8273092: Sort classlist in JDK image

Reviewed-by: redestad, ihse, dfuchs

make/GenerateLinkOptData.gmk

@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2016, 2020, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2016, 2021, 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
@@ -88,7 +88,10 @@ $(CLASSLIST_FILE): $(INTERIM_IMAGE_DIR)/bin/java$(EXECUTABLE_SUFFIX) $(CLASSLIST
 	        $(CAT) $(LINK_OPT_DIR)/stderr $(JLI_TRACE_FILE) ; \
 	        exit $$exitcode \
 	    )
-	$(GREP) -v HelloClasslist $@.raw.2 > $@
+	$(GREP) -v HelloClasslist $@.raw.2 > $@.raw.3
+	$(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java \
+	    -cp $(SUPPORT_OUTPUTDIR)/classlist.jar \
+	    build.tools.classlist.SortClasslist $@.raw.3 > $@
 
 # The jli trace is created by the same recipe as classlist. By declaring these
 # dependencies, make will correctly rebuild both jli trace and classlist

make/jdk/src/classes/build/tools/classlist/SortClasslist.java

@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2021, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+
+/**
+ * This application is meant to be run to create a classlist file representing
+ * common use.
+ *
+ * The classlist is produced by adding -XX:DumpLoadedClassList=classlist
+ */
+package build.tools.classlist;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.regex.Pattern;
+import java.util.regex.Matcher;
+import java.util.Scanner;
+
+/**
+ * The classlist generated by build.tools.classlist.HelloClasslist
+ * may have non-deterministic contents, affected by Java thread execution order.
+ * SortClasslist sorts the file to make the JDK image's contents more deterministic.
+ */
+public class SortClasslist {
+    public static void main(String args[]) throws FileNotFoundException  {
+        ArrayList<String> classes = new ArrayList<>();
+        ArrayList<String> lambdas = new ArrayList<>();
+
+        FileInputStream fis = new FileInputStream(args[0]);
+        Scanner scanner = new Scanner(fis);
+        Pattern p = Pattern.compile("^(.*)[ ]+id:[ ]+([0-9]+)$");
+        while (scanner.hasNextLine()) {
+            String line = scanner.nextLine();
+            Matcher m = p.matcher(line);
+            if (line.startsWith("#")) {
+                // Comments -- print them first without sorting. These appear only at the top
+                // of the file.
+                System.out.println(line);
+            } else if (line.startsWith("@")) {
+                // @lambda-form-invoker, @lambda-proxy, etc.
+                lambdas.add(line);
+            } else if (m.find()) {
+                // We found a pattern like this:
+                //
+                //    <beginning of line>java/lang/Object id: 0<end of line>
+                //
+                // This is a class used by one of the three builtin class loaders
+                // (boot/platform/app). Since the default classlist does not support unregistered
+                // classes, the ID is unused. Let's omit the ID, as it may be non-deterministic.
+                String className = m.group(1); // matches the (.*) part of the pattern.
+                classes.add(className);
+            } else {
+                // HelloClasslist should not load classes in custom class loaders, or else
+                // we might end up with output like this:
+                //
+                //     SomeClass id: 123 super: 0 source: foo.jar
+                //
+                // Such classes won't be usable for common applications, so they should
+                // not be included in the JDK's default classlist.
+                System.err.println("Unexpected line: " + line);
+                System.err.println("The default classlist should not contain unregistered classes");
+                System.exit(1);
+            }
+        }
+
+        Collections.sort(classes);
+        Collections.sort(lambdas);
+
+        for (String s : classes) {
+            System.out.println(s);
+        }
+        for (String s : lambdas) {
+            System.out.println(s);
+        }
+    }
+}

make/scripts/compare.sh

@@ -356,20 +356,14 @@ compare_general_files() {
                     "
                 $CAT $OTHER_DIR/$f | eval "$SVG_FILTER" > $OTHER_FILE
                 $CAT $THIS_DIR/$f | eval "$SVG_FILTER" > $THIS_FILE
-            elif [[ "$f" = *"/lib/classlist" ]] || [ "$SUFFIX" = "jar_contents" ]; then
-                # The classlist files may have some lines in random order
+            elif [ "$SUFFIX" = "jar_contents" ]; then
+                # The jar_contents files may have some lines in random order
                 OTHER_FILE=$WORK_DIR/$f.other
                 THIS_FILE=$WORK_DIR/$f.this
                 $MKDIR -p $(dirname $OTHER_FILE) $(dirname $THIS_FILE)
                 $RM $OTHER_FILE $THIS_FILE
-                # Also filter out the "id: NNNN" in the classlists
-                if [[ "$f" = *"/lib/classlist" ]]; then
-                    $CAT $OTHER_DIR/$f | $SORT | $SED "s| id: .*||g" > $OTHER_FILE
-                    $CAT $THIS_DIR/$f  | $SORT | $SED "s| id: .*||g" > $THIS_FILE
-                else
-                    $CAT $OTHER_DIR/$f | $SORT > $OTHER_FILE
-                    $CAT $THIS_DIR/$f  | $SORT > $THIS_FILE
-                fi
+                $CAT $OTHER_DIR/$f | $SORT > $OTHER_FILE
+                $CAT $THIS_DIR/$f  | $SORT > $THIS_FILE
             else
                 OTHER_FILE=$OTHER_DIR/$f
                 THIS_FILE=$THIS_DIR/$f