Title: OCM Version Management
Right now, the OCM tools provides basic versioning features:

* Check in, check out.
* Retrieve version history (first version, last version, the complete
history, ...).
* Apply labels.

Later, we would like to add more advanced versioning support like version
compare, replace, revert, ... Each versioned object has to be mapped to a
mix:versionable JCR node. It is possible to specify this node type in the
xml class descriptor or with an annotation :

<a name="OCMVersionManagement-Checkin-Checkout"></a>
## Check in - Check out


    // Create a new page - first version
    Page page = new Page();
    page.setPath("/page");
    page.setTitle("Page Title");
    page.addParagraph(new Paragraph("para1"));
    page.addParagraph(new Paragraph("para2"));
    ocm.insert(page);
    ocm.save();
    
    // Update the page object and create a new version
    page.addParagraph(new Paragraph("para3"));
    ocm.checkout("/page");
    ocm.update(page);
    ocm.save();
    ocm.checkin("/page");
    
    // Update the page object and create a new version
    page.addParagraph(new Paragraph("para4"));
    ocm.checkout("/page");
    ocm.update(page);
    ocm.save();
    ocm.checkin("/page");


<a name="OCMVersionManagement-Retrievetheversionhistory"></a>
## Retrieve the version history


    VersionIterator versionIterator = ocm.getAllVersions("/page");
    while (versionIterator.hasNext())
    {
        Version version = (Version) versionIterator.next();
        System.out.println("version found : "+ version.getName() + " - " +
    			  version.getPath() + " - " + 
version.getCreated().getTime());
    }


<a name="OCMVersionManagement-Retrieveversiondescription"></a>
## Retrieve version description


    // Retrieve the first version description
    Version baseVersion = ocm.getBaseVersion("/page");
    System.out.println("Base version : " + baseVersion.getName());
    
    // Retrieve the latest version description
    Version rootVersion = ocm.getRootVersion("/page");
    System.out.println("Root version : " + rootVersion.getName());


<a name="OCMVersionManagement-Retrievetheobjectstatematchingtoaspecificversion"></a>
## Retrieve the object state matching to a specific version


    //Get the object matching to the first version
    Page  page = (Page) ocm.getObject( "/page", "1.0");


<a name="OCMVersionManagement-Usingversionlabels"></a>
## Using version labels


    Page page = new Page();
    page.setPath("/page");
    page.setTitle("Page Title");
    page.addParagraph(new Paragraph("para1"));
    page.addParagraph(new Paragraph("para2"));
    ocm.insert(page);
    ocm.save();
    
    // Checkin with some labels
    page.addParagraph(new Paragraph("para3"));
    ocm.checkout("/page");
    ocm.update(page);
    ocm.save();
    ocm.checkin("/page", new String[]
 {"A", "B"});
    
    // Checkin with some labels
    page.addParagraph(new Paragraph("para4"));
    ocm.checkout("/page");
    ocm.update(page);
    ocm.save();
    ocm.checkin("/page", new String[]
 {"C", "D"});
    
    // Retrieve all labels
    String[]
 allLabels = ocm.getAllVersionLabels("/page");
    assertTrue("Incorrect number of labels", allLabels.length == 4);
    
    // Retrieve labels assigned to the version 1.1
    String[]
 versionLabels = ocm.getVersionLabels("/page", "1.1");
    assertTrue("Incorrect number of labels", versionLabels.length == 2);
    assertTrue("Incorrect label", versionLabels[0]
.equals("C") || versionLabels[0].equals("D"));
    assertTrue("Incorrect label", versionLabels[1]
.equals("C") || versionLabels[0].equals("D"));