Use Bundle#getResources to discover embedded SPI resources

Currently we use bundle.getEntry but this has some limitations, e.g.
fragments and embedded jars.

While the first can be avoided with findEntries, the second can not. As
we previously already used bundle.getResources it seems fine to continue
using that method.

Author: laeubi

ui/org.eclipse.pde.junit.runtime/src/org/eclipse/pde/internal/junit/runtime/SPIBundleClassLoader.java

@@ -89,21 +89,23 @@ protected Enumeration<URL> findResources(String name) throws IOException {
 			List<SPIMapping> spis = mappings.computeIfAbsent(name, spi -> {
 				List<SPIMapping> list = new ArrayList<>();
 				for (Bundle other : bundles) {
-					URL entry = other.getEntry(name);
-					if (entry != null) {
-						try {
-							list.add(new SPIMapping(other.loadClass(serviceName), other, entry));
-						} catch (ClassNotFoundException e) {
-							// should not happen
+					try {
+						Enumeration<URL> resources = other.getResources(name);
+						if (resources != null) {
+							list.add(new SPIMapping(other.loadClass(serviceName), other, Collections.list(resources)));
 						}
+					} catch (ClassNotFoundException e) {
+						// should not happen
+					} catch (IOException e) {
+						//can't be used then
 					}
 				}
 				return list;
 			});
 			Bundle caller = Caller.getBundle(junitVersion);
 			for (SPIMapping mapping : spis) {
 				if (mapping.isCompatible(caller)) {
-					result.add(mapping.getUrl());
+					result.addAll(mapping.getUrls());
 				}
 			}
 			return Collections.enumeration(result);

ui/org.eclipse.pde.junit.runtime/src/org/eclipse/pde/internal/junit/runtime/SPIMapping.java

@@ -17,9 +17,9 @@
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.URL;
-import java.util.HashSet;
+import java.util.Collection;
+import java.util.LinkedHashSet;
 import java.util.Set;
-import java.util.stream.Collectors;
 
 import org.osgi.framework.Bundle;
 
@@ -28,23 +28,27 @@ final class SPIMapping {
 	private final Class<?> serviceClass;
 	private final Bundle bundle;
 	private final Set<String> classes;
-	private final URL url;
+	private final Collection<URL> urls;
 
-	SPIMapping(Class<?> serviceClass, Bundle bundle, URL url) {
+	SPIMapping(Class<?> serviceClass, Bundle bundle, Collection<URL> urls) {
 		this.serviceClass = serviceClass;
 		this.bundle = bundle;
-		this.url = url;
-		this.classes = readClasses(url);
+		this.urls = urls;
+		this.classes = readClasses(urls);
 	}
 
-	private Set<String> readClasses(URL entry) {
-		try (BufferedReader reader = new BufferedReader(new InputStreamReader(entry.openStream()))) {
-			return reader.lines().collect(Collectors.toSet());
-		} catch (IOException e) {
-			return new HashSet<>();
+	private static Set<String> readClasses(Collection<URL> urls) {
+		Set<String> result = new LinkedHashSet<>();
+		for (URL url : urls) {
+			try (BufferedReader reader = new BufferedReader(new InputStreamReader(url.openStream()))) {
+				reader.lines().forEach(result::add);
+			} catch (IOException e) {
+			}
 		}
+		return result;
 	}
 
+
 	boolean isCompatible(Bundle other) {
 		try {
 			return other.loadClass(serviceClass.getName()) == serviceClass;
@@ -53,8 +57,8 @@ boolean isCompatible(Bundle other) {
 		}
 	}
 
-	URL getUrl() {
-		return url;
+	Collection<URL> getUrls() {
+		return urls;
 	}
 
 	boolean hasService(String implementation) {