Support Native Image for Edge

[tnikolai2]

Lambda expressions are replaced by classes because GraalVM Native Image does not support the use of lambda expressions in jni callback functions.

Also need add to jni-config.json:

[
  {
    "name": "org.eclipse.swt.browser.Edge$HandleCoreWebView2SwtCallback",
    "methods": [
      {
        "name": "Invoke",
        "parameterTypes": ["long", "long"]
      }
    ]
  },
  {
    "name": "org.eclipse.swt.browser.Edge$HandleCoreWebView2SwtHost",
    "methods": [
      {
        "name": "CallJava",
        "parameterTypes": ["int", "long", "long"]
      }
    ]
  }
]

[github-actions]

Test Results

   545 files  ±0     545 suites  ±0   29m 35s ⏱️ + 1m 55s
 4 400 tests ±0   4 382 ✅ ±0   18 💤 ±0  0 ❌ ±0 
16 727 runs  ±0  16 587 ✅ ±0  140 💤 ±0  0 ❌ ±0 

Results for commit 64562d5. ± Comparison against base commit 18eaec6.

♻️ This comment has been updated with latest results.

[HeikoKlare]

Thank you for the contribution! This looks like a proper refactoring to me and if that helps to use Edge with GraalVM, that's of course fine.

@tnikolai2 can please properly format the lines of code that you have touched? In particular, the added lines use whitespaces for indentation while the surrounding code uses tabs. And it would be great if you could use a more expressive headline in your commit than "Update Edge.java".

You also refer to the necessity to add a jni-config.json. Is that something that needs to be done locally in an application executed on GraalVM? In that case, it might make sense that we add this specific knowledge about usage with GraalVM to the FAQ: https://github.com/eclipse-platform/eclipse.platform/blob/master/docs/FAQ/FAQ_How_do_I_use_Edge-IE_as_the_Browser's_underlying_renderer.md

[tnikolai2]

I fix whitespaces.

---

If complile with GraalVM with mvn -Pnative package
will be many problems with java.lang.ClassNotFoundException. And this problem is not limited to the browser.

To fix java.lang.ClassNotFoundException, need provide reachability metadata files (e.g. reachability-metadata.json or legacy jni-config.json)
It must be placed under META-INF/native-image/<groupId>/<artifactId>/
This can be done either in the user project or inside a library, or both.

These metadata files can be auto-generated by running the application with the native image agent:
java -agentlib:native-image-agent=config-output-dir=./native-config -jar sample.jar

However, due to limitations in GraalVM, inline lambdas cannot be referenced in reachability metadata.
To address this, I replaced lambdas with separate inner classes.

But compiling with GraalVM and creating reachability metadata it is a big separate task.

[tnikolai2]

Here is an example for Windows:
SequrFlySWT1.zip

target/SequrFly-1.0-SNAPSHOT-jar-with-dependencies.jar - full jar with updated Edge.java or can generate with mvn clean package

---

Set env variables

Set c compiler settings C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\Build\vcvars64.bat
SET JAVA_HOME=path to GRAALVM
SET GRAALVM_HOME=path to GRAALVM

Use GraalVM for windows 64, java 24
GraalVM support only Visual Studio compiler!
Install visualstudio

Select the Desktop development with C++ checkbox in the main installation window. On the right side under Installation Details, make sure that the two requirements, Windows 11 SDK and MSVC (…) C++ x64/x86 build tools, are selected.
See Instructions

---

Gen native-config\reachability-metadata.json

%GRAALVM_HOME%\bin\java -agentlib:native-image-agent=config-output-dir=./native-config -jar target/SequrFly-1.0-SNAPSHOT-jar-with-dependencies.jar

---

build native image

%GRAALVM_HOME%\bin\native-image -jar target\SequrFly-1.0-SNAPSHOT-jar-with-dependencies.jar sequrfly --verbose -H:+ForeignAPISupport -H:+UnlockExperimentalVMOptions --no-fallback -H:ConfigurationFileDirectories=./native-config -Os -H:+ReportExceptionStackTraces -H:-ReduceImplicitExceptionStackTraceInformation -H:Class=org.mkura.seq.Main

---

run sequrfly.exe

[tnikolai2]

If use original org.eclipse.swt.win32.win32.x86_64 3.129.0

need also add native-config\reflect-config.json

[
  {
    "name": "sun.security.x509.X509CertInfo",
    "allDeclaredFields": true,
    "allDeclaredMethods": true,
    "allDeclaredConstructors": true
  },
  {
    "name": "sun.security.x509.SubjectKeyIdentifierExtension",
    "allDeclaredConstructors": true,
    "allDeclaredMethods": true,
    "allDeclaredFields": true
  },
  {
    "name": "sun.security.x509.BasicConstraintsExtension",
    "allDeclaredMethods": true,
    "allDeclaredFields": true
  },
  {
    "name": "sun.security.x509.X509CertImpl",
    "allDeclaredConstructors": true,
    "allDeclaredMethods": true,
    "allDeclaredFields": true
  }
]

But anyway will appear error:

Exception in thread "main" java.lang.NoSuchMethodError: org.eclipse.swt.browser.Edge$$Lambda/0x3f6355f8138fb3ac4de8a85d8a641fae0.Invoke(JJ)I
        at org.graalvm.nativeimage.builder/com.oracle.svm.core.jni.functions.JNIFunctions$Support.getMethodID(JNIFunctions.java:1853)
        at org.graalvm.nativeimage.builder/com.oracle.svm.core.jni.functions.JNIFunctions$Support.getMethodID(JNIFunctions.java:1838)
        at org.graalvm.nativeimage.builder/com.oracle.svm.core.jni.functions.JNIFunctions.GetMethodID(JNIFunctions.java:443)
        at org.eclipse.swt.internal.ole.win32.COM.CreateSwtWebView2Callback(Native Method)
        at org.eclipse.swt.browser.Edge.newCallback(Edge.java:235)
        at org.eclipse.swt.browser.Edge.callAndWait(Edge.java:255)
        at org.eclipse.swt.browser.Edge.createEnvironment(Edge.java:587)
        at org.eclipse.swt.browser.Edge.createInstance(Edge.java:634)
        at org.eclipse.swt.browser.Edge.create(Edge.java:630)
        at org.eclipse.swt.browser.Browser.<init>(Browser.java:99)
        at org.mkura.seq.Main.main(Main.java:26)
        at [email protected]/java.lang.invoke.LambdaForm$DMH/sa346b79c.invokeStaticInit(LambdaForm$DMH)

This cannot be fixed without changing Edge.java.

[HeikoKlare]

Thank you for the explanations!
From my side, this looks fine now.
@sratz do you have any comments here?

[sratz]

Looks good to me as well.

Would it make sense to add a small javadoc comment to the classes reminding that they should

• not be converted to lambdas
• ideally not be renamed to maximize compatibility
  ?

[HeikoKlare]

Would it make sense to add a small javadoc comment to the classes reminding that they should

• not be converted to lambdas
• ideally not be renamed to maximize compatibility
  ?

That definitely makes sense. I have just added comments to the two classes (also including references to this PR) and updated the PR accordingly.