Please explain to me the simple language, the actions in the code.

[Jolied]

public class Main {
    public static void main(String[] args) {

        Cat cat = new Cat();

        System.out.println(cat.name);
        changeName(cat);
        System.out.println(cat.name);
    }

    public static void changeName(Cat cat) {
        cat.name = "Jerry";
    }

    public static class Cat {        
        String name = "Tom";
    }
}

[elysha]

starting with method. main, this is the entry point at which the programme begins.

public static void main(String[] args) {  

Then create a class object Cat by name cat

Cat cat = new Cat();  

Look at the class.

 public static class Cat {        
        String name = "Tom";
    }    

Class has one characteristic, a string field under the name namein which the value is immediately recorded "Tom"♪

We're going to put the field in the console. name Previous class object Cat

System.out.println(cat.name);     

caused by a static method which, in the parameters, adopts any class object Сat and change the meaning of the field name ♪ "Jerry"

 public static void changeName(Cat cat) {
        cat.name = "Jerry";
    }

And at the end, we'll get the new meaning of the field. name facility cat

System.out.println(cat.name);