Add parent class loader entries if possible

...otherwise you can see cryptic NoClassDefFound errors
because the application class was loaded from the parent
on the file system, but then it doesn't have access to the
child loaders nested jars.

spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/PropertiesLauncher.java

@@ -21,7 +21,9 @@ import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.HttpURLConnection;
+import java.net.URISyntaxException;
 import java.net.URL;
+import java.net.URLClassLoader;
 import java.net.URLConnection;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -34,6 +36,7 @@ import org.springframework.boot.loader.archive.Archive;
 import org.springframework.boot.loader.archive.Archive.Entry;
 import org.springframework.boot.loader.archive.Archive.EntryFilter;
 import org.springframework.boot.loader.archive.ExplodedArchive;
+import org.springframework.boot.loader.archive.JarFileArchive;
 import org.springframework.boot.loader.util.SystemPropertyUtils;
 
 /**
@@ -318,9 +321,26 @@ public class PropertiesLauncher extends Launcher {
 				this.logger.info("No directory found at " + path);
 			}
 		}
+		addParentClassLoaderEntries(lib);
 		return lib;
 	}
 
+	private void addParentClassLoaderEntries(List<Archive> lib) throws IOException,
+			URISyntaxException {
+		ClassLoader parentClassLoader = getClass().getClassLoader();
+		if (parentClassLoader instanceof URLClassLoader) {
+			URLClassLoader urlClassLoader = (URLClassLoader) parentClassLoader;
+			for (URL url : urlClassLoader.getURLs()) {
+				if (url.toString().endsWith(".jar") || url.toString().endsWith(".zip")) {
+					lib.add(0, new JarFileArchive(new File(url.toURI())));
+				}
+				else {
+					lib.add(0, new ExplodedArchive(new File(url.getFile())));
+				}
+			}
+		}
+	}
+
 	private String cleanupPath(String path) {
 		path = path.trim();
 		// Always a directory