8366040: Change URL.lookupViaProviders to use ScopedValue to detect recursive lookup

Reviewed-by: alanb, dfuchs

src/java.base/share/classes/java/net/URL.java

@@ -41,7 +41,6 @@ import java.util.ServiceLoader;
 
 import jdk.internal.access.JavaNetURLAccess;
 import jdk.internal.access.SharedSecrets;
-import jdk.internal.misc.ThreadTracker;
 import jdk.internal.misc.VM;
 import jdk.internal.vm.annotation.AOTRuntimeSetup;
 import jdk.internal.vm.annotation.AOTSafeClassInitializer;
@@ -1394,24 +1393,13 @@ public final class URL implements java.io.Serializable {
         return handler;
     }
 
-    private static class ThreadTrackHolder {
-        static final ThreadTracker TRACKER = new ThreadTracker();
-    }
-
-    private static Object tryBeginLookup() {
-        return ThreadTrackHolder.TRACKER.tryBegin();
-    }
-
-    private static void endLookup(Object key) {
-        ThreadTrackHolder.TRACKER.end(key);
-    }
+    private static final ScopedValue<Boolean> IN_LOOKUP = ScopedValue.newInstance();
 
     private static URLStreamHandler lookupViaProviders(final String protocol) {
-        Object key = tryBeginLookup();
-        if (key == null) {
+        if (IN_LOOKUP.isBound()) {
             throw new Error("Circular loading of URL stream handler providers detected");
         }
-        try {
+        return ScopedValue.where(IN_LOOKUP, true).call(() -> {
             final ClassLoader cl = ClassLoader.getSystemClassLoader();
             final ServiceLoader<URLStreamHandlerProvider> sl =
                     ServiceLoader.load(URLStreamHandlerProvider.class, cl);
@@ -1423,9 +1411,7 @@ public final class URL implements java.io.Serializable {
                     return h;
             }
             return null;
-        } finally {
-            endLookup(key);
-        }
+        });
     }
 
     /**

test/jdk/java/net/spi/URLStreamHandlerProvider/Basic.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2025, 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
@@ -77,6 +77,7 @@ public class Basic {
         viaProvider("bert", KNOWN);
         viaBadProvider("tom", SCE);
         viaBadProvider("jerry", SCE);
+        viaCircularProvider("circular", CIRCULAR);
     }
 
     private static String withoutWarning(String in) {
@@ -99,6 +100,12 @@ public class Basic {
             throw new RuntimeException("exitValue: "+ r.exitValue + ", output:[" +r.output +"]");
         }
     };
+    static final Consumer<Result> CIRCULAR = r -> {
+        if (r.exitValue == 0 ||
+            !r.output.contains("Circular loading of URL stream handler providers detected")) {
+            throw new RuntimeException("exitValue: " + r.exitValue + ", output:[" + r.output + "]");
+        }
+    };
 
     static void unknownProtocol(String protocol, Consumer<Result> resultChecker) {
         System.out.println("\nTesting " + protocol);
@@ -125,6 +132,15 @@ public class Basic {
                                 sysProps);
     }
 
+    static void viaCircularProvider(String protocol, Consumer<Result> resultChecker,
+                                    String... sysProps)
+        throws Exception
+    {
+        viaProviderWithTemplate(protocol, resultChecker,
+                                TEST_SRC.resolve("circular.provider.template"),
+                                sysProps);
+    }
+
     static void viaProviderWithTemplate(String protocol,
                                         Consumer<Result> resultChecker,
                                         Path template, String... sysProps)

test/jdk/java/net/spi/URLStreamHandlerProvider/circular.provider.template

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2025, 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.
+ */
+
+package $package;
+
+import java.io.IOException;
+import java.net.URI;
+import java.net.URL;
+import java.net.URLConnection;
+import java.net.URLStreamHandler;
+import java.net.spi.URLStreamHandlerProvider;
+
+public final class Provider extends URLStreamHandlerProvider {
+
+    private static final String PROTOCOL = "$protocol";
+
+    @Override
+    public URLStreamHandler createURLStreamHandler(String protocol) {
+        try {
+            // Trigger circular lookup
+            URI.create("bogus://path/to/nothing").toURL();
+        } catch (Exception exception) {
+            throw new RuntimeException(exception);
+        }
+        throw new AssertionError("Should not have reached here!");
+    }
+
+}