Java变量的初始化以及静态方法

 1 package treat;
 2 class InitializeBlockClass
 3 {
 4     public int field=100;
 5     {
 6         field=200;
 7     }
 8     public InitializeBlockClass(int value)
 9     {
10         this.field=value;
11     }
12     public InitializeBlockClass()
13     {
14         
15     }
16 }
17 
18 public class treat {
19     public static void main(String args[])
20     {
21         InitializeBlockClass obj=new InitializeBlockClass();
22         System.out.println(obj.field);
23         obj=new InitializeBlockClass(300);
24         System.out.println(obj.field);
25     }
26 }

 1 package treat;
 2 
 3 public class treat {
 4     
 5     public int dg=0;
 6     void fun()
 7     {
 8         System.out.println("hello world!!");
 9     }
10     static void play(treat a)//通过形参传递对象实现非静态方法的调用
11     {
12         a.fun();
13         a.dg=8;//调用对象改变非静态字段的值
14         System.out.println(a.dg);
15     }
16     public static void main(String args[])
17     {
18         treat a=new treat();
19         treat.play(a);
20     }
21 }