崔

```java

public class Main {

public static void main(String[] args) {

Object obj = new String("Hello");

System.out.println(obj.getClass());

}

}

```

```java

class MyClass { int value;}

class Test {

public static void changeValue(MyClass obj) {

obj.value = 10;

}

}

public class Main {

public static void main(String[] args) {

MyClass obj = new MyClass();

obj.value = 5;

Test.changeValue(obj);

System.out.println(obj.value);

}

}

```

```java

class MyClass {

static int x = 5;

}

public class Main {

public static void main(String[] args) {

MyClass obj1 = new MyClass();

MyClass obj2 = new MyClass();

obj1.x = 10;

System.out.println(obj2.x);

}

}

```