Update quickstart example with a bug fix.

Signed-off-by: Rahul Krishna <i.m.ralk@gmail.com>

Author: rahlk

src/main/java/com/ibm/cldk/utils/BuildProject.java

@@ -274,14 +274,14 @@ public static void cleanLibraryDependencies() {
                 Files.walk(libDownloadPath).filter(Files::isRegularFile).map(Path::toFile).forEach(File::delete);
                 Files.delete(libDownloadPath);
             } catch (IOException e) {
-                Log.error("Error deleting library dependency directory: " + e.getMessage());
+                Log.warn("Unable to fully delete library dependency directory: " + e.getMessage());
             }
         }
         if (tempInitScript != null) {
             try {
                 Files.delete(tempInitScript);
             } catch (IOException e) {
-                Log.error("Error deleting temporary Gradle init script: " + e.getMessage());
+                Log.warn("Error deleting temporary Gradle init script: " + e.getMessage());
             }
         }
     }

src/main/java/com/ibm/cldk/utils/ProjectDirectoryScanner.java

@@ -7,6 +7,8 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
 
 public class ProjectDirectoryScanner {
     public static List<Path> classFilesStream(String projectPath) throws IOException {
@@ -37,6 +39,30 @@ public static List<Path> jarFilesStream(String projectPath) throws IOException {
         return null;
     }
 
+    /**
+     * Returns a stream of class files inside the jars and class files in the project.
+     * @param projectPath
+     * @return
+     * @throws IOException
+     */
+    public static Stream<String> classesFromJarFileStream(String projectPath) throws IOException {
+        List<Path> jarPaths = jarFilesStream(projectPath);
+
+        if (jarPaths == null) {
+            return Stream.empty();
+        }
+
+        return jarPaths.stream().flatMap(jarPath -> {
+            try (ZipFile zip = new ZipFile(jarPath.toFile())) {
+                return zip.stream()
+                        .filter(entry -> !entry.isDirectory() && entry.getName().endsWith(".class"))
+                        .map(ZipEntry::getName);
+            } catch (IOException e) {
+                return Stream.empty();
+            }
+        });
+    }
+
     public static List<Path> sourceFilesStream(String projectPath) throws IOException {
         Path projectDir = Paths.get(projectPath);
         Log.info("Finding *.java files in " + projectDir);