Something weird about static imports

[Sankaranarayanan Viswanathan]

I have two java source files as below:

Test2.java

package com;

public class Test2 {
	public int data = 10;
	
	public static Test2 func() {return new Test2();}
}

Test.java

package com.sankar;

import static com.Test2.*;

class Test {
	public static void main(String[] args) {
		Test2 t2 = null;  //--> Line 1
		System.out.println(func().data);  //--> Line 2
	}
}

My problem is I don't understand why Line 1 does not compile, but Line 2 compiles okay. The static import in Test.java does not import the class Test2 itself, but only the static members of Test2. If that is true, why does Line 2 work - Doesn't the java compiler need Test2 to be visible before it could access its instance member data? If you comment out Line 1, you will see that Test.java compiles and executes.

[Stephan van Hulst]

You don't need import statements unless you're actually using the name of whatever it is you're using. You're not using the name Test2 in line 2, so you don't need to import it.

Think about it. Import statements are used to tell the compiler where to find the things you're referring to.

[Sankaranarayanan Viswanathan]

But, then this example below causes a compile error. I am not referring to the 'Inner' class explicitly, but yet I receive a compile error:

class Outer {
	private class Inner {
		public int data = 10;
	}
	
	Inner getInner() {
		return new Inner();
	}
}

class Test {
	public static void main(String[] args) {
		Outer out = new Outer();
		
		System.out.println(out.getInner().data);
	}
}

But, look at this one below which actually compiles and produces an output of "Inner: 10":

class Outer {
	private class Inner {
		public int data = 10;
		
		public String toString() {
			return "Inner: " + data;
		}
	}
	
	Inner getInner() {
		return new Inner();
	}
}

class Test {
	public static void main(String[] args) {
		Outer out = new Outer();
		
		System.out.println(out.getInner());
	}
}

Why does this work?

[Stephan van Hulst]

The first fails because you're trying to access a field of a private class. Inner is private, so Test knows nothing about it. This has nothing to do with import statements.

[maganti suryanarayana]

What is there in line 2 just a blank place.

[Stephan van Hulst]

Look at the comments in lines 7 and 8 of Test.