1 package cn.lyhh; 2 class Person{ 3 private String name; 4 private int age; 5 static String city = "A城"; 6 public Person(String name,int age) { 7 this.name = name; 8 this.age = age; 9 } 10 public String getInfo() { 11 return "姓名:" + this.name + ",年龄:" + this.age + ",城市:" + city; 12 } 13 } 14 public class L { 15 public static void main(String[] args) { 16 Person per1 = new Person("张三",30); 17 Person per2 = new Person("李四",31); 18 Person per3 = new Person("王五",30); 19 System.out.println("======修改信息之前======"); 20 System.out.println(per1.getInfo()); 21 System.out.println(per2.getInfo()); 22 System.out.println(per3.getInfo()); 23 System.out.println("======修改信息之后======"); 24 Person.city = "B城"; 25 System.out.println(per1.getInfo()); 26 System.out.println(per2.getInfo()); 27 System.out.println(per3.getInfo()); 28 29 } 30 } 31 32 33 34 35 36 package cn.lyhh; 37 class La{ 38 private static La instance = new La(); 39 private La() { 40 } 41 public static La getInstance() { 42 return instance; 43 } 44 public void print() { 45 System.out.println("hello world!!!"); 46 } 47 } 48 public class L { 49 public static void main(String[] args) { 50 La s = null; 51 s = La.getInstance(); 52 s.print(); 53 } 54 55 } 56 57 58 59 package cn.mxl; 60 class Person{ 61 private String name; 62 private static int count; 63 public Person() { 64 count++; 65 this.name = "NONAME - " + count; 66 } 67 public Person(String name) { 68 this.name = name; 69 } 70 public String getInfo() { 71 return "姓名:" + this.name; 72 } 73 } 74 public class Ly{ 75 public static void main(String[] args) { 76 System.out.println(new Person().getInfo()); 77 System.out.println(new Person("A").getInfo()); 78 System.out.println(new Person("B").getInfo()); 79 System.out.println(new Person().getInfo()); 80 } 81 82 } 83 84 85 86 87 88 package cn.mxl; 89 class Person{ 90 private String name; 91 private static int count; 92 public Person() { 93 count++; 94 System.out.println("产生了" + count + "个实例化"); 95 } 96 public String getInfo() { 97 return "姓名:" + this.name; 98 } 99 } 100 public class Y { 101 public static void main(String[] args) { 102 new Person(); 103 new Person(); 104 new Person(); 105 new Person(); 106 new Person(); 107 } 108 } 109 110 111 112 package cn.lyh; 113 114 public class MXL { 115 public static void main(String[] args) { 116 for (int x=0;x<args.length;x++) { 117 System.out.println(args[x] + "、"); 118 } 119 } 120 }