Add Executor framework support to JavaAPI

[google-labs-jules]

Implemented java.util.concurrent Executor framework from scratch to replace potential copyrighted code and ensure compatibility with the minimal ParparVM test harness.

Key changes:

• Created clean-room implementations for Executor, ExecutorService, Future, Callable, Executors, FutureTask, LinkedBlockingQueue, AtomicInteger, and related exceptions in vm/JavaAPI.
• Implemented SimpleThreadPool using standard Java synchronization (wait/notify) to avoid dependency on ReentrantLock and Unsafe.
• Added ExecutorIntegrationTest in vm/tests which compiles a test application using the new framework, translates it to C, and verifies execution.
• Updated CompilerHelper in vm/tests with necessary native stubs to support linking the new concurrent classes.
• Verified compilation and basic execution logic.

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PR created automatically by Jules for task 25243132648091636 started by @shai-almog

[google-labs-jules]

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[github-actions]

✅ Continuous Quality Report

Test & Coverage

• ✅ Tests: 2280 total, 0 failed, 0 skipped
• 📊 Line coverage: 52.90% [HTML preview] [Download]
  • Lowest covered classes
    • com.codename1.ui.BrowserWindow$BrowserForm – 0.00%
    • com.codename1.processing.TextEvaluator – 3.85%
    • com.codename1.charts.views.PieChart – 4.00%
    • com.codename1.charts.views.PieMapper – 4.88%
    • com.codename1.charts.views.ScatterChart – 5.32%
    • com.codename1.ui.list.GenericListCellRenderer$Monitor – 5.33%
    • com.codename1.ui.Display$EdtException – 5.56%
    • com.codename1.testing.AbstractTest – 6.05%
    • com.codename1.ui.Transform$ImmutableTransform – 6.06%
    • com.codename1.charts.views.DoughnutChart – 6.25%

Static Analysis

• ❌ SpotBugs: 688 findings (High: 56, Normal: 423, Low: 209) [HTML preview] [Download]
  • Top findings
    • High: CodenameOne/src/com/codename1/charts/views/XYChart.java:128 – Call to equals() comparing different types (rule: EC_UNRELATED_TYPES)
    • High: CodenameOne/src/com/codename1/components/ImageViewer.java:310 – Condition has no effect (rule: UC_USELESS_CONDITION)
    • High: CodenameOne/src/com/codename1/components/ToastBar.java:1021 – Potentially ambiguous invocation of either an inherited or outer method (rule: IA_AMBIGUOUS_INVOCATION_OF_INHERITED_OR_OUTER_METHOD)
    • High: CodenameOne/src/com/codename1/facebook/FaceBookAccess.java:191 – Reliance on default encoding (rule: DM_DEFAULT_ENCODING)
    • High: CodenameOne/src/com/codename1/io/BufferedInputStream.java:441 – Reliance on default encoding (rule: DM_DEFAULT_ENCODING)
    • …and 683 more
• ❌ PMD: 2711 findings (P2: 1, P3: 634, P4: 2076) [HTML preview] [Download]
  • Top findings
    • P2: CodenameOne/src/com/codename1/ui/Display.java:1022 – Avoid using a branching statement as the last in a loop. (rule: AvoidBranchingStatementAsLastInLoop)
    • P3: CodenameOne/src/com/codename1/charts/views/LineChart.java:208 – These nested if statements could be combined (rule: CollapsibleIfStatements)
    • P3: CodenameOne/src/com/codename1/facebook/FacebookRESTService.java:76 – Avoid unused constructor parameters such as 'token'. (rule: UnusedFormalParameter)
    • P3: CodenameOne/src/com/codename1/impl/CodenameOneImplementation.java:8454 – These nested if statements could be combined (rule: CollapsibleIfStatements)
    • P3: CodenameOne/src/com/codename1/impl/FullScreenAdService.java:103 – These nested if statements could be combined (rule: CollapsibleIfStatements)
    • …and 2706 more
• ❌ Checkstyle: 220023 findings (Warning: 220023) [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 220018 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: 352 seconds
• Compilation Time: 92 seconds

Detailed Performance Metrics

Metric	Duration
Build Time Statistics
Setup & Unzip	35783 ms
Extract Extensions	25 ms
Google Services Setup	2 ms
Scan Classes	1686 ms
Extract Libs	830 ms
Inject Build Hints	59 ms
Generate Unit Tests	3 ms
Generate Stubs	1320 ms
Compile Stubs	2912 ms
Generate Icons	2597 ms
Prepare ParparVM	292 ms
ParparVM Execution	183541 ms
Post-VM Setup	135 ms
CocoaPods	4353 ms
Finalize	39 ms
Total Time	233578 msMaven Overhead : 119000 ms
CocoaPods Install (Script)	2000 ms
Simulator Boot (Run)	66000 ms
App Install	12000 ms
App Launch	5000 ms
Test Execution	167000 ms

[github-actions]

✅ ByteCodeTranslator Quality Report

Test & Coverage

• ✅ Tests: 169 total, 0 failed, 2 skipped

Benchmark Results

• Execution Time: 9766 ms

• Hotspots (Top 20 sampled methods):

  • 23.70% java.lang.String.indexOf (405 samples)
  • 17.50% com.codename1.tools.translator.Parser.isMethodUsed (299 samples)
  • 15.21% com.codename1.tools.translator.Parser.addToConstantPool (260 samples)
  • 9.30% java.util.ArrayList.indexOf (159 samples)
  • 3.86% java.lang.Object.hashCode (66 samples)
  • 3.34% com.codename1.tools.translator.ByteCodeClass.calcUsedByNative (57 samples)
  • 2.69% java.lang.System.identityHashCode (46 samples)
  • 2.11% com.codename1.tools.translator.ByteCodeClass.fillVirtualMethodTable (36 samples)
  • 1.76% com.codename1.tools.translator.BytecodeMethod.equals (30 samples)
  • 1.40% com.codename1.tools.translator.BytecodeMethod.optimize (24 samples)
  • 1.35% java.lang.Integer.getChars (23 samples)
  • 1.23% com.codename1.tools.translator.Parser.cullMethods (21 samples)
  • 1.23% java.io.FileOutputStream.writeBytes (21 samples)
  • 1.23% java.lang.StringBuilder.append (21 samples)
  • 1.11% com.codename1.tools.translator.ByteCodeClass.markDependent (19 samples)
  • 0.94% java.io.FileOutputStream.open0 (16 samples)
  • 0.59% java.io.FileInputStream.open0 (10 samples)
  • 0.59% com.codename1.tools.translator.Parser.generateClassAndMethodIndexHeader (10 samples)
  • 0.53% com.codename1.tools.translator.BytecodeMethod.appendCMethodPrefix (9 samples)
  • 0.53% java.lang.StringCoding$StringEncoder.encode (9 samples)

• ⚠️ Coverage report not generated.

Static Analysis

• ✅ SpotBugs: no findings (report was not generated by the build).
• ⚠️ PMD report not generated.
• ⚠️ Checkstyle report not generated.

Generated automatically by the PR CI workflow.