feat: add support for private callable methods

[javier-godoy]

Summary by CodeRabbit

• New Features

  • Support invoking private legacy client-callable methods (primitives, wrappers, Elemental JSON types); discovery now aggregates callables across class hierarchies and detects incompatible overrides.
  • Improved handling of JsonValue-annotated parameters and return types to preserve legacy semantics.

• Tests

  • Added comprehensive test suite validating private callable invocation, JSON parameter/return handling, and cross-version compatibility.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[coderabbitai]

Walkthrough

Aggregates callable handler methods across class hierarchies, enables instrumentation of private @LegacyClientCallable methods via MethodHandle-based overrides (lookup helpers, static MethodHandle fields and clinit init), updates bytecode emission and JsonValue parameter handling, and adds many tests plus an abstract test harness for private callables.

Changes

Cohort / File(s)	Summary
Core instrumentation enhancement src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java	Renamed parameter, added getAllCallables, changed getInstrumentableMethods to use aggregated callables, added MethodHandle-based support for private methods (lookup helpers, private static MethodHandle fields, static clinit init), updated bytecode generation to invoke private targets via MethodHandle.invokeExact, and extended JsonValue parameter handling.
Private-parameter test fixtures src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java, src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java	Added multiple test classes extending BaseClientCallable with private test(...) methods annotated @LegacyClientCallable accepting various parameter types (primitives, String, elemental.json types) that call trace().
Private-return/typed test fixtures src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java, ...__I.java, ...__Integer.java, ...__JsonArray.java, ...__JsonBoolean.java, ...__JsonNull.java, ...__JsonNumber.java, ...__JsonObject.java, ...__JsonString.java, ...__JsonValue.java, ...__V.java, ...__Z.java	Added multiple test classes extending BaseClientCallable with private test() methods annotated @LegacyClientCallable returning various primitives, wrappers, and JSON types; methods call trace() and return appropriate values.
Subclass/inheritance test src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java	Added subclass that extends an existing private-callable fixture to validate inheritance and callable aggregation.
Abstract private-callable test framework src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java	Added abstract JUnit test base with reflective helpers to locate/invoke annotated private methods, abstract instrumentClass method, protected JSON factory hooks, and a suite of tests exercising private-callable fixtures and legacy comparisons.
Vaadin 24 concrete tests src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java	Concrete test subclass implementing instrumentClass via LegacyJsonMigrationHelper().instrumentClass(...) and elemental.json factory methods (Json.create*).
Vaadin 25 concrete tests src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java	Concrete test subclass implementing instrumentClass via JsonMigrationHelper25().instrumentClass(...) and Jackson node factory methods for JSON fixtures.

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~50 minutes

Areas needing extra attention:

• MethodHandle lookup helper generation and static clinit initialization in ClassInstrumentationUtil
• Bytecode emission paths: MethodHandle.invokeExact for private methods vs. INVOKESPECIAL for others
• Conflict detection in getAllCallables when same method name has differing parameter types across hierarchy
• Correct handling of JsonValue-annotated parameters and primitive boxing/unboxing in generated overrides
• Test harness alignment with instrumentClass behavior for Vaadin 24 vs 25 helpers

Possibly related PRs

• Add unit tests and fixes to class instrumentation #17 — Overlapping edits to callable discovery and instrumentation in ClassInstrumentationUtil.
• feat: add utility for class instrumentation AND feat: add JsonCodec encodeWithoutTypeInfo #16 — Prior changes to ClassInstrumentationUtil that this PR extends with private-method handling and MethodHandle support.

Suggested reviewers

• mlopezFC
• paodb

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 2.41% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'feat: add support for private callable methods' accurately describes the main change: enabling private methods to be invoked via the instrumentation framework, which is evidenced by 26 new test classes and significant enhancements to ClassInstrumentationUtil.java for handling private method invocation.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch private-callables

---

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[coderabbitai]

Actionable comments posted: 7

🧹 Nitpick comments (4)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java (1)

6-12: JsonNumber fixture looks good; double‑check visibility vs. “Private” naming

The test setup (trace + Json.create(0) as JsonNumber) is correct and aligned with the other LegacyClientCallable fixtures.

One thing to confirm: the class is named LegacyClientCallablePrivate__JsonNumber, but the annotated test method is public. If other LegacyClientCallablePrivate__* fixtures use private methods to exercise the new private‑callable support, you might want to make this method private as well for consistency, unless this one is intentionally public for a specific scenario.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java (1)

4-13: Consider adding a conditional test skip mechanism.

The comment on line 12 indicates this test requires Vaadin 25 on the classpath and won't work otherwise. Consider using JUnit's @Ignore with a clear reason, or an Assume.assumeTrue() check to gracefully skip when Vaadin 25 is not available:

+import org.junit.Assume;
+import org.junit.Before;
...
 // this test doesn't work as-in because it requires Vaadin 25 in the classpath
 public class LegacyClientCallablesPrivateTest25 extends LegacyClientCallablesPrivateTest {
+
+  @Before
+  public void checkVaadin25Available() {
+    try {
+      Class.forName("tools.jackson.databind.node.NullNode");
+    } catch (ClassNotFoundException e) {
+      Assume.assumeTrue("Vaadin 25 not available", false);
+    }
+  }

Also, the tools.jackson.databind package path appears to be Vaadin 25's repackaged Jackson. Please verify this is the correct package for your target Vaadin 25 version.

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (1)

359-364: Minor: Fix typo in comment.

The comment says "unresolve" but the method being invoked is unreflect.

-      // Invoke Lookup.unresolve(method)
+      // Invoke Lookup.unreflect(method)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1)

42-43: Consider using assertNotNull for clearer intent.

-    assertTrue(MESSAGE, testMethod != null);
+    assertNotNull(MESSAGE, testMethod);

This more clearly expresses the assertion intent.

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 17c0dfd and 0937288.

📒 Files selected for processing (28)

• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (8 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Integer.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Z.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java (1 hunks)

🧰 Additional context used

🧠 Learnings (1)

📚 Learning: 2025-11-25T16:35:42.544Z

Learnt from: javier-godoy
Repo: FlowingCode/JsonMigrationHelper PR: 11
File: src/main/java/com/flowingcode/vaadin/jsonmigration/JsonSerializer.java:281-301
Timestamp: 2025-11-25T16:35:42.544Z
Learning: In the JsonMigrationHelper project, code copied from the Vaadin codebase should be kept consistent with the original source unless there's a specific reason to deviate.

Applied to files:

• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java
• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java

🔇 Additional comments (25)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java (1)

5-11: LGTM!

The test fixture correctly implements a private method with @LegacyClientCallable annotation, consistent with the class naming convention for testing private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java (1)

5-11: LGTM!

The test fixture correctly implements a private method with @LegacyClientCallable annotation for JsonBoolean parameter type testing.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java (1)

3-9: LGTM!

The test fixture correctly implements a private method with @LegacyClientCallable annotation for String parameter type testing.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java (1)

1-9: LGTM!

This test fixture correctly defines a private method with a boolean parameter annotated with @LegacyClientCallable. The implementation follows the expected pattern for testing private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java (1)

1-5: LGTM!

This empty extension class serves as a test fixture to verify that private callable instrumentation works correctly with inheritance hierarchies.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java (1)

1-13: LGTM!

The test fixture correctly returns a JsonString value. Note that while the class name includes "Private", this method is public, which aligns with the test suite's goal of validating that instrumentation doesn't break existing public callables alongside the new private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java (1)

1-11: LGTM!

This test fixture correctly defines a private method with a JsonArray parameter. The implementation follows the expected pattern for testing private callable support with JSON types.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java (1)

1-9: LGTM!

This test fixture correctly defines a private method with a double parameter. The implementation follows the expected pattern for testing private callable support with primitive types.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java (1)

1-13: LGTM!

The test fixture correctly returns a JsonObject value. Consistent with the test suite pattern, this public method verifies that instrumentation maintains compatibility with existing public callables.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java (1)

1-11: LGTM!

This test fixture correctly defines a private method with a JsonObject parameter. The implementation follows the expected pattern for testing private callable support with JSON types.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java (1)

1-10: LGTM!

The test fixture correctly returns an int value. This public method fixture ensures that instrumentation maintains compatibility with existing public callables alongside the new private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java (1)

3-8: Private void fixture looks correct

LegacyClientCallablePrivate__V correctly defines a private, no-arg, void @LegacyClientCallable that just calls trace(), matching the intended private-callable test pattern.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java (1)

3-10: Private JsonNull-arg fixture is consistent

LegacyClientCallablePrivate_JsonNull__V defines a private @LegacyClientCallable with a JsonNull parameter and void return, which matches the private-parameter coverage pattern for these tests.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java (1)

3-8: Int-arg private void fixture is correct

LegacyClientCallablePrivate_I__V properly declares a private @LegacyClientCallable with an int parameter and void return, which aligns with the private-callable coverage pattern.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java (1)

3-10: JsonString-arg private fixture matches pattern

LegacyClientCallablePrivate_JsonString__V correctly defines a private @LegacyClientCallable taking a JsonString and returning void, consistent with the rest of the private-parameter fixtures.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java (1)

6-12: Method visibility may not match class naming convention.

The class name LegacyClientCallablePrivate__JsonValue suggests this is a test fixture for private callables, but the test() method is declared as public. Other fixtures in this PR (e.g., LegacyClientCallablePrivate_JsonNumber__V) declare their methods as private. Please verify whether this should be private for consistency with the naming pattern, or if the public visibility is intentional.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java (1)

5-11: LGTM!

The test fixture correctly implements a private method annotated with @LegacyClientCallable, with proper naming convention and trace verification pattern.

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (4)

167-185: LGTM!

The getAllCallables method correctly aggregates callable methods from the class hierarchy, detects conflicts when methods share a name but have different parameter types, and ensures subclass methods take precedence. The error message is clear and actionable.

---

280-311: LGTM!

The implementation correctly generates static fields for MethodHandles and initializes them in <clinit>. The field naming by method name is safe because getAllCallables prevents same-name methods with different parameter types.

---

474-482: LGTM!

The pushInt helper correctly handles the various int constant opcodes: ICONST_* for -1 to 5, BIPUSH for byte range, and SIPUSH for short range.

---

484-508: LGTM!

The loadClassConstant helper correctly handles all primitive types by loading the corresponding TYPE field from wrapper classes, and uses Type.getType() for reference types.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (2)

60-67: LGTM!

The testExtends__V test properly validates that instrumentation works for subclasses of private callable fixtures.

---

109-127: No changes needed. The fixture classes declare test() as public, not private. The "Private" in class names (LegacyClientCallablePrivate__Z, etc.) refers to the callable's metadata designation, not the Java access modifier. Direct calls like nonInstrumented.test() on lines 116 and 126 are valid and will compile correctly.

Likely an incorrect or invalid review comment.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (2)

6-11: LGTM!

The class correctly extends the base test class and overrides instrumentClass to use LegacyJsonMigrationHelper, which is appropriate for Vaadin 24 testing. Creating a new helper instance per call ensures test isolation.

---

13-41: No issues identified. The JSON factory methods correctly use elemental.json.Json for Vaadin 14, which is the project's target version as specified in pom.xml. The "Test24" suffix refers to a test case variant, not Vaadin 24. The JsonMigrationHelper is explicitly designed to handle legacy elemental.json APIs, making these methods appropriate for this codebase.

[coderabbitai]

Actionable comments posted: 2

♻️ Duplicate comments (1)

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (1)

421-430: Use invoke() instead of invokeExact for MethodHandle invocation of private methods.

The invokeExact call requires exact type matching. Since the instrumented class is a subclass of method.getDeclaringClass(), the receiver (this) will be a subtype, causing WrongMethodTypeException at runtime. Replace invokeExact with invoke, which allows subtype compatibility.

Apply this diff:

       if (isPrivate) {
         // Call private method
         String descriptor =
             "(" + Type.getDescriptor(method.getDeclaringClass())
             + superDescriptor.substring(1);
         mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
             "java/lang/invoke/MethodHandle",
-            "invokeExact",
+            "invoke",
             descriptor,
             false);

🧹 Nitpick comments (1)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1)

43-44: Consider using assertNotNull for null checks.

assertNotNull(MESSAGE, testMethod) is more idiomatic and provides clearer failure diagnostics than assertTrue(MESSAGE, testMethod != null).

- assertTrue(MESSAGE, testMethod != null);
+ assertNotNull(MESSAGE, testMethod);

Also add the import:

import static org.junit.Assert.assertNotNull;

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 0937288 and b5a58b4.

📒 Files selected for processing (28)

• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (8 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Integer.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Z.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java (1 hunks)

✅ Files skipped from review due to trivial changes (1)

• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java

🚧 Files skipped from review as they are similar to previous changes (15)

• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Z.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java

🧰 Additional context used

🧠 Learnings (1)

📚 Learning: 2025-11-25T16:35:42.544Z

Learnt from: javier-godoy
Repo: FlowingCode/JsonMigrationHelper PR: 11
File: src/main/java/com/flowingcode/vaadin/jsonmigration/JsonSerializer.java:281-301
Timestamp: 2025-11-25T16:35:42.544Z
Learning: In the JsonMigrationHelper project, code copied from the Vaadin codebase should be kept consistent with the original source unless there's a specific reason to deviate.

Applied to files:

• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java
• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java

🔇 Additional comments (17)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java (1)

1-12: Private JsonNull callable fixture looks correct

Class name, private visibility of test(), @LegacyClientCallable usage, trace() call, and returning Json.createNull() are all consistent and appropriate for this private-callable fixture.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java (1)

1-11: LGTM! Test fixture is well-structured.

The test class correctly validates private method instrumentation for @LegacyClientCallable with a JsonValue parameter. The unused parameter is expected in this context—the test verifies that the instrumentation framework can invoke the private method with the correct parameter type, with trace() confirming successful invocation.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java (1)

8-12: LGTM! Method visibility corrected to private.

The method is now correctly declared as private, matching the fixture naming convention and ensuring the private-method callable path is exercised.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java (1)

8-12: LGTM! Private method correctly implements test fixture.

The private method declaration and JsonValue return type correctly exercise the private callable instrumentation path.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java (1)

8-12: LGTM! Private method correctly implements test fixture.

The private method declaration correctly matches the fixture intent and will exercise the private callable path.

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (4)

155-165: LGTM! Correctly updated to include private methods.

The parameter rename and filter adjustment correctly enable private methods to be considered as callable candidates.

---

280-311: LGTM! Well-designed MethodHandle caching mechanism.

The static field initialization and <clinit> generation correctly implement a caching strategy for private method MethodHandles, avoiding repeated reflection overhead.

---

313-371: LGTM! Correct bytecode generation for MethodHandle lookup.

The createLookupHelper method correctly generates bytecode that:

1. Obtains a MethodHandles.Lookup instance
2. Reflectively retrieves the private method
3. Makes it accessible
4. Unreflects it to obtain a MethodHandle

The implementation properly handles primitive and object parameter types.

---

474-508: LGTM! Correct bytecode helper utilities.

Both pushInt and loadClassConstant correctly generate appropriate bytecode instructions for their respective purposes, properly handling primitives and objects.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java (1)

8-12: LGTM! Method visibility corrected to private.

The method is now correctly declared as private, matching the fixture naming convention and ensuring the private-method callable path is properly tested.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java (1)

5-8: LGTM! Private void-return test fixture correctly implemented.

The private method declaration properly exercises the void-return private callable path.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java (1)

5-8: LGTM! Private method with String parameter correctly implemented.

The private method declaration properly tests the String parameter handling in the private callable instrumentation path.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Integer.java (1)

5-9: LGTM! Method visibility corrected to private.

The method is now correctly declared as private, consistent with the fixture naming convention and other similar test classes.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java (1)

1-10: LGTM!

Test fixture follows the established pattern for private callable method testing. The naming convention __I correctly indicates the return type (int), and the implementation properly calls trace() for verification.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (3)

1-14: LGTM!

Clean import structure and well-designed abstract method with bounded type parameter for type safety.

---

56-66: LGTM!

Using Object as the return type provides flexibility for concrete implementations to return version-specific JSON types (e.g., elemental.json vs jakarta.json).

---

68-281: LGTM!

Comprehensive test coverage for various parameter and return type combinations including primitives, wrappers, and JSON types. The inheritance test (testExtends__V) is a valuable addition for verifying that instrumentation works correctly with class hierarchies.

[coderabbitai]

Actionable comments posted: 0

♻️ Duplicate comments (2)

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (1)

420-429: Use invoke() instead of invokeExact for private method invocation.

This issue was flagged in a previous review. The invokeExact call requires exact type matching, but the receiver (this loaded at line 395) is an instance of the instrumented subclass, while the descriptor expects the declaring class. This will cause WrongMethodTypeException at runtime.

Apply this diff:

       if (isPrivate) {
         // Call private method
         String descriptor =
             "(" + Type.getDescriptor(method.getDeclaringClass())
             + superDescriptor.substring(1);
         mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
             "java/lang/invoke/MethodHandle",
-            "invokeExact",
+            "invoke",
             descriptor,
             false);
       }

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1)

49-53: Add null check for testMethod to avoid NPE.

Unlike invokeTestMethod, this method doesn't verify that the method was found before calling setAccessible. If no method with @LegacyClientCallable exists, testMethod will be null and line 51 will throw NullPointerException.

Apply this diff:

  private static Object invokeLegacyMethod(BaseClientCallable instrumented, Object... args) throws Exception {
    Method testMethod = getAnnotatedTestMethod(instrumented, LegacyClientCallable.class);
+   assertTrue("instrumented method is not annotated with @LegacyClientCallable", testMethod != null);
    testMethod.setAccessible(true);
    return testMethod.invoke(instrumented, args);
  }

🧹 Nitpick comments (1)

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (1)

312-370: Consider adding exception handling for robust initialization.

The lookup_* helper methods perform reflection operations that can throw checked exceptions (NoSuchMethodException, SecurityException, IllegalAccessException). Since these are invoked in <clinit>, any exception wraps in ExceptionInInitializerError, which is difficult to diagnose.

Consider wrapping the reflection calls in a try-catch that re-throws as a more descriptive RuntimeException:

// In the generated bytecode, wrap in try-catch
// and throw RuntimeException with context about which method failed

Alternatively, document that initialization failures are intentional fail-fast behavior.

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between b5a58b4 and 067186b.

📒 Files selected for processing (28)

• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (8 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Integer.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Z.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (14)

• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Integer.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java

🧰 Additional context used

🧠 Learnings (1)

📚 Learning: 2025-11-25T16:35:42.544Z

Learnt from: javier-godoy
Repo: FlowingCode/JsonMigrationHelper PR: 11
File: src/main/java/com/flowingcode/vaadin/jsonmigration/JsonSerializer.java:281-301
Timestamp: 2025-11-25T16:35:42.544Z
Learning: In the JsonMigrationHelper project, code copied from the Vaadin codebase should be kept consistent with the original source unless there's a specific reason to deviate.

Applied to files:

• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java
• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java

🔇 Additional comments (17)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java (1)

1-11: Private JsonArray callable test helper looks correct

The class wiring, annotation usage, visibility (private method), and JsonArray import all look consistent with the described pattern for other LegacyClientCallablePrivate_*__V test classes. No changes requested.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java (2)

1-3: LGTM!

Package declaration and import are appropriate for this test fixture.

---

5-10: LGTM!

This test fixture correctly demonstrates a private method annotated with @LegacyClientCallable accepting a JsonNumber parameter. The implementation is appropriate for testing the MethodHandle-based instrumentation of private methods.

The arg parameter is unused within the method body, which is acceptable for a test fixture focused on verifying invocation mechanics rather than parameter handling.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java (1)

1-11: JsonObject private void fixture looks correct

Class cleanly exercises a private @LegacyClientCallable with JsonObject parameter and void return via trace(). No changes needed.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java (1)

1-11: JsonBoolean private void fixture is consistent and valid

Private @LegacyClientCallable with JsonBoolean argument correctly mirrors the other void-return variants and uses trace() for verification.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java (1)

1-13: JsonNumber private-return fixture is correct

This class neatly covers the private JsonNumber-return scenario (Json.create(0)), aligning with the rest of the private callable matrix.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java (1)

1-13: JsonNull private-return fixture matches private-callable intent

test() is private, annotated, and returns Json.createNull(), so the fixture now correctly exercises the private JsonNull-return path.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java (1)

1-10: Double-return private fixture is consistent

Private test() with double return and trace() matches the pattern for primitive private-callable fixtures.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java (1)

1-9: Int-parameter private void fixture is fine

This provides the private int-parameter, void-return case and aligns with other *_I__V-style tests.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Z.java (1)

1-10: Boolean-return private fixture correctly configured

test() is private, annotated, and returns a constant boolean after trace(), matching the private-callable boolean coverage goal.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java (1)

1-10: Int-return private fixture looks good

Private @LegacyClientCallable returning int via a simple constant plus trace() is aligned with the rest of the primitive fixtures.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java (1)

6-12: LGTM!

The test fixture correctly implements a private @LegacyClientCallable method, matching the fixture naming convention. The implementation is straightforward and aligns with the PR's goal of supporting private callable methods.

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (3)

167-184: LGTM - Method overriding logic correctly preserves subclass methods.

The logic now properly:

1. Adds the method if no existing entry (subclass version seen first)
2. Throws if same name but different parameter types (conflict)
3. Silently skips if same name and parameters (keeps subclass version)

This correctly implements the expected override semantics when iterating from subclass to superclass.

---

473-507: LGTM!

The bytecode utility methods are correctly implemented:

• pushInt properly selects between ICONST_*, BIPUSH, and SIPUSH based on value range
• loadClassConstant correctly handles all 8 primitive types via wrapper TYPE fields and reference types via LDC

---

279-310: LGTM - Static initialization pattern for MethodHandle fields.

The generated <clinit> correctly:

1. Iterates private method names
2. Invokes each lookup_* helper to obtain the MethodHandle
3. Stores the result in the corresponding static field

This ensures MethodHandles are initialized once at class load time.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1)

67-280: LGTM - Comprehensive test coverage.

The test suite thoroughly covers:

• Void return types with various parameter types (primitives, String, JsonValue subtypes)
• Primitive and wrapper return types (boolean, int, double, Integer)
• All JsonValue subtypes (JsonBoolean, JsonNumber, JsonString, JsonNull, JsonArray, JsonObject)
• Inheritance scenario (ExtendsLegacyClientCallablePrivate__V)

Each test properly verifies that the method was traced and compares results against non-instrumented instances.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (1)

6-43: LGTM!

Clean implementation of the abstract test base:

• Correctly delegates instrumentClass to LegacyJsonMigrationHelper
• All JSON factory methods properly use elemental.json.Json to create appropriate values

[coderabbitai]

Actionable comments posted: 0

♻️ Duplicate comments (1)

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (1)

411-420: Use invoke() instead of invokeExact for MethodHandle invocation of private methods.

This issue was previously flagged but appears unresolved. The invokeExact call requires exact type matching, but this is a subclass of method.getDeclaringClass(), which will cause WrongMethodTypeException at runtime.

       mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
           "java/lang/invoke/MethodHandle",
-          "invokeExact",
+          "invoke",
           descriptor,
           false);

Note: invoke returns Object and throws Throwable, so adjust the descriptor accordingly:

-      String descriptor =
-          "(" + Type.getDescriptor(method.getDeclaringClass())
-          + superDescriptor.substring(1);
+      String descriptor = "(" + Type.getDescriptor(Object.class);
+      for (Class<?> pt : method.getParameterTypes()) {
+        descriptor += Type.getDescriptor(Object.class);
+      }
+      descriptor += ")Ljava/lang/Object;";

Then cast/unbox the result as needed based on the return type.

🧹 Nitpick comments (1)

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (1)

315-315: Consider simplifying class constant loading.

The current approach is functionally correct but verbose. You can simplify:

-      mv.visitLdcInsn(Type.getObjectType(Type.getInternalName(method.getDeclaringClass())));
+      mv.visitLdcInsn(Type.getType(method.getDeclaringClass()));

Both produce the same bytecode, but Type.getType(Class) is more direct.

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 067186b and ba81018.

📒 Files selected for processing (1)

• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (9 hunks)

🧰 Additional context used

🧠 Learnings (1)

📚 Learning: 2025-11-25T16:35:42.544Z

Learnt from: javier-godoy
Repo: FlowingCode/JsonMigrationHelper PR: 11
File: src/main/java/com/flowingcode/vaadin/jsonmigration/JsonSerializer.java:281-301
Timestamp: 2025-11-25T16:35:42.544Z
Learning: In the JsonMigrationHelper project, code copied from the Vaadin codebase should be kept consistent with the original source unless there's a specific reason to deviate.

Applied to files:

• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java

🔇 Additional comments (5)

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (5)

155-165: LGTM!

The filter correctly includes private methods by only checking for non-static modifiers, enabling the new private callable instrumentation feature.

---

167-184: LGTM!

The method correctly aggregates callable methods across the class hierarchy, preserving the subclass version when overrides exist and properly detecting conflicts when parameter types differ.

---

186-207: LGTM!

The method correctly uses getAllCallables to gather methods from the entire hierarchy, and the filtering logic properly distinguishes between legacy and current Vaadin behavior.

---

270-301: LGTM!

The static field generation and class initializer correctly set up MethodHandle references for private methods. The approach of using method names as field names is safe since getAllCallables already prevents duplicate method names.

---

464-498: LGTM!

The pushInt helper correctly selects optimal opcodes based on value range. The loadClassConstant helper properly handles all primitive types via wrapper class TYPE fields and uses Type.getType for object types.

[coderabbitai]

Actionable comments posted: 0

♻️ Duplicate comments (1)

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (1)

411-420: Use invoke() instead of invokeExact for MethodHandle invocation of private methods.

The invokeExact call requires exact type matching. Since the instrumented class is a subclass of method.getDeclaringClass(), the receiver (this) will be a subtype, causing WrongMethodTypeException at runtime. Replace invokeExact with invoke, which allows subtype compatibility.

Apply this diff:

       if (isPrivate) {
         // Call private method
         String descriptor =
             "(" + Type.getDescriptor(method.getDeclaringClass())
             + superDescriptor.substring(1);
         mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
             "java/lang/invoke/MethodHandle",
-            "invokeExact",
+            "invoke",
             descriptor,
             false);

🧹 Nitpick comments (1)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (1)

6-11: instrumentClass override looks correct; consider reusing the helper if desired

The generic signature and delegation to LegacyJsonMigrationHelper().instrumentClass(clazz) look correct and type-safe for test purposes.
If this pattern is used heavily across tests and you care about a tiny allocation reduction, you could keep a single LegacyJsonMigrationHelper instance as a field and reuse it, but it’s not required here.

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between ba81018 and b8ebbcf.

📒 Files selected for processing (28)

• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (9 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Integer.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Z.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (1 hunks)
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (19)

• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNumber.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Z.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_String__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonArray__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest25.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__I.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonObject__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonNull.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/ExtendsLegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNull__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__Integer.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_D__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonString.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonValue__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonValue.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonArray.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonString__V.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonBoolean__V.java

🧰 Additional context used

🧠 Learnings (1)

📚 Learning: 2025-11-25T16:35:42.544Z

Learnt from: javier-godoy
Repo: FlowingCode/JsonMigrationHelper PR: 11
File: src/main/java/com/flowingcode/vaadin/jsonmigration/JsonSerializer.java:281-301
Timestamp: 2025-11-25T16:35:42.544Z
Learning: In the JsonMigrationHelper project, code copied from the Vaadin codebase should be kept consistent with the original source unless there's a specific reason to deviate.

Applied to files:

• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java
• src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java
• src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java

🔇 Additional comments (16)

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_JsonNumber__V.java (1)

1-11: LGTM!

This test fixture correctly implements a private @LegacyClientCallable method with a JsonNumber parameter, following the pattern established for testing private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonObject.java (1)

1-13: LGTM!

This test fixture correctly implements a private @LegacyClientCallable method returning JsonObject, following the pattern established for testing private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_Z__V.java (1)

1-9: LGTM!

This test fixture correctly implements a private @LegacyClientCallable method with a boolean parameter, following the pattern established for testing private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__D.java (1)

1-10: LGTM!

This test fixture correctly implements a private @LegacyClientCallable method returning double, following the pattern established for testing private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate_I__V.java (1)

1-9: LGTM!

This test fixture correctly implements a private @LegacyClientCallable method with an int parameter, following the pattern established for testing private callable support.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablePrivate__JsonBoolean.java (1)

1-13: LGTM!

This test fixture correctly implements a private @LegacyClientCallable method returning JsonBoolean, following the pattern established for testing private callable support.

src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java (8)

31-33: LGTM!

The new imports support the enhanced method aggregation logic in getAllCallables.

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155-165: LGTM!

The filter change from !Modifier.isPrivate to !Modifier.isStatic correctly enables private @LegacyClientCallable methods to be processed, which is the core goal of this PR.

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167-184: LGTM!

The getAllCallables method correctly aggregates handler methods across the class hierarchy while preserving subclass overrides and detecting conflicts where the same method name has different parameter types.

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270-301: LGTM!

The infrastructure for handling private methods is well-designed: collecting private method names, generating static MethodHandle fields, creating lookup helpers, and initializing handles in <clinit>.

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303-361: LGTM!

The createLookupHelper method correctly generates bytecode to obtain a MethodHandle for private methods via MethodHandles.lookup().unreflect(), with proper setAccessible(true) handling.

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377-383: LGTM!

Loading the MethodHandle from the static field for private methods is the correct approach for preparing the invocation.

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464-498: LGTM!

The utility methods pushInt and loadClassConstant are well-implemented. pushInt uses the most efficient bytecode for each value range, and loadClassConstant correctly handles primitive types by loading their TYPE fields from wrapper classes.

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389-409: LGTM!

The parameter conversion logic correctly handles JsonValue-annotated parameters with proper type conversion and casting, while preserving the existing behavior for non-JsonValue parameters.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest.java (1)

1-282: LGTM!

This abstract test base provides comprehensive coverage for private callable methods across various parameter and return types. The reflection-based helper methods cleanly abstract the invocation details, and the abstract fixture methods enable version-specific implementations.

src/test/java/com/flowingcode/vaadin/jsonmigration/LegacyClientCallablesPrivateTest24.java (1)

13-41: JSON creator overrides are consistent and suitable for the tests

All JSON factory overrides correctly use Json.create* and return values as Object, which matches the likely abstract contract in the base test. The chosen literals (true, 42, "test") are fine as stable sample values for assertions.