英文:
Non nullable type throwing KotlinNullPointerException
问题
我在Java中有以下的类：
public class MyZClass1_ {
public int x = 100;
}
然后在Kotlin中对它进行了测试：
@TestInstance(TestInstance.Lifecycle.PER_CLASS)
class _01_SO_KotlinReflectionAccessorReturnTypeKotlinNull {
@Test
fun demonstrate_returnTypeReflectionOfAccessorFunctionInJavaClassThrowsKotlinNull() {
val zClass1_ = MyZClass1_::class
for (declaredProperty in zClass1_.declaredMemberProperties) {
val propertyGetter = declaredProperty.getter
assertNotNull(propertyGetter)
try {
val returnType = propertyGetter.returnType
} catch (ex: KotlinNullPointerException) {
ex.printStackTrace()
}
}
}
}
- `propertyGetter` 不为 null（如断言所示）
- `propertyGetter.returnType` 有一个非空类型 `KType`
- 问题是这一行 `val returnType = propertyGetter.returnType` 抛出了 `KotlinNullPointerException`。
- 为什么会这样？我是否漏掉了什么？
英文:
I have the following class in java
public class MyZClass1_ {
public int x = 100;
}
and that test in kotlin
@TestInstance(TestInstance.Lifecycle.PER_CLASS)
class _01_SO_KotlinReflectionAccessorReturnTypeKotlinNull {
@Test
fun demonstrate_returnTypeReflectionOfAccessorFunctionInJavaClassThrowsKotlinNull() {
val zClass1_ = MyZClass1_::class
for (declaredProperty in zClass1_.declaredMemberProperties) {
val propertyGetter = declaredProperty.getter
assertNotNull(propertyGetter)
try {
val returnType = propertyGetter.returnType
} catch (ex: KotlinNullPointerException) {
ex.printStackTrace()
}
}
}
}
propertyGetteris not null (as asserted)propertyGetter.returnTypehas a non-nullable typeKType- The problem is that the line
val returnType = propertyGetter.returnTypethrows aKotlinNullPointerException. - Why is that? Am i missing something?
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