第十四道Java小问题

以下哪段程序不会在编译时出错

1)
A.java的内容如下

package p1;

public class A {
    private int i = 0;
    int j = 5;

    protected void call() {
        i = 5;
        A a = new A();
        a.i = 8;
    }
}

 

2)
A.java的内容如下

pacakge p1;

public class A {
    private int i = 0;
    int j = 5;

    protected void call() {
    }
}

 

B.java的内容如下

package p2;
import p1;

public class B extends A {

    protected void call() {
        j = 9;

    }
}

 

3)

 

A.java的内容如下

pacakge p1;

public class A {
    private int i = 0;
    int j = 5;

    protected void call() {
    }
}

 

B.java的内容如下

package p2;
import p1;

public class B extends A {

    protected void f() {
        A a = new A();
        a.call();

    }
}

 

4)

 

A.java的内容如下

pacakge p1;

public class A {
    private int i = 0;
    int j = 5;

    protected void call() {
    }
}

 

B.java的内容如下

package p2;
import p1;

public class B extends A {
    protected void call() {
    }
}

 

 

 

C.java的内容如下

package p1;
import p2;

public class C extends A {
    protected void f() {
        A a = new B();
        a.call();
    }
}