fixes

Author: simbo1905

json-java21-schema/src/main/java/io/github/simbo1905/json/schema/JsonSchema.java

@@ -663,9 +663,9 @@ static boolean scheduleRemoteIfUnseen(Deque<java.net.URI> workStack,
 
     // Detect remote cycles by walking parent chain
     if (formsRemoteCycle(parentMap, currentDocUri, targetDocUri)) {
-      String cycleMessage = "ERROR: CYCLE: remote $ref cycle current=" + currentDocUri + ", target=" + targetDocUri;
+      String cycleMessage = "ERROR: CYCLE: remote $ref cycle detected current=" + currentDocUri + ", target=" + targetDocUri;
       LOG.severe(() -> cycleMessage);
-      throw new IllegalArgumentException(cycleMessage);
+      throw new IllegalStateException(cycleMessage);
     }
 
     // Check if already built or already in work stack
@@ -1995,9 +1995,9 @@ private static JsonSchema compileInternalWithContext(Session session, JsonValue
             LOG.fine(() -> "Remote ref scheduling from docUri=" + docUri + " to target=" + targetDocUri);
             LOG.finest(() -> "Remote ref parentMap before cycle check: " + session.parentMap);
             if (formsRemoteCycle(session.parentMap, docUri, targetDocUri)) {
-              String cycleMessage = "ERROR: CYCLE: remote $ref cycle current=" + docUri + ", target=" + targetDocUri;
+              String cycleMessage = "ERROR: CYCLE: remote $ref cycle detected current=" + docUri + ", target=" + targetDocUri;
               LOG.severe(() -> cycleMessage);
-              throw new IllegalArgumentException(cycleMessage);
+              throw new IllegalStateException(cycleMessage);
             }
             boolean alreadySeen = seenUris.contains(targetDocUri);
             LOG.finest(() -> "Remote ref alreadySeen=" + alreadySeen + " for target=" + targetDocUri);

json-java21-schema/src/test/java/io/github/simbo1905/json/schema/JsonSchemaRemoteRefTest.java

@@ -303,7 +303,7 @@ void detects_cross_document_cycle() {
                 """),
                 JsonSchema.Options.DEFAULT,
                 options
-            )).isInstanceOf(IllegalArgumentException.class)
+            )).isInstanceOf(IllegalStateException.class)
                 .hasMessageContaining("ERROR: CYCLE: remote $ref cycle");
             assertThat(logs.lines().stream().anyMatch(line -> line.startsWith("ERROR: CYCLE:"))).isTrue();
         }

json-java21-schema/src/test/java/io/github/simbo1905/json/schema/JsonSchemaRemoteServerRefTest.java

@@ -25,16 +25,17 @@ void resolves_pointer_inside_remote_doc_via_http() {
     }
 
     @Test
-    void remote_cycle_handles_gracefully() {
+    void remote_cycle_detected_and_throws() {
         var policy = JsonSchema.FetchPolicy.defaults().withAllowedSchemes(Set.of("http","https"));
         var options = JsonSchema.CompileOptions.remoteDefaults(new VirtualThreadHttpFetcher()).withFetchPolicy(policy);
 
-        // Compilation should succeed despite the cycle
-        var compiled = JsonSchema.compile(Json.parse("{\"$ref\":\"" + SERVER.url("/cycle1.json") + "#\"}"), JsonSchema.Options.DEFAULT, options);
-        
-        // Validation should succeed by gracefully handling the cycle
-        var result = compiled.validate(Json.parse("\"test\""));
-        assertThat(result.valid()).isTrue();
+        // Cycles should be detected and throw an exception regardless of scheme
+        assertThatThrownBy(() -> JsonSchema.compile(
+            Json.parse("{\"$ref\":\"" + SERVER.url("/cycle1.json") + "#\"}"), 
+            JsonSchema.Options.DEFAULT, 
+            options
+        )).isInstanceOf(IllegalStateException.class)
+          .hasMessageContaining("ERROR: CYCLE: remote $ref cycle");
     }
 }