Object-Oriented Foundation--construction method and anonymous object

What is a construction method? A constructor method is called whenever an object is instantiated.
The following points should be noted in the construction method:-The name of the construction method must be the same as the class name-the declaration of a constructor method cannot have any declaration of the return value type-You cannot use return in the constructor method to return a value.

Class Person{public person () {//Declares the constructor method System.out.println ("A new person object is generated. ") ;}}; public class Consdemo01{public static void Main (String args[]) {System.out.println ("declared object: person per = null;"); person per = NULL;//The object is declared without invoking the constructor method System.out.println ("instantiated object: per = new person ();");p er = new Person ();//Instantiate Object}};

Sometimes when writing a class does not define the construction method, can also be executed, in fact, this is a Java operation mechanism, in the entire Java operation, if a class does not explicitly declare a construction method, it will automatically generate a non-parameter of what does not do anything do not do any of the paparazzi for the user to use. Similar to the following form.

Note: If you provide a constructor method for a class, you will no longer generate a parameterless, no-action construction method. If there is an exception to the new person (), the additional constructor method is added with the addition of a parameterless, no-action constructor.
Anonymous object: Anonymous is no name, in Java if an object is used only once, it can be defined as an anonymous object. The so-called anonymous object is a reference to a stack less than a normal object. As shown below:

Class Person{private String name;p rivate int;p ublic person (String n,int a) {//Declares the constructor method, initializes This.setname (n) for the properties in the class; Setage (a);} public void SetName (String n) {name = n;} public void Setage (int a) {if (a>0&&a<150) {age = A;}} Public String GetName () {return name;} public int getage () {return age;} public void Tell () {System.out.println ("name:" + this.getname () + "; Age:" + this.getage ());}}; public class Nonamedemo01{public static void Main (String args[]) {New person ("Zhang San", +). Tell ();}};

Design analysis of the class:

Class Student{private string Stuno;p rivate string name;p rivate float math;p rivate float 中文版;p rivate float computer ;p ublic Student () {}public Student (String s,string n,float m,float e,float c) {This.setstuno (s); This.setname (n); This.setmath (m); This.setenglish (e); This.setcomputer (c); public void Setstuno (String s) {Stuno = s;} public void SetName (String n) {name = n;} public void Setmath (float m) {math = m;} public void Setenglish (float e) {中文版 = e;} public void Setcomputer (float c) {computer = C;} Public String Getstuno () {return stuno;} Public String GetName () {return name;} public float Getmath () {return math;} public float Getenglish () {return 中文版;} public float Getcomputer () {return computer;} public float sum () {//SUM operation return math + 中文版 + computer;} Public float avg () {//averaging return this.sum ()/3;} public float Max () {//For highest result float max = math;//math is highest score max = Max>computer?max:computer; max = Max>english?max:englis h; return Max;} public float min () {//For lowest score float min = Math;//mathematics is the highest grade min = min<computer?min:computer; min = min<english?min:english; return min;}}; public class Exampledemo01{public static void Main (String args[]) {Student stu = null;//declaration Object Stu = new Student ("MLDN-33", " Li Xinghua ", 95.0f,89.0f,96.0f); SYSTEM.OUT.PRINTLN ("Student number:" + Stu.getstuno ()); System.out.println ("Student Name:" + stu.getname ()); System.out.println ("Math score:" + Stu.getmath ()); System.out.println ("English score:" + stu.getenglish ()); System.out.println ("Highest score:" + Stu.max ()); System.out.println ("Lowest score:" + stu.min ());}};

Object-Oriented Foundation--construction method and anonymous object