jni/jni_test.go

// +build !android
//go:generate javac test/AClass.java test/AClass2.java

package jni

import (
	"sync"
	"testing"
	"unsafe"
)

var (
	vm     JVM
	vmOnce sync.Once
)

func TestCreateJVM(t *testing.T) {
	// Do not try to create more than one JVM
	vmOnce.Do(func() {
		res := CreateJavaVM()
		if res.jvm == nil {
			t.Errorf("CreateJavaVM() returned nil")
		} else {
			vm = res
		}
	})
}

func TestDo(t *testing.T) {
	// create an invalid JVM
	vm2 := JVMFor(uintptr(unsafe.Pointer(vm.jvm)))
	err := Do(vm2, func(env Env) error {
		return nil
	})
	if err != nil {
		t.Errorf("Do() returned an error")
	}
}

func TestFindClass(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		if cls == 0 {
			t.Errorf("Class is nil")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("No exception for class not found")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	err = Do(vm, func(env Env) error {
		cls := FindClass(env, "test/NoSuchClass")
		if cls == 0 {
			t.Errorf("Class is nil")
		}
		return nil
	})
}

func TestEnvFor(t *testing.T) {
	err := Do(vm, func(env Env) error {
		env2 := EnvFor(uintptr(unsafe.Pointer(env.env)))
		cls := FindClass(env2, "test/AClass")
		if cls == 0 {
			t.Errorf("Class is nil")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestGetMethodID(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestNewObject(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		if err != nil {
			t.Errorf("NewObject raised exception")
		}
		if inst == 0 {
			t.Errorf("NewObject returned nil")
		}
		inst = NewGlobalRef(env, inst)
		if inst == 0 {
			t.Errorf("NewGlobalRef returned nil")
		}
		DeleteGlobalRef(env, inst)
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestIsSameObject(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		if !IsSameObject(env, inst, inst) {
			t.Errorf("Object is not the same as itself")
		}
		inst2, err := NewObject(env, cls, mid)
		if err != nil {
			t.Errorf("Object is nil")
		}
		if IsSameObject(env, inst, inst2) {
			t.Errorf("Different objects are the same")
		}
		inst2 = NewLocalRef(env, inst)
		if !IsSameObject(env, inst, inst2) {
			t.Errorf("New local ref is not the same as original object")
		}
		DeleteLocalRef(env, inst)
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestStaticMethod(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("GetStaticMethodID() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		GetStaticMethodID(env, cls, "noSuchMethod", "()V")
		return nil
	})
}

func TestStaticIntMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		mid = GetStaticMethodID(env, cls, "GetStaticInt", "()I")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallStaticIntMethod(env, cls, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 100 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 100)
		}
		return err
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestStaticObjectMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		mid = GetStaticMethodID(env, cls, "GetStaticObject", "()Ljava/lang/Object;")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		_, err := CallStaticObjectMethod(env, cls, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		return err
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestMethod(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("GetMethodID() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		GetMethodID(env, cls, "noSuchMethod", "()V")
		return nil
	})
}

func TestIntMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetInt", "()I")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallIntMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 101 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 0)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestBooleanMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetBoolean", "()Z")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallBooleanMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if !res {
			t.Errorf("Method returned %v, not expected value of %v.", res, true)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestByteMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetByte", "()B")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallByteMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 127 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 127)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestCharMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetChar", "()C")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallCharMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 65432 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 65432)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestShortMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetShort", "()S")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallShortMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 512 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 512)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestLongMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetLong", "()J")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallLongMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 1<<33 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 1<<33)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestFloatMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetFloat", "()F")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallFloatMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 4.321 {
			t.Errorf("Method returned %f, not expected value of %f.", res, 4.321)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestDoubleMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "GetDouble", "()D")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		res, err := CallDoubleMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		if res != 5.4321 {
			t.Errorf("Method returned %f, not expected value of %f.", res, 5.4321)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestVoidMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "IncInt", "()V")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		err = CallVoidMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestVoidMethod2(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "SetInt", "(I)V")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		err = CallVoidMethod(env, inst, mid, 5)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		mid = GetMethodID(env, cls, "GetInt", "()I")
		res, err := CallIntMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation falied")
		}
		if res != 5 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 5)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestVoidMethod3(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, err := NewObject(env, cls, mid)
		mid = GetMethodID(env, cls, "AddInts", "(II)V")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		err = CallVoidMethod(env, inst, mid, 9, 11)
		if err != nil {
			t.Errorf("Method invocation failed")
		}
		mid = GetMethodID(env, cls, "GetInt", "()I")
		res, err := CallIntMethod(env, inst, mid)
		if err != nil {
			t.Errorf("Method invocation falied")
		}
		if res != 20 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 20)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestStaticVoidMethod(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetStaticMethodID(env, cls, "SetStaticInt", "(I)V")
		if mid == nil {
			t.Errorf("MethodID is nil")
		}
		err := CallStaticVoidMethod(env, cls, mid, 200)
		if err != nil {
			t.Errorf("Method invocation failed: %s", err)
		}
		mid = GetStaticMethodID(env, cls, "GetStaticInt", "()I")
		res, err := CallStaticIntMethod(env, cls, mid)
		if err != nil {
			t.Errorf("Method invocation falied: %s", err)
		}
		if res != 200 {
			t.Errorf("Method returned %d, not expected value of %d.", res, 200)
		}
		mid = GetStaticMethodID(env, cls, "SetStaticInt", "(I)V")
		err = CallStaticVoidMethod(env, cls, mid, 100)
		if err != nil {
			t.Errorf("Method invocation failed: %s", err)
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestGetObjectClass(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("GetObjectClass() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	err := Do(vm, func(env Env) error {
		GetObjectClass(env, Object(unsafe.Pointer(uintptr(0))))
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestGetObjectClass2(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		cls2 := GetObjectClass(env, inst)
		if cls2 == 0 {
			t.Errorf("GetObjectClass returned nil")
		}
		if !IsInstanceOf(env, inst, cls2) {
			t.Errorf("IsInstanceOf failed")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestIsInstanceOf(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("IsInstanceOf() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	err := Do(vm, func(env Env) error {
		IsInstanceOf(env, Object(0), Class(0))
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestIsInstanceOf2(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("IsInstanceOf() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		IsInstanceOf(env, inst, Class(0))
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestIsInstanceOf3(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		cls = FindClass(env, "java/lang/String")
		if IsInstanceOf(env, inst, cls) {
			t.Errorf("IsInstanceOf() returned wrong value")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestField(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		fid := GetFieldID(env, cls, "in", "I")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r1 := GetIntField(env, inst, fid)
		if r1 != 101 {
			t.Errorf("Method returned %d, not expected value of %d.", r1, 0)
		}
		fid = GetFieldID(env, cls, "bl", "Z")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r2 := GetBooleanField(env, inst, fid)
		if r2 != false {
			t.Errorf("Boolean field value is incorrect")
		}
		fid = GetFieldID(env, cls, "bt", "B")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r3 := GetByteField(env, inst, fid)
		if r3 != 'c' {
			t.Errorf("Byte field value is incorrect")
		}
		fid = GetFieldID(env, cls, "ch", "C")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r4 := GetCharField(env, inst, fid)
		if r4 != 'd' {
			t.Errorf("Char field value is incorrect")
		}
		fid = GetFieldID(env, cls, "obj", "Ljava/lang/Object;")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r5 := GetObjectField(env, inst, fid)
		if r5 == 0 {
			t.Errorf("Object field value is incorrect")
		}
		fid = GetFieldID(env, cls, "sh", "S")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r6 := GetShortField(env, inst, fid)
		if r6 != 11 {
			t.Errorf("Short field value is incorrect")
		}
		fid = GetFieldID(env, cls, "lo", "J")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r7 := GetLongField(env, inst, fid)
		if r7 != 1001 {
			t.Errorf("Long field value is incorrect")
		}
		fid = GetFieldID(env, cls, "fl", "F")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r8 := GetFloatField(env, inst, fid)
		if r8 != 2.2 {
			t.Errorf("Float field value is incorrect")
		}
		fid = GetFieldID(env, cls, "db", "D")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r9 := GetDoubleField(env, inst, fid)
		if r9 != 1001.1001 {
			t.Errorf("Double field value is incorrect")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestField2(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("GetFieldID() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		GetFieldID(env, cls, "noSuchField", "I")
		return nil
	})
}

func TestStaticField(t *testing.T) {
	err := Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		fid := GetStaticFieldID(env, cls, "staticint", "I")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r1 := GetStaticIntField(env, cls, fid)
		if r1 != 100 {
			t.Errorf("Method returned %d, not expected value of %d.", r1, 100)
		}
		fid = GetStaticFieldID(env, cls, "staticbl", "Z")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r2 := GetStaticBooleanField(env, cls, fid)
		if r2 != true {
			t.Errorf("Boolean field value is incorrect")
		}
		fid = GetStaticFieldID(env, cls, "staticbt", "B")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r3 := GetStaticByteField(env, cls, fid)
		if r3 != 'a' {
			t.Errorf("Byte field value is incorrect")
		}
		fid = GetStaticFieldID(env, cls, "staticch", "C")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r4 := GetStaticCharField(env, cls, fid)
		if r4 != 'b' {
			t.Errorf("Char field value is incorrect")
		}
		fid = GetStaticFieldID(env, cls, "staticobj", "Ljava/lang/Object;")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r5 := GetStaticObjectField(env, cls, fid)
		if r5 == 0 {
			t.Errorf("Object field value is incorrect")
		}
		fid = GetStaticFieldID(env, cls, "staticsh", "S")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r6 := GetStaticShortField(env, cls, fid)
		if r6 != 10 {
			t.Errorf("Short field value is incorrect")
		}
		fid = GetStaticFieldID(env, cls, "staticlo", "J")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r7 := GetStaticLongField(env, cls, fid)
		if r7 != 1000 {
			t.Errorf("Long field value is incorrect")
		}
		fid = GetStaticFieldID(env, cls, "staticfl", "F")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r8 := GetStaticFloatField(env, cls, fid)
		if r8 != 1.1 {
			t.Errorf("Float field value is incorrect")
		}
		fid = GetStaticFieldID(env, cls, "staticdb", "D")
		if fid == nil {
			t.Errorf("FieldID is nil")
		}
		r9 := GetStaticDoubleField(env, cls, fid)
		if r9 != 1000.0001 {
			t.Errorf("Double field value is incorrect")
		}
		return nil
	})
	if err != nil {
		t.Errorf("Error: %s", err)
	}
}

func TestStaticField2(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("GetStaticField() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		fid := GetStaticFieldID(env, cls, "FieldNotFound", "I")
		GetStaticIntField(env, cls, fid)
		return nil
	})
}

func TestByteArray(t *testing.T) {
	arr := []byte{'a', 'b', 'c'}
	Do(vm, func(env Env) error {
		jarr := NewByteArray(env, arr)
		arr2 := GetByteArrayElements(env, jarr)
		if arr2[0] != 'a' ||
			arr2[1] != 'b' ||
			arr2[2] != 'c' ||
			len(arr2) != 3 {
			t.Errorf("GetByteArrayElements() failed")
		}
		return nil
	})
}

func TestObjectArray(t *testing.T) {
	Do(vm, func(env Env) error {
		cls := FindClass(env, "java/lang/Object")
		if cls == 0 {
			t.Errorf("Class is nil")
		}

		strings := []string{
			"item1",
			"item2",
		}

		arr := NewObjectArray(env, Size(len(strings)), cls, 0)
		for i, s := range strings {
			jstring := JavaString(env, s)
			err := SetObjectArrayElement(env, arr, Size(i), Object(jstring))
			if err != nil {
				t.Errorf("SetObjectArrayElement at index %d raised exception", i)
			}
		}

		for i, s := range strings {
			r, err := GetObjectArrayElement(env, arr, Size(i))
			if err != nil {
				t.Errorf("GetObjectArrayElement at index %d raised exception", i)
			}

			retrieved := GoString(env, String(r))
			if s != retrieved {
				t.Errorf("Expected item %d to be '%s' but instead was '%s'", i, s, retrieved)
			}
		}
		return nil
	})
}

func TestClassLoaderFor(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("ClassLoaderFor() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	Do(vm, func(env Env) error {
		cls := FindClass(env, "java/lang/Object")
		if cls == 0 {
			t.Errorf("Class is nil")
		}
		mid := GetMethodID(env, cls, "<init>", "()V")
		if mid == nil {
			t.Errorf("Method ID is nil")
		}
		inst, err := NewObject(env, cls, mid)
		if err != nil {
			t.Errorf("NewObject raised exception")
		}
		if inst == 0 {
			t.Errorf("NewObject returned nil")
		}
		ClassLoaderFor(env, inst)
		return nil
	})
}

func TestClassLoaderFor2(t *testing.T) {
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		cl := ClassLoaderFor(env, inst)
		if cl == 0 {
			t.Errorf("ClassLoaderFor() returned nil")
		}
		return nil
	})
}

func TestClassLoaderFor3(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("ClassLoaderFor() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	Do(vm, func(env Env) error {
		cls := FindClass(env, "java/lang/Object")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		cl := ClassLoaderFor(env, inst)
		if cl == 0 {
			t.Errorf("ClassLoaderFor() returned nil")
		}
		return nil
	})
}

func TestClassLoaderFor4(t *testing.T) {
	defer func() {
		if r := recover(); r == nil {
			t.Errorf("ClassLoaderFor() did not panic")
		} else {
			t.Logf("Panic: %s", r)
		}
	}()
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass2")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		cl := ClassLoaderFor(env, inst)
		if cl == 0 {
			t.Errorf("ClassLoaderFor() returned nil")
		}
		return nil
	})
}

func TestLoadClass(t *testing.T) {
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		cl := ClassLoaderFor(env, inst)
		if cl == 0 {
			t.Errorf("ClassLoaderFor() returned nil")
		}
		cls, err := LoadClass(env, cl, "java.lang.String")
		if err != nil {
			t.Errorf("LoadClass() returned error: %s", err)
		}
		if cls == 0 {
			t.Errorf("LoadClass() failed")
		}
		return nil
	})
}

func TestLoadClass2(t *testing.T) {
	Do(vm, func(env Env) error {
		cls := FindClass(env, "test/AClass")
		mid := GetMethodID(env, cls, "<init>", "()V")
		inst, _ := NewObject(env, cls, mid)
		_, err := LoadClass(env, inst, "java.lang.String")
		if err == nil {
			t.Errorf("LoadClass() did not return an error")
		} else {
			t.Logf("Error: %s", err)
		}
		return nil
	})
}

func TestJavaString(t *testing.T) {
	Do(vm, func(env Env) error {
		jstr := JavaString(env, "")
		if jstr != 0 {
			t.Errorf("String is not nil")
		}
		gstr := GoString(env, jstr)
		if gstr != "" {
			t.Errorf("String is not empty")
		}

		jstr = JavaString(env, "test string")
		gstr = GoString(env, jstr)
		if gstr != "test string" {
			t.Errorf("Strings do not match")
		}
		return nil
	})
}