Openoffice.org UNO API

OpenOffice.org offers a language independent Application Programming Interface (API) which allows to program the office in different programming languages (e.g. C++, Java, Python, CLI, StarBasic, JavaScript, OLE). It allows us to use OpenOffice.org as service provider in other applications, extend it with new functionality or simply customize and control OpenOffice.org.

The API is based on the UNO component technology and that makes it really flexible and makes it possible to use one and the same API from different programming languages, all languages which are supported by UNO. Uno stands for Universal Network Objects. Uno is the interface based component model of OpenOffice.org. Uno components may be implemented in and accessed from any programming language for which a Uno implementation (AKA language binding) and an appropriate bridge or adapter exists.

Getting started with OpenOffice API and Java

Before you begin you need to install openoffice.org. You also need the following jar files on the class path:

1. juh.jar
2. jurt.jar
3. ridl.jar
4. unoil.jar

You can find these jar files in the installation directory in the subfolder program/classes. On linux for example a folder similar to /opt/openoffice.org 2.4/program/classes (on OOo 1.x.x and OOo 2.x.x).

The folder structure of OOo 3.0.0 changed a lot. The jars juh.jar, jurt.jar and ridl.jar are available at openoffice.org/ure/share/java
and unoil.jar is available at openoffice.org/basis3.0/program/classes.

You also need the program directory on your class path ( eg: /opt/openoffice.org3/program ), otherwise you’ll get the following error message: com.sun.star.comp.helper.BootstrapException: no office executable found!

First thing to do is to connect to the OpenOffice. They following code will start an instance of OpenOffice.

// Get the remote office component context
XComponentContext xContext = Bootstrap.bootstrap();

// Get the remote office service manager
XMultiComponentFactory xMCF = xContext.getServiceManager();

// Get the root frame (i.e. desktop) of openoffice framework.
Object oDesktop = xMCF.createInstanceWithContext("com.sun.star.frame.Desktop", xContext);

// Desktop has 3 interfaces. The XComponentLoader interface provides ability to load components.
XComponentLoader xCLoader = ( XComponentLoader ) UnoRuntime.queryInterface(XComponentLoader.class, oDesktop);

Now, we have to create an empty document in the new writer window.

// Create a document
XComponent document = xCLoader.loadComponentFromURL("private:factory/swriter", "_blank", 0, new PropertyValue[0]);

// Get the textdocument
XTextDocument aTextDocument = ( XTextDocument )UnoRuntime.queryInterface(com.sun.star.text.XTextDocument.class, document);

// Get its text
XText xText = aTextDocument.getText();

Now i can append my first piece text to the document

// Adding text to document
xText.insertString(xText.getEnd(), "My First OpenOffice Document", false);

Changing Font Styles and size

To set font family, style and size, we should set the property values CharFontName, CharFontStyleName and CharHeight of the XTextRange

XTextRange xTextRange = xText.createTextCursor();
((XTextCursor)xTextRange).gotoEnd(true);

XPropertySet xTextProps = (XPropertySet) UnoRuntime.queryInterface(
XPropertySet.class, xTextRange);
xTextProps.setPropertyValue("CharFontName", "Times New Roman");
xTextProps.setPropertyValue("CharFontStyleName", "Regular");
xTextProps.setPropertyValue("CharHeight", new Float(size));

Creating Table in OpenOffice

To create a table we need to create an instance of XMultiServiceFactory. And also the table ahould be initialize with total rows and columns before it can be inserted into the document

XMultiServiceFactory xMSF = ( XMultiServiceFactory ) UnoRuntime.queryInterface(XMultiServiceFactory.class, document);

// Creating a table with 3 rows and 4 columns
XTextTable xTextTable = ( XTextTable ) UnoRuntime.queryInterface(XTextTable.class, xMSF.createInstance( "com.sun.star.text.TextTable" ) );
xTextTable.initialize( 2, 2); // rows, cols

// insert table  in the xText
xText.insertTextContent(xText.getEnd(), xTextTable, false);

Now to add data to the cells in table

XCellRange xCellRangeHeader = (XCellRange) UnoRuntime.queryInterface(XCellRange.class, table);
XCell xCellHeader = null;
XText xHeaderText = null;

xCellHeader = xCellRangeHeader.getCellByPosition(0, 0); // cols, rows
xHeaderText = (XText) UnoRuntime.queryInterface(XText.class, xCellHeader);
xHeaderText.setString("A1");

xCellHeader = xCellRangeHeader.getCellByPosition(1, 0); // cols, rows
xHeaderText = (XText) UnoRuntime.queryInterface(XText.class, xCellHeader);
xHeaderText.setString("A2"); 

xCellHeader = xCellRangeHeader.getCellByPosition(0, 1); // cols, rows
xHeaderText = (XText) UnoRuntime.queryInterface(XText.class, xCellHeader);
xHeaderText.setString("B1"); 

xCellHeader = xCellRangeHeader.getCellByPosition(1, 1); // cols, rows
xHeaderText = (XText) UnoRuntime.queryInterface(XText.class, xCellHeader);
xHeaderText.setString("B2"); 

Paper Formating

The default paper format and orientation is A4 and portrait. To change paper orientation

XPrintable xPrintable = ( XPrintable ) UnoRuntime.queryInterface(XPrintable.class, document);
PropertyValue[] printerDesc = new PropertyValue[2];

// Paper Orientation           
printerDesc[0] = new PropertyValue();
printerDesc[0].Name = "PaperOrientation";
printerDesc[0].Value = PaperOrientation.LANDSCAPE;

// Paper Format           
printerDesc[1] = new PropertyValue();
printerDesc[1].Name = "PaperFormat";
printerDesc[1].Value = PaperFormat.A3;

xPrintable.setPrinter(printerDesc);

Saving the Document

The final task is to save the document. Here is the code to do that

// the url where the document is to be saved
String storeUrl = “file:///tmp/OOo_doc.odt";

// Save the document
XStorable xStorable = ( XStorable )UnoRuntime.queryInterface(XStorable.class, document);
PropertyValue[] storeProps = new PropertyValue[0];
xStorable.storeAsURL(storeUrl, storeProps);

When you want to export it to PDF, you need to specify a filter name: writer_pdf_Export. Also note that you need to call storeToUrl instead of storeAsUrl, otherwise you’ll get the following exception: com.sun.star.task.ErrorCodeIOException.

// export document to pdf
storeProps = new PropertyValue[1];
storeProps[0] = new PropertyValue();
storeProps[0].Name = "FilterName";
storeProps[0].Value = "writer_pdf_Export";

xStorable.storeToURL(“file:///tmp/OOo_doc.pdf", storeProps);

We can also save the document in other formats by specifying the filter name. For example, to save to rich text format

// the url where the document is to be saved
String storeUrl = “file:///tmp/OOo_doc.rtf ";

// Save the document
XStorable xStorable = ( XStorable )UnoRuntime.queryInterface(XStorable.class, document);
PropertyValue[] storeProps = new PropertyValue[0];
storeProps[0] = new PropertyValue();
storeProps[0].Name = "FilterName";
storeProps[0].Value = "Rich Text Format";

xStorable.storeAsURL(storeUrl, storeProps);

Printing the Document

Of course the document could be send to a printer. Here is the code to do that

XPrintable xPrintable = (XPrintable)UnoRuntime.queryInterface(XPrintable.class, document);
PropertyValue[] printerDesc = new PropertyValue[1];
printerDesc[0] = new PropertyValue();
printerDesc[0].Name = "Name";
printerDesc[0].Value = "PDFCreator";
xPrintable.setPrinter(printerDesc);

PropertyValue[] printOpts = new PropertyValue[1];
printOpts[0] = new PropertyValue();
printOpts[0].Name = "Pages";
printOpts[0].Value = "1";
xPrintable.print(printOpts);

Now we can close the document

// close document
XCloseable xcloseable = (XCloseable) UnoRuntime.queryInterface(XCloseable.class, document);
xcloseable.close(false);