Hello World!! written JavaScript for Libreoffice Macro

Macro1.js

importClass(Packages.com.sun.star.uno.UnoRuntime);
importClass(Packages.javax.swing.JOptionPane);
importClass(Packages.com.sun.star.sheet.XSpreadsheetDocument);
importClass(Packages.com.sun.star.frame.XModel);
importClass(Packages.com.sun.star.container.XIndexAccess);
importClass(Packages.com.sun.star.table.XCellRange);
importClass(Packages.com.sun.star.table.XCell);

// get Document Object
var doc = UnoRuntime.queryInterface(
	XModel,
	XSCRIPTCONTEXT.getInvocationContext()
);
if ( !doc ) doc = XSCRIPTCONTEXT.getDocument();

// get Spreadsheet Document
var sDoc = UnoRuntime.queryInterface(XSpreadsheetDocument,doc);
if ( sDoc ){
	//get Accesser for sheet group
	var sheetsIndexAccess = UnoRuntime.queryInterface(
		XIndexAccess,
		sDoc.getSheets()
	);
	// get first sheet object
	var sheet = sheetsIndexAccess.getByIndex(0);
	// get cell range object
	var cells = UnoRuntime.queryInterface(XCellRange, sheet);
	// get cell object
	var cell = cells.getCellByPosition(0,0);
	// get Accesser for cell
	var accscell = UnoRuntime.queryInterface(XCell,cell);
	accscell.setFormula("Hello World!!");
	JOptionPane.showMessageDialog(
		null,
		accscell.getFormula()
	);
}