmind.xmleditapp.cmd.diff

Class Diff

java.lang.Object

com.xmlmind.xmleditapp.cmd.diff.Diff

public final class Diff
extends Object

Compare two revisions of the same initial document.

Comparison of revisions must have been enabled in the initial document using DiffSupport.addSerialNumbers(com.xmlmind.xml.doc.Document) (or DiffSupport.addRevisions(com.xmlmind.xml.doc.Document)).

Constructor Summary

Constructors

Constructor and Description
Diff() Constructs an object allowing to two revisions of the same initial document.

Method Summary

Modifier and Type	Method and Description
static String	canDiff(Document origDoc, Document revDoc) Returns a null string if specified documents can be compared for changes.
void	diff(Document origDoc, Document revDoc, List<Change> changes) Compares specified document for changes.
static boolean	hasPreserveSpace(DocumentType docType, Element element) Helper: returns true if specied element has or inherits xml:space="preserve"; returns false otherwise.
static void	printChanges(PrintStream out, List<Change> changes, boolean detailed) Writes on specified output stream specified list of changes.

Methods inherited from class java.lang.Object

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

Constructor Detail

Diff

public Diff()

Constructs an object allowing to two revisions of the same initial document.

This object is not designed to be reused several times.

Method Detail

canDiff

public static String canDiff(Document origDoc,
                             Document revDoc)

Returns a null string if specified documents can be compared for changes. Returns a non-null string --an error message--if specified documents cannot be compared for changes.

diff

public void diff(Document origDoc,
                 Document revDoc,
                 List<Change> changes)
          throws DiffException

Compares specified document for changes.

Parameters:

origDoc - the original document

revDoc - a revised copy of the original document

changes - detected changes, if any, are appended to this list (after first clearing it)

Throws:

DiffException - if, for any reason, an error occurs during the execution of this method.

Note that this method first starts by invoking canDiff(com.xmlmind.xml.doc.Document, com.xmlmind.xml.doc.Document) and will throw an exception if canDiff(com.xmlmind.xml.doc.Document, com.xmlmind.xml.doc.Document) returns an error message.

hasPreserveSpace

public static boolean hasPreserveSpace(DocumentType docType,
                                       Element element)

Helper: returns true if specied element has or inherits xml:space="preserve"; returns false otherwise.

Parameters:

docType - the type of the document containing element; may be null

element - the element to be tested

Returns:

true specified element is space preserving; false otherwise

printChanges

public static void printChanges(PrintStream out,
                                List<Change> changes,
                                boolean detailed)

Writes on specified output stream specified list of changes.

This function may be used when testing or debugging. It also may be used to implement a command-line diff utility.