[JAVA] I checked this

When referencing the outer class from the inner class External class name.this There seems to be a notation of, so I did a little research.

First, I came up with


public class Main {
    public static void main(String []args) {
        TestThis t = new TestThis();
        t.this.hp = 10;///
    }


    public class TestThis {
        int hp;
        int mp;
        String name;
    }

}

I wondered if this was the case

t.this.hp = 10;

This part is eclipse, and t cannot be resolved into a mold. Do you want to create a t class? Came out.

If t.hp = 10 ;, what's ok?

Apparently, the interpretation of the inner class was wrong,

class out~{ class in~{ } }

Image of. Based on this, experiment again with Eclipse.

public class Main {
    public static void main(String []args) {
    	Outer o =  new Outer();
    	Outer.Inner oi = o.new Inner();
    	oi.innerPrint();
    }
    
    public class Outer{
	
        int outerhp = 10;
	
        public class Inner{
		
            public void innerPrint() {
                System.out.println(Outer.this.outerhp);
            }
		
        }
	
    }

}

Still an error According to Eclipse There is no accessible instance of type Main. You must limit the allocation on an enclosing instance of type Main (for example, x.new A (), where x is an instance of Main).

When I looked it up, I didn't understand a little.

public class Main {
    public static void main(String []args) {
    	Outer o =  new Outer();
    	Outer.Inner oi = o.new Inner();
    	oi.innerPrint();
    }

    public static class Outer{

        int outerhp = 10;

        public class Inner{

            public void innerPrint() {
                System.out.println(Outer.this.outerhp);
            }

        }

    }

}

From the result, it works without error. (Outer class is static)

It looks like something close to a bug, so I'd like to investigate it tomorrow. http://d.hatena.ne.jp/chiheisen/20110502/1304272928 Looking at the position of the indent, I feel like I'm saying something different from my code. main (String [] args) is in Outer ... I have never written such a code.

Outer.Inner oi = o.new Inner();

I think I saw this new way in a book before. Once again, you can read that book with a tree stump on the cover.

Every time I correct the indentation, it shifts lol I wonder if the format is different if I pasted it from Eclipse.

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