方法的参数传递机制：只能是值传递

package Collection;



public class ZhiCd {
	//此处如果不加静态static
	//Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
  //	Cannot make a static reference to the non-static method swap(int, int) from the type ZhiCd

	
	public static void swap(int a,int b)
	{
		int temp;
		temp = a;
		a=b;
		b=temp;
		System.out.println("swap:"+"a:"+a+"  "+"b:"+b);
				
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int a=9;
		int b=6;
		swap(a, b);
		System.out.println("a:"+a+"  "+"b:"+b);

	}

}

 

 

package Collection;

 class DataWrap
 {
	 int a;
	 int b;
 }
public class ReferenceTransferTest {
	/**
	 * @param dw
	 */
	public static void swap(DataWrap dw)
	{
		int temp;
		temp=dw.a;
		dw.a=dw.b;
		dw.b=temp;
		System.out.println("DataWrap方法"+dw.a+"  "+dw.b);
	}

	public static void main(String[] args) {
		DataWrap dw=new DataWrap();
//		DataWrap dw=null;
		dw.a=6;
		dw.b=9;
		swap(dw);
		System.out.println("DataWrap方法后"+dw.a+" "+dw.b);

	}

}

　　

 

递归方法：

例子：
f(0)=1,f(1)=4,f(n+2)=2*f(n+1)+f(n)

package Collection;
public class Recursive {
	public static int fn(int n)
	{
		if(n==0)
		{
			return 1;
		}
		else if(n==1)
		{
			return 4;
		}
		else {
			return 2*fn(n-1)+fn(n-2);
		}
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
    System.out.println(fn(10));
    //10497
	}

}

　　

setter和getter方法：

package Collection;

public class Person {
	//使用private修饰成员变量
	private String name;
	private int age;
	
	public String getName() {
		return name;
	}
	public void setName(String name) {
		//执行合理性校验，要求用户名必须在2-6位之间
		if(name.length()>6||name.length() <2)
		{
			System.out.println("您设置的人名不符合要求");
			return;
		}
		else 
		{
			this.name=name;
		}
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		//执行合理性校验，要求用户年龄必须在0-100
		if(age>100||age<0)
		{
			System.out.println("您输入的人名不正确");
			return;
		}
		else{
		this.age = age;
		}
	}
	


	

}

　　

super:

package Collection;

import java.util.Scanner;

class BaseClass
{
	public int  a=5;
}
public class SubClass extends BaseClass {
	public int a=7;
	
	public void accessOwner()
	{
		System.out.println(a);
	}
	public void bccessOwner()
	{
		//super限定只能从父类取得实例变量和方法
		System.out.println(super.a);
	}
			

	public static void main(String[] args) {
		// TODO Auto-generated method stub
          
	     SubClass subClass=new SubClass();
	     subClass.accessOwner();
	     subClass.bccessOwner();
		
		 
	}

}