8194922: jlink --exclude-resources should never exclude module-info.class

Reviewed-by: alanb

src/jdk.jlink/share/classes/jdk/tools/jlink/internal/plugins/ExcludePlugin.java

@@ -27,6 +27,7 @@ package jdk.tools.jlink.internal.plugins;
 import java.util.Map;
 import java.util.function.Predicate;
 import jdk.tools.jlink.plugin.Plugin;
+import jdk.tools.jlink.plugin.PluginException;
 import jdk.tools.jlink.plugin.ResourcePool;
 import jdk.tools.jlink.plugin.ResourcePoolBuilder;
 import jdk.tools.jlink.plugin.ResourcePoolEntry;
@@ -49,7 +50,13 @@ public final class ExcludePlugin implements Plugin {
     public ResourcePool transform(ResourcePool in, ResourcePoolBuilder out) {
         in.transformAndCopy((resource) -> {
             if (resource.type().equals(ResourcePoolEntry.Type.CLASS_OR_RESOURCE)) {
-                resource = predicate.test(resource.path()) ? resource : null;
+                boolean shouldExclude = !predicate.test(resource.path());
+                // do not allow filtering module-info.class to avoid mutating module graph.
+                if (shouldExclude &&
+                    resource.path().equals("/" + resource.moduleName() + "/module-info.class")) {
+                    throw new PluginException("Cannot exclude " + resource.path());
+                }
+                return shouldExclude? null : resource;
             }
             return resource;
         }, out);

test/jdk/tools/jlink/JLinkTest.java

@@ -43,6 +43,7 @@ import tests.JImageGenerator;
  * @test
  * @summary Test image creation
  * @bug 8189777
+ * @bug 8194922
  * @author Jean-Francois Denise
  * @requires (vm.compMode != "Xcomp" & os.maxMemory >= 2g)
  * @library ../lib
@@ -276,6 +277,15 @@ public class JLinkTest {
             helper.checkImage(imageDir, moduleName, res, null);
         }
 
+        // module-info.class should not be excluded
+        {
+            String[] userOptions = { "--exclude-resources", "/jdk_8194922/module-info.class" };
+            String moduleName = "jdk_8194922";
+            helper.generateDefaultJModule(moduleName);
+            helper.generateDefaultImage(userOptions, moduleName).
+                assertFailure("Cannot exclude /jdk_8194922/module-info.class");
+        }
+
         // default compress
         {
             testCompress(helper, "compresscmdcomposite2", "--compress", "2");

test/jdk/tools/jlink/plugins/ExcludeModuleInfoTest.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8194922
+ * @summary jlink --exclude-resources should never exclude module-info.class
+ * @modules jdk.jlink/jdk.tools.jlink.internal
+ *          jdk.jlink/jdk.tools.jlink.internal.plugins
+ *          jdk.jlink/jdk.tools.jlink.plugin
+ * @run main ExcludeModuleInfoTest
+ */
+
+import java.io.File;
+import java.nio.file.Files;
+import java.util.HashMap;
+import java.util.Map;
+import jdk.tools.jlink.internal.ResourcePoolManager;
+
+import jdk.tools.jlink.internal.plugins.ExcludePlugin;
+import jdk.tools.jlink.plugin.PluginException;
+import jdk.tools.jlink.plugin.ResourcePool;
+import jdk.tools.jlink.plugin.ResourcePoolBuilder;
+import jdk.tools.jlink.plugin.ResourcePoolEntry;
+
+public class ExcludeModuleInfoTest {
+
+    public static void main(String[] args) throws Exception {
+        new ExcludeModuleInfoTest().test();
+    }
+
+    public void test() throws Exception {
+        check("**.class", "/mymodule/module-info.class");
+        check("/java.base/module-info.class", "/java.base/module-info.class");
+    }
+
+    public void check(String s, String sample) throws Exception {
+        Map<String, String> prop = new HashMap<>();
+        prop.put(ExcludePlugin.NAME, s);
+        ExcludePlugin excludePlugin = new ExcludePlugin();
+        excludePlugin.configure(prop);
+        ResourcePoolManager resourcesMgr = new ResourcePoolManager();
+        ResourcePoolEntry resource = ResourcePoolEntry.create(sample, new byte[0]);
+        resourcesMgr.add(resource);
+        ResourcePoolManager resultMgr = new ResourcePoolManager();
+        try {
+            excludePlugin.transform(resourcesMgr.resourcePool(),
+                resultMgr.resourcePoolBuilder());
+            throw new AssertionError(sample + " exclusion should have resulted in exception");
+        } catch (PluginException pe) {
+            System.err.println("Got exception as expected: " + pe);
+            pe.printStackTrace();
+        }
+    }
+}