Throw StackOverflowError from initMethodStack; add StackOverflowError class and native test

[shai-almog]

Motivation

• Prevent an assertion crash when the VM call stack is exhausted by throwing a proper StackOverflowError so Java code can catch and recover.
• Provide the missing java.lang.StackOverflowError class so the VM can instantiate and throw the error.
• Add an integration test to validate that a stack overflow is thrown and that the VM can continue execution after it is caught.

Description

• Added vm/JavaAPI/src/java/lang/StackOverflowError.java implementing java.lang.VirtualMachineError.
• Updated vm/ByteCodeTranslator/src/nativeMethods.m to include the StackOverflowError header and change initMethodStack to check callStackOffset and call throwException(threadStateData, __NEW_INSTANCE_java_lang_StackOverflowError(threadStateData)) and return instead of asserting.
• Added vm/tests/src/test/java/com/codename1/tools/translator/StackOverflowIntegrationTest.java, a native integration test that compiles a small app which triggers a stack overflow, verifies the StackOverflowError was thrown/caught (STACK_OVERFLOW_OK) and that normal execution (a recursive sum) still works after recovery (RECOVERY_OK:7).

Testing

• No automated tests were executed as part of this change.
• A new automated integration test StackOverflowIntegrationTest was added under vm/tests and will run as part of the VM test suite when the test goals are invoked.
• The change is limited to VM native code, the JavaAPI, and an integration test; CI or a local Maven test run should be used to validate the new test in the full environment.

---

Codex Task

[github-actions]

✅ Continuous Quality Report

Test & Coverage

• ✅ Tests: 2283 total, 0 failed, 0 skipped
• 📊 Line coverage: 52.78% [HTML preview] [Download]
  • Lowest covered classes
    • com.codename1.io.rest.RequestBuilder$FetchAsPropertyListActionListener – 0.00%
    • com.codename1.io.rest.RequestBuilder$FetchAsPropertiesActionListener – 0.00%
    • com.codename1.ui.Display$EdtException – 0.00%
    • com.codename1.ui.BrowserWindow$BrowserForm – 0.00%
    • com.codename1.ui.plaf.CSSBorder$LinearGradient – 0.00%
    • com.codename1.io.rest.RequestBuilder$GetAsStringAsyncImplActionListener – 0.00%
    • com.codename1.io.rest.RequestBuilder$GetAsJsonMapActionListener – 0.00%
    • com.codename1.payment.Purchase$SynchronizeReceiptsSyncRunnable – 0.00%
    • com.codename1.io.rest.RequestBuilder$GetAsBytesAsyncImplActionListener – 0.00%
    • com.codename1.io.rest.RequestBuilder$FetchAsJsonMapActionListener – 0.00%

Static Analysis

• ✅ SpotBugs: 0 findings (no issues) [Report archive]
• ❌ PMD: 371 findings (P2: 42, P3: 319, P4: 10) [HTML preview] [Download]
  • Top findings
    • P2: CodenameOne/src/com/codename1/capture/Capture.java:252 – Use of modifier volatile is not recommended. (rule: AvoidUsingVolatile)
    • P2: CodenameOne/src/com/codename1/compat/java/util/Objects.java:47 – The method name and parameter number are suspiciously close to equals(Object) (rule: SuspiciousEqualsMethodName)
    • P2: CodenameOne/src/com/codename1/components/StorageImageAsync.java:43 – Use of modifier volatile is not recommended. (rule: AvoidUsingVolatile)
    • P2: CodenameOne/src/com/codename1/components/StorageImageAsync.java:44 – Use of modifier volatile is not recommended. (rule: AvoidUsingVolatile)
    • P2: CodenameOne/src/com/codename1/io/BufferedInputStream.java:38 – Use of modifier volatile is not recommended. (rule: AvoidUsingVolatile)
    • …and 366 more
• ❌ Checkstyle: 221026 findings (Warning: 221026) [HTML preview] [Download]
  • Top findings
    • Warning: CodenameOne/src/com/codename1/db/ThreadSafeDatabase.java:30:1 – Extra separation in import group before 'java.io.IOException' (rule: CustomImportOrderCheck)
    • Warning: CodenameOne/src/com/codename1/db/ThreadSafeDatabase.java:32 – First sentence of Javadoc is missing an ending period. (rule: SummaryJavadocCheck)
    • Warning: CodenameOne/src/com/codename1/db/ThreadSafeDatabase.java:36 – Line is longer than 100 characters (found 143). (rule: LineLengthCheck)
    • Warning: CodenameOne/src/com/codename1/db/ThreadSafeDatabase.java:39:5 – 'member def modifier' has incorrect indentation level 4, expected level should be 2. (rule: IndentationCheck)
    • Warning: CodenameOne/src/com/codename1/db/ThreadSafeDatabase.java:40:5 – 'member def modifier' has incorrect indentation level 4, expected level should be 2. (rule: IndentationCheck)
    • …and 221021 more

Generated automatically by the PR CI workflow.

[shai-almog]

iOS screenshot updates

Compared 30 screenshots: 23 matched, 6 updated, 1 missing reference.

• BrowserComponent — updated screenshot. Screenshot differs (1206x2622 px, bit depth 8).

  
  Preview info: Preview provided by instrumentation.
  Full-resolution PNG saved as BrowserComponent.png in workflow artifacts.

• graphics-draw-arc — updated screenshot. Screenshot differs (1206x2622 px, bit depth 8).

  
  Preview info: JPEG preview quality 20; JPEG preview quality 20; downscaled to 603x1311.
  Full-resolution PNG saved as graphics-draw-arc.png in workflow artifacts.

• graphics-draw-gradient — updated screenshot. Screenshot differs (1206x2622 px, bit depth 8).

  
  Preview info: JPEG preview quality 10; JPEG preview quality 10; downscaled to 844x1835.
  Full-resolution PNG saved as graphics-draw-gradient.png in workflow artifacts.

• graphics-draw-round-rect — missing reference. Reference screenshot missing at /Users/runner/work/CodenameOne/CodenameOne/scripts/ios/screenshots/graphics-draw-round-rect.png.

  
  Preview info: JPEG preview quality 10; JPEG preview quality 10; downscaled to 844x1835.
  Full-resolution PNG saved as graphics-draw-round-rect.png in workflow artifacts.

• graphics-draw-string — updated screenshot. Screenshot differs (1206x2622 px, bit depth 8).

  
  Preview info: JPEG preview quality 10; JPEG preview quality 10; downscaled to 422x918.
  Full-resolution PNG saved as graphics-draw-string.png in workflow artifacts.

• graphics-draw-string-decorated — updated screenshot. Screenshot differs (1206x2622 px, bit depth 8).

  
  Preview info: JPEG preview quality 10; JPEG preview quality 10; downscaled to 603x1311.
  Full-resolution PNG saved as graphics-draw-string-decorated.png in workflow artifacts.

• kotlin — updated screenshot. Screenshot differs (1206x2622 px, bit depth 8).

  
  Preview info: Preview provided by instrumentation.
  Full-resolution PNG saved as kotlin.png in workflow artifacts.

Benchmark Results

• VM Translation Time: 310 seconds
• Compilation Time: 159 seconds

Detailed Performance Metrics

Metric	Duration
Build Time Statistics
Setup & Unzip	27041 ms
Extract Extensions	14 ms
Google Services Setup	2 ms
Scan Classes	815 ms
Extract Libs	607 ms
Inject Build Hints	30 ms
Generate Unit Tests	2 ms
Generate Stubs	881 ms
Compile Stubs	2270 ms
Generate Icons	1094 ms
Prepare ParparVM	167 ms
ParparVM Execution	183289 ms
Post-VM Setup	94 ms
CocoaPods	4223 ms
Finalize	27 ms
Total Time	220557 msMaven Overhead : 90000 ms
CocoaPods Install (Script)	1000 ms
Simulator Boot	54000 ms
Simulator Boot (Run)	2000 ms
App Install	13000 ms
App Launch	7000 ms
Test Execution	135000 ms