Java Basic (four) face question

Interview questions:

• Construct code blocks, construct methods, and prioritize static code?
• Static code blocks > Constructing code blocks > Construction Methods

Interview question: What is the difference between overload and override?
Overload: Method Overloading
Method names, parameters differ, and return values are not related
Different parameters:
1) different number of parameters
2) different parameter types
Override: Method Override (subclass defines a method declaration that is the same as a parent class)
Continue to use in the

2 about the difference between this and super?
This: Represents the object of the current class
Super: Represents the parent class spatial identity, which is understood as an object representing the parent class

    应用场景:            this:            super:                    成员变量                            this.成员变量                            super.成员变量                    成员方法                            this.成员方法()                            super.成员方法();                    构造方法                            this()/this("..")    面试题:

• Local internal classes Access local variables, then problems occur? (Jdk7 previously included jdk7, this problematic)
• Error, need to add final decoration to local variables ...
• Why does this local variable have to be final decorated?

• The local variable should also be used in the inner class, change the variable to a fixed value, always exist in memory, and invoke the members of the inner class through the main method.

  Anonymous internal class interview questions:
  According to the requirements, the code
  Interface Inter {void Show ();
  Class Outer {//Padded code}
  Class Outerdemo {
  public static void Main (string[] args) {
  Outer.method (). Show ();
  }
  }
  Required to output "HelloWorld" on the console

• */
  Interface inter3{
  void Show ();//public abstract
  }
  Class outer7{
  The code is padded
  public static Inter3 method () {

  //返回的是接口:当前并不提供接口的子实现类,所以只能用匿名内部类return new Inter3() {    public void show() {        System.out.println("helloworld");    }};

  }
  }
  Test class
  public class Test {

  public static void Main (string[] args) {

  Outer7.method().show();

  }
  }

Java Basic (four) face question