Fix the load for no lib case.

Author: amamounelsayed

src/main/java/com/microsoft/azure/functions/worker/broker/JavaFunctionBroker.java

@@ -89,7 +89,33 @@ public Map<String, TypedData> getTriggerMetadataMap(InvocationRequest request) {
 	private void addSearchPathsToClassLoader(FunctionMethodDescriptor function) throws IOException {
 		URL jarUrl = new File(function.getJarPath()).toURI().toURL();
 		classLoaderProvider.addUrl(jarUrl);
-		function.getLibDirectory().ifPresent(d -> registerWithClassLoaderProvider(d));
+		if(function.getLibDirectory().isPresent()) {
+			registerWithClassLoaderProvider(function.getLibDirectory().get());
+		} else {
+			registerWithClassLoaderProviderWorkerLibOnly();
+		}
+	}
+
+	void registerWithClassLoaderProviderWorkerLibOnly() {
+		try {
+			if(SystemUtils.IS_JAVA_1_8 && !isTesting()) {
+				String workerLibPath = System.getenv(Constants.FUNCTIONS_WORKER_DIRECTORY) + "/lib";
+				File workerLib = new File(workerLibPath);
+				verifyLibrariesExist (workerLib, workerLibPath);
+				classLoaderProvider.addDirectory(workerLib);
+			}
+		} catch (Exception ex) {
+			ExceptionUtils.rethrow(ex);
+		}
+	}
+
+	private boolean isTesting(){
+		if(System.getProperty("azure.functions.worker.java.skip.testing") != null
+				&& System.getProperty("azure.functions.worker.java.skip.testing").equals("true")) {
+			return true;
+		} else {
+			return false;
+		}
 	}
 
 	void registerWithClassLoaderProvider(File libDirectory) {

src/test/java/com/microsoft/azure/functions/worker/broker/JavaFunctionBrokerTest.java

@@ -4,6 +4,7 @@
 import com.microsoft.azure.functions.rpc.messages.ParameterBinding;
 import com.microsoft.azure.functions.rpc.messages.TypedData;
 import com.microsoft.azure.functions.worker.broker.JavaFunctionBroker;
+import com.microsoft.azure.functions.worker.description.FunctionMethodDescriptor;
 import com.microsoft.azure.functions.worker.reflect.DefaultClassLoaderProvider;
 import mockit.*;
 import org.junit.Test;
@@ -123,4 +124,10 @@ public void checkLibFolderNoJarsInLib() throws Exception {
         File file = new File(path);
         broker.verifyLibrariesExist (file, path);
     }
+
+    @Test(expected = FileNotFoundException.class)
+    public void registerWithClassLoaderProviderWorkerLibOnly_Exception() throws Exception {
+        JavaFunctionBroker broker = new JavaFunctionBroker(null);
+        broker.registerWithClassLoaderProviderWorkerLibOnly();
+    }
 }

src/test/java/com/microsoft/azure/functions/worker/functional/tests/SimpleParamReturnTest.java

@@ -28,6 +28,7 @@ public String ReturnStringFunction() {
 	@Test
 	public void testStringData() throws Exception {
 		stringReturnValue = stringInput;
+		System.setProperty("azure.functions.worker.java.skip.testing", "true");
 		try (FunctionsTestHost host = new FunctionsTestHost()) {
 			this.loadFunction(host, "returnStringTestId", "ReturnStringFunction");
 			InvocationResponse stringResponse = host.call("getret", "returnStringTestId");