#1981: Optional OSGi bundle's dependency on sun.misc package (#1993)

* #1981: Avoid OSGi bundle's dependency on sun.misc package

* Specify optional dependency on sun.misc.Unsafe

* Adjusting the test to sun.misc import being optional

* Using Collections.list and for loop

* Let the fail message include name of package

Co-authored-by: Marcono1234 <Marcono1234@users.noreply.github.com>

* Closing the input stream

* Dedicated assertSubstring method

Co-authored-by: Marcono1234 <Marcono1234@users.noreply.github.com>

gson/bnd.bnd

@@ -6,6 +6,10 @@ Bundle-ContactAddress: ${project.parent.url}
 Bundle-RequiredExecutionEnvironment: JavaSE-1.6, JavaSE-1.7, JavaSE-1.8
 Require-Capability: osgi.ee;filter:="(&(osgi.ee=JavaSE)(version=1.6))"
 
+# Optional dependency for JDK's sun.misc.Unsafe
+# https://bnd.bndtools.org/chapters/920-faq.html#remove-unwanted-imports-
+Import-Package: sun.misc;resolution:=optional, *
+
 -removeheaders: Private-Package
 
 -exportcontents:\

gson/src/main/java/module-info.java

@@ -10,4 +10,7 @@
 
 	// Optional dependency on java.sql
 	requires static java.sql;
+
+	// Optional dependency on jdk.unsupported for JDK's sun.misc.Unsafe
+	requires static jdk.unsupported;
 }

gson/src/test/java/com/google/gson/regression/OSGiTest.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2016 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.gson.regression;
+
+import java.io.InputStream;
+import java.io.IOException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.jar.Manifest;
+
+import junit.framework.TestCase;
+
+public class OSGiTest extends TestCase {
+    public void testComGoogleGsonAnnotationsPackage() throws Exception {
+        Manifest mf = findManifest("com.google.gson");
+        String importPkg = mf.getMainAttributes().getValue("Import-Package");
+        assertNotNull("Import-Package statement is there", importPkg);
+        assertSubstring("There should be com.google.gson.annotations dependency", importPkg, "com.google.gson.annotations");
+    }
+
+    public void testSunMiscImportPackage() throws Exception {
+        Manifest mf = findManifest("com.google.gson");
+        String importPkg = mf.getMainAttributes().getValue("Import-Package");
+        assertNotNull("Import-Package statement is there", importPkg);
+        for (String dep : importPkg.split(",")) {
+            if (dep.contains("sun.misc")) {
+                assertSubstring("sun.misc import is optional", dep, "resolution:=optional");
+                return;
+            }
+        }
+        fail("There should be sun.misc dependency, but was: " + importPkg);
+    }
+
+    private Manifest findManifest(String pkg) throws IOException {
+        List<URL> urls = new ArrayList<URL>();
+        for (URL u : Collections.list(getClass().getClassLoader().getResources("META-INF/MANIFEST.MF"))) {
+            InputStream is = u.openStream();
+            Manifest mf = new Manifest(is);
+            is.close();
+            if (pkg.equals(mf.getMainAttributes().getValue("Bundle-SymbolicName"))) {
+                return mf;
+            }
+            urls.add(u);
+        }
+        fail("Cannot find " + pkg + " OSGi bundle manifest among: " + urls);
+        return null;
+    }
+
+    private static void assertSubstring(String msg, String wholeText, String subString) {
+        if (wholeText.contains(subString)) {
+            return;
+        }
+        fail(msg + ". Expecting " + subString + " but was: " + wholeText);
+    }
+}