pkgs/jni/test/global_env_test.dart - native - Git at Google

 // Copyright (c) 2022, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 import 'dart:io';

 import 'package:ffi/ffi.dart';
 import 'package:jni/jni.dart';
 import 'package:jni/src/jvalues.dart';
 import 'package:test/test.dart';

 import 'test_util/test_util.dart';

 const maxLongInJava = 9223372036854775807;

 void main() {
   // Running on Android through flutter, this plugin
   // will bind to Android runtime's JVM.
   // On other platforms eg Flutter desktop or Dart standalone
   // You need to manually create a JVM at beginning.
   //
   // On flutter desktop, the C wrappers are bundled, and helperPath param
   // is not required.
   //
   // On dart standalone, however, there's no way to bundle the wrappers.
   // You have to manually pass the path to the `dartjni` dynamic library.

   if (!Platform.isAndroid) {
     checkDylibIsUpToDate();
     Jni.spawnIfNotExists(dylibDir: "build/jni_libs", jvmOptions: ["-Xmx128m"]);
   }
   run(testRunner: test);
 }

 // We are factoring these tests into a run method which allows us to run same
 // tests with different environments. Eg: standalone and integration tests.
 void run({required TestRunnerCallback testRunner}) {
   // Tests in this file demonstrate how to use `GlobalJniEnv`, a thin
   // abstraction over JNIEnv in JNI C API. This can be used from multiple
   // threads, and converts all returned object references to global references,
   // so that you don't need to worry about whether your Dart code will be
   // scheduled on another thread.
   //
   // GlobalJniEnv wraps all methods of JNIEnv (UpperCamelCase, reflecting the
   // original name of the method) and provides few more extension methods
   // (lowerCamelCase).
   //
   // For examples of a higher level API, see `jni_object_tests.dart`.
   final env = Jni.env;
   testRunner('initDLApi', () {
     Jni.initDLApi();
   });

   testRunner('get JNI Version', () {
     expect(Jni.env.GetVersion(), isNot(equals(0)));
   });

   testRunner(
       'Manually lookup & call Integer.toHexString',
       () => using((arena) {
             // Method names on JniEnv* from C JNI API are capitalized
             // like in original, while other extension methods
             // follow Dart naming conventions.
             final integerClass =
                 env.FindClass("java/lang/Integer".toNativeChars(arena));
             // Refer JNI spec on how to construct method signatures
             // Passing wrong signature leads to a segfault
             final hexMethod = env.GetStaticMethodID(
                 integerClass,
                 "toHexString".toNativeChars(arena),
                 "(I)Ljava/lang/String;".toNativeChars(arena));

             for (var i in [1, 80, 13, 76, 11344]) {
               // if your argument is int, bool, or JObject (`Pointer<Void>`)
               // it can be directly placed in the list. To convert into different primitive
               // types, use JValue<Type> wrappers.
               final jres = env.CallStaticObjectMethodA(integerClass, hexMethod,
                   Jni.jvalues([JValueInt(i)], allocator: arena));

               // use asDartString extension method on Pointer<JniEnv>
               // to convert a String jobject result to string
               final res = env.toDartString(jres);
               expect(res, equals(i.toRadixString(16)));

               // Any object or class result from java is a local reference
               // and needs to be deleted explicitly.
               // Note that method and field IDs aren't local references.
               // But they are valid only until a reference to corresponding
               // java class exists.
               env.DeleteGlobalRef(jres);
             }
             env.DeleteGlobalRef(integerClass);
           }));

   testRunner("asJString extension method", () {
     const str = "QWERTY QWERTY";
     // convenience method that wraps
     // converting dart string to native string,
     // instantiating java string, and freeing the native string
     final jstr = env.toJStringPtr(str);
     expect(str, equals(env.toDartString(jstr)));
     env.DeleteGlobalRef(jstr);
   });

   testRunner(
       'GlobalJniEnv should catch exceptions',
       () => using((arena) {
             final integerClass =
                 env.FindClass("java/lang/Integer".toNativeChars(arena));
             final parseIntMethod = env.GetStaticMethodID(
                 integerClass,
                 "parseInt".toNativeChars(arena),
                 "(Ljava/lang/String;)I".toNativeChars(arena));
             final args = JValueArgs(["hello"], arena);
             expect(
                 () => env.CallStaticIntMethodA(
                     integerClass, parseIntMethod, args.values),
                 throwsA(isA<JniException>()));
           }));

   testRunner(
       "Convert back & forth between Dart & Java strings (UTF-8)",
       () => using((arena) {
             const str = "ABCD EFGH";
             final jstr = env.NewStringUTF(str.toNativeChars(arena));
             final jchars = env.GetStringUTFChars(jstr, nullptr);
             final jlen = env.GetStringUTFLength(jstr);
             final dstr = jchars.toDartString(length: jlen);
             env.ReleaseStringUTFChars(jstr, jchars);
             expect(str, equals(dstr));
             env.DeleteGlobalRef(jstr);
           }));

   testRunner(
       "Convert back & forth between Dart & Java strings (UTF-16)",
       () => using((arena) {
             const str = "ABCD EFGH";
             final jstr = env.NewString(str.toNativeUtf16().cast(), str.length);
             final jchars = env.GetStringChars(jstr, nullptr);
             final jlen = env.GetStringLength(jstr);
             final dstr = jchars.cast<Utf16>().toDartString(length: jlen);
             env.ReleaseStringChars(jstr, jchars);
             expect(str, equals(dstr));
             env.DeleteGlobalRef(jstr);
           }));

   testRunner(
       "Print something from Java",
       () => using((arena) {
             final system =
                 env.FindClass("java/lang/System".toNativeChars(arena));
             final field = env.GetStaticFieldID(
                 system,
                 "out".toNativeChars(arena),
                 "Ljava/io/PrintStream;".toNativeChars(arena));
             final out = env.GetStaticObjectField(system, field);
             final printStream = env.GetObjectClass(out);
             final println = env.GetMethodID(
                 printStream,
                 "println".toNativeChars(arena),
                 "(Ljava/lang/String;)V".toNativeChars(arena));
             const str = "\nHello World from JNI!";
             final jstr = env.toJStringPtr(str);
             env.CallVoidMethodA(out, println, Jni.jvalues([jstr]));
             env.deleteAllRefs([system, printStream, jstr]);
           }));
   testRunner(
       'Env create reference methods should retain their default behavior', () {
     final systemOut = Jni.retrieveStaticField<JObjectPtr>(
         "java/lang/System", "out", "Ljava/io/PrintStream;");
     var refType = env.GetObjectRefType(systemOut);
     expect(refType, equals(JObjectRefType.JNIGlobalRefType));
     final localRef = env.NewLocalRef(systemOut);
     refType = env.GetObjectRefType(localRef);
     expect(refType, equals(JObjectRefType.JNILocalRefType));
     final weakRef = env.NewWeakGlobalRef(systemOut);
     refType = env.GetObjectRefType(weakRef);
     expect(refType, equals(JObjectRefType.JNIWeakGlobalRefType));
     final globalRef = env.NewGlobalRef(localRef);
     refType = env.GetObjectRefType(globalRef);
     expect(refType, equals(JObjectRefType.JNIGlobalRefType));
     env.DeleteGlobalRef(globalRef);
     env.DeleteWeakGlobalRef(weakRef);
     env.DeleteLocalRef(localRef);
     env.DeleteGlobalRef(systemOut);
   });
   testRunner('long methods return long int without loss of precision', () {
     using((arena) {
       final longClass = env.FindClass("java/lang/Long".toNativeChars(arena));
       final maxField = env.GetStaticFieldID(
         longClass,
         'MAX_VALUE'.toNativeChars(arena),
         'J'.toNativeChars(arena),
       );
       final maxValue = env.GetStaticLongField(longClass, maxField);
       expect(maxValue, equals(maxLongInJava));
       env.DeleteGlobalRef(longClass);
     });
   });

   testRunner('class <-> object methods', () {
     using((arena) {
       final systemOut = Jni.retrieveStaticField<JObjectPtr>(
           "java/lang/System", "out", "Ljava/io/PrintStream;");
       final systemErr = Jni.retrieveStaticField<JObjectPtr>(
           "java/lang/System", "err", "Ljava/io/PrintStream;");
       final outClass = env.GetObjectClass(systemOut);
       expect(env.IsInstanceOf(systemOut, outClass), isTrue);
       expect(env.IsInstanceOf(systemErr, outClass), isTrue);
       final errClass = env.GetObjectClass(systemErr);
       expect(env.IsSameObject(outClass, errClass), isTrue);
       env.deleteAllRefs([systemOut, systemErr, outClass, errClass]);
     });
   });
 }
	// Copyright (c) 2022, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	import 'dart:io';

	import 'package:ffi/ffi.dart';
	import 'package:jni/jni.dart';
	import 'package:jni/src/jvalues.dart';
	import 'package:test/test.dart';

	import 'test_util/test_util.dart';

	const maxLongInJava = 9223372036854775807;

	void main() {
	// Running on Android through flutter, this plugin
	// will bind to Android runtime's JVM.
	// On other platforms eg Flutter desktop or Dart standalone
	// You need to manually create a JVM at beginning.
	//
	// On flutter desktop, the C wrappers are bundled, and helperPath param
	// is not required.
	//
	// On dart standalone, however, there's no way to bundle the wrappers.
	// You have to manually pass the path to the `dartjni` dynamic library.

	if (!Platform.isAndroid) {
	checkDylibIsUpToDate();
	Jni.spawnIfNotExists(dylibDir: "build/jni_libs", jvmOptions: ["-Xmx128m"]);
	}
	run(testRunner: test);
	}

	// We are factoring these tests into a run method which allows us to run same
	// tests with different environments. Eg: standalone and integration tests.
	void run({required TestRunnerCallback testRunner}) {
	// Tests in this file demonstrate how to use `GlobalJniEnv`, a thin
	// abstraction over JNIEnv in JNI C API. This can be used from multiple
	// threads, and converts all returned object references to global references,
	// so that you don't need to worry about whether your Dart code will be
	// scheduled on another thread.
	//
	// GlobalJniEnv wraps all methods of JNIEnv (UpperCamelCase, reflecting the
	// original name of the method) and provides few more extension methods
	// (lowerCamelCase).
	//
	// For examples of a higher level API, see `jni_object_tests.dart`.
	final env = Jni.env;
	testRunner('initDLApi', () {
	Jni.initDLApi();
	});

	testRunner('get JNI Version', () {
	expect(Jni.env.GetVersion(), isNot(equals(0)));
	});

	testRunner(
	'Manually lookup & call Integer.toHexString',
	() => using((arena) {
	// Method names on JniEnv* from C JNI API are capitalized
	// like in original, while other extension methods
	// follow Dart naming conventions.
	final integerClass =
	env.FindClass("java/lang/Integer".toNativeChars(arena));
	// Refer JNI spec on how to construct method signatures
	// Passing wrong signature leads to a segfault
	final hexMethod = env.GetStaticMethodID(
	integerClass,
	"toHexString".toNativeChars(arena),
	"(I)Ljava/lang/String;".toNativeChars(arena));

	for (var i in [1, 80, 13, 76, 11344]) {
	// if your argument is int, bool, or JObject (`Pointer<Void>`)
	// it can be directly placed in the list. To convert into different primitive
	// types, use JValue<Type> wrappers.
	final jres = env.CallStaticObjectMethodA(integerClass, hexMethod,
	Jni.jvalues([JValueInt(i)], allocator: arena));

	// use asDartString extension method on Pointer<JniEnv>
	// to convert a String jobject result to string
	final res = env.toDartString(jres);
	expect(res, equals(i.toRadixString(16)));

	// Any object or class result from java is a local reference
	// and needs to be deleted explicitly.
	// Note that method and field IDs aren't local references.
	// But they are valid only until a reference to corresponding
	// java class exists.
	env.DeleteGlobalRef(jres);
	}
	env.DeleteGlobalRef(integerClass);
	}));

	testRunner("asJString extension method", () {
	const str = "QWERTY QWERTY";
	// convenience method that wraps
	// converting dart string to native string,
	// instantiating java string, and freeing the native string
	final jstr = env.toJStringPtr(str);
	expect(str, equals(env.toDartString(jstr)));
	env.DeleteGlobalRef(jstr);
	});

	testRunner(
	'GlobalJniEnv should catch exceptions',
	() => using((arena) {
	final integerClass =
	env.FindClass("java/lang/Integer".toNativeChars(arena));
	final parseIntMethod = env.GetStaticMethodID(
	integerClass,
	"parseInt".toNativeChars(arena),
	"(Ljava/lang/String;)I".toNativeChars(arena));
	final args = JValueArgs(["hello"], arena);
	expect(
	() => env.CallStaticIntMethodA(
	integerClass, parseIntMethod, args.values),
	throwsA(isA<JniException>()));
	}));

	testRunner(
	"Convert back & forth between Dart & Java strings (UTF-8)",
	() => using((arena) {
	const str = "ABCD EFGH";
	final jstr = env.NewStringUTF(str.toNativeChars(arena));
	final jchars = env.GetStringUTFChars(jstr, nullptr);
	final jlen = env.GetStringUTFLength(jstr);
	final dstr = jchars.toDartString(length: jlen);
	env.ReleaseStringUTFChars(jstr, jchars);
	expect(str, equals(dstr));
	env.DeleteGlobalRef(jstr);
	}));

	testRunner(
	"Convert back & forth between Dart & Java strings (UTF-16)",
	() => using((arena) {
	const str = "ABCD EFGH";
	final jstr = env.NewString(str.toNativeUtf16().cast(), str.length);
	final jchars = env.GetStringChars(jstr, nullptr);
	final jlen = env.GetStringLength(jstr);
	final dstr = jchars.cast<Utf16>().toDartString(length: jlen);
	env.ReleaseStringChars(jstr, jchars);
	expect(str, equals(dstr));
	env.DeleteGlobalRef(jstr);
	}));

	testRunner(
	"Print something from Java",
	() => using((arena) {
	final system =
	env.FindClass("java/lang/System".toNativeChars(arena));
	final field = env.GetStaticFieldID(
	system,
	"out".toNativeChars(arena),
	"Ljava/io/PrintStream;".toNativeChars(arena));
	final out = env.GetStaticObjectField(system, field);
	final printStream = env.GetObjectClass(out);
	final println = env.GetMethodID(
	printStream,
	"println".toNativeChars(arena),
	"(Ljava/lang/String;)V".toNativeChars(arena));
	const str = "\nHello World from JNI!";
	final jstr = env.toJStringPtr(str);
	env.CallVoidMethodA(out, println, Jni.jvalues([jstr]));
	env.deleteAllRefs([system, printStream, jstr]);
	}));
	testRunner(
	'Env create reference methods should retain their default behavior', () {
	final systemOut = Jni.retrieveStaticField<JObjectPtr>(
	"java/lang/System", "out", "Ljava/io/PrintStream;");
	var refType = env.GetObjectRefType(systemOut);
	expect(refType, equals(JObjectRefType.JNIGlobalRefType));
	final localRef = env.NewLocalRef(systemOut);
	refType = env.GetObjectRefType(localRef);
	expect(refType, equals(JObjectRefType.JNILocalRefType));
	final weakRef = env.NewWeakGlobalRef(systemOut);
	refType = env.GetObjectRefType(weakRef);
	expect(refType, equals(JObjectRefType.JNIWeakGlobalRefType));
	final globalRef = env.NewGlobalRef(localRef);
	refType = env.GetObjectRefType(globalRef);
	expect(refType, equals(JObjectRefType.JNIGlobalRefType));
	env.DeleteGlobalRef(globalRef);
	env.DeleteWeakGlobalRef(weakRef);
	env.DeleteLocalRef(localRef);
	env.DeleteGlobalRef(systemOut);
	});
	testRunner('long methods return long int without loss of precision', () {
	using((arena) {
	final longClass = env.FindClass("java/lang/Long".toNativeChars(arena));
	final maxField = env.GetStaticFieldID(
	longClass,
	'MAX_VALUE'.toNativeChars(arena),
	'J'.toNativeChars(arena),
	);
	final maxValue = env.GetStaticLongField(longClass, maxField);
	expect(maxValue, equals(maxLongInJava));
	env.DeleteGlobalRef(longClass);
	});
	});

	testRunner('class <-> object methods', () {
	using((arena) {
	final systemOut = Jni.retrieveStaticField<JObjectPtr>(
	"java/lang/System", "out", "Ljava/io/PrintStream;");
	final systemErr = Jni.retrieveStaticField<JObjectPtr>(
	"java/lang/System", "err", "Ljava/io/PrintStream;");
	final outClass = env.GetObjectClass(systemOut);
	expect(env.IsInstanceOf(systemOut, outClass), isTrue);
	expect(env.IsInstanceOf(systemErr, outClass), isTrue);
	final errClass = env.GetObjectClass(systemErr);
	expect(env.IsSameObject(outClass, errClass), isTrue);
	env.deleteAllRefs([systemOut, systemErr, outClass, errClass]);
	});
	});
	}