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Sometimes an extension developer needs to know the path to the root of his installed extension e.g. to load some additional data. You can use the singleton PackageInformationProvider to get an URL for an installed extension with a given Extension Identifier. For more information about Extension Identifiers see Extension Identifiers. For more information see the singleton com.sun.star.deployment.PackageInformationProvider and its interface com.sun.star.deployment.XPackageInformationProvider.

Here is a C++ example:

  ...
  namespace css = com::sun::star;
  css::uno::Reference< css::uno::XComponentContext > mxContext;
  ...
  css::uno::Reference< css::deployment::XPackageInformationProvider >
  xInfoProvider( css::deployment::PackageInformationProvider::get( mxContext ) );
 
  // "MY_PACKAGE_ID" is the identifier of the package whose location we want
  rtl::OUString sLocation = xInfoProvider->getPackageLocation( 
  rtl::OUString::createFromAscii( "MY_PACKAGE_ID" ) );
  ...

You will find a Java example at page : ReadFilesFromOxt

Here is an example in Basic:

Dim pip As Object, extensionLocation As String
Const extensionIdentifier = "org.toto.test3"
 
pip = GetDefaultContext.getByName("/singletons/com.sun.star.deployment.PackageInformationProvider")
extensionLocation = pip.getPackageLocation(extensionIdentifier)
' display a human readable address
MsgBox(ConvertFromURL(extensionLocation))

The package location address finishes like this : /extensionName.oxt Remember it is a folder, not the extension package itself!