Fix glue functions as public in JNI mode

[sidepelican]

In release builds (JNI mode), Java-linked Swift functions were being stripped from the dynamic library, It might be because of dead code elimination.

I have added the public modifier to these functions to match the behavior of FFM mode and ensure they are properly exported.

• before(In Samples/SwiftJavaExtractJNISampleApp)

❯ swiftly run +swift-6.3-DEVELOPMENT-SNAPSHOT-2026-01-03-a swift build -c release --swift-sdk aarch64-unknown-linux-android28
❯ nm -D .build/aarch64-unknown-linux-android28/release/libMySwiftLibrary.so | grep Java_
(no output)

• after

❯ swiftly run +swift-6.3-DEVELOPMENT-SNAPSHOT-2026-01-03-a swift build -c release --swift-sdk aarch64-unknown-linux-android28
❯ nm -D .build/aarch64-unknown-linux-android28/release/libMySwiftLibrary.so | grep Java_
00000000000bb544 T $s14MySwiftLibrary023Java_com_example_swift_aB18Class__00024init__11environment04thisH0s5Int64VSpySPySo18JNINativeInterfaceVGSgGSg_SvtF
00000000000bb600 T $s14MySwiftLibrary023Java_com_example_swift_aB18Class__00024sum__J11environment04thisH04selfs5Int64VSpySPySo18JNINativeInterfaceVGSgGSg_SvAGtF
00000000000bb650 T $s14MySwiftLibrary023Java_com_example_swift_aB19Class__00024copy__J11environment04thisH04selfs5Int64VSpy
...

[ktoso]

Yeah, the missing public would be able to cause such a thing. Thanks for the pull request!

[sidepelican]

My very tiny library worked fine with this,
but it might be public necessary here too?

swift-java/Sources/SwiftJava/JNI.swift

Line 57 in 1c73ff0

func SwiftJava_JNI_OnLoad(javaVM: JavaVMPointer, reserved: UnsafeMutableRawPointer) -> jint {

[ktoso]

I would not mind making it public in abundance if caution.

[sidepelican]

Now JNI_OnLoad is also included.

• before

❯ nm -D .build/aarch64-unknown-linux-android28/release/libSwiftJava.so | grep JNI_OnLoad 
(no output)

• after

❯ nm -D .build/aarch64-unknown-linux-android28/release/libSwiftJava.so | grep JNI_OnLoad
00000000000c6060 T $s9SwiftJava0aB11_JNI_OnLoad6javaVM8reserveds5Int32VSpySPySo18JNIInvokeInterfaceVGSgG_SvtF
00000000000c605c T JNI_OnLoad

[ktoso]

Thank you!

this did make me think that it likely was necessaey to begin with. Thank you!