--- /dev/null
+package org.argeo.cms.e4;
+
+import org.argeo.cms.swt.CmsException;
+import org.eclipse.e4.core.contexts.ContextFunction;
+import org.eclipse.e4.core.contexts.IEclipseContext;
+import org.eclipse.e4.core.di.IInjector;
+import org.osgi.framework.BundleContext;
+import org.osgi.framework.FrameworkUtil;
+import org.osgi.framework.InvalidSyntaxException;
+import org.osgi.framework.ServiceReference;
+
+/** An Eclipse 4 {@link ContextFunction} based on an OSGi filter. */
+public class OsgiFilterContextFunction extends ContextFunction {
+
+ private BundleContext bc = FrameworkUtil.getBundle(OsgiFilterContextFunction.class).getBundleContext();
+
+ @Override
+ public Object compute(IEclipseContext context, String contextKey) {
+ ServiceReference<?>[] srs;
+ try {
+ srs = bc.getServiceReferences((String) null, contextKey);
+ } catch (InvalidSyntaxException e) {
+ throw new CmsException("Context key " + contextKey + " must be a valid osgi filter", e);
+ }
+ if (srs == null || srs.length == 0) {
+ return IInjector.NOT_A_VALUE;
+ } else {
+ // return the first one
+ return bc.getService(srs[0]);
+ }
+ }
+
+}