小峰视频十五：方法

一、基本的方法调用

public class Person {
	//无参
	void speak(){
		System.out.println("我是袁隆盛！！");
	}
	
	//带参
	void speak(String name){
		System.out.println("我是"+name);
	}
	
	//多个参数
	void speak(String name,int age){
		System.out.println("我是"+name+",我今年"+age+"岁!	");
	}
	
	//不固定参数
	void speak(String name,int age,String ...hobbies){
		System.out.println("我是"+name+",我今年"+age+"岁!	");
		for (String hobby : hobbies) {
			System.out.print(hobby+" ");
		}
	}
	
	//有返回值
	int speak01(String name,int age,String ...hobbies){
		System.out.println("我是"+name+",我今年"+age+"岁!	");
		for (String hobby : hobbies) {
			System.out.print(hobby+" ");
		}
		return hobbies.length;
	}
	
	public static void main(String[] args) {
		Person p = new Person();
		p.speak();
		p.speak("袁隆盛");
		p.speak("袁隆盛", 25);
		p.speak("袁隆盛", 25, "乒乓球","唱歌","编程");
		int n = p.speak01("袁隆盛", 25, "乒乓球","唱歌","编程");
		System.out.println("我有"+n+"个爱好");
	}
}

　　二、参数的传递

public class Person02 {
	
	void speak(int age){
		System.out.println("我今年"+age+"!");
		age = 24;
		System.out.println(age);//输出24
	}
	
	public static void main(String[] args) {
		Person02 p2 = new Person02();
		int age = 23;
		p2.speak(age);
		System.out.println(age);//输出23，方法里面的变动不影响外侧的结果
	}

}

　　

class Sanwei{
	int xiongwei;
	int tunwei;
	int jianwei;
}

public class Person03 {
	
	void speak(Sanwei sanwei){
		sanwei.xiongwei = 20;
		sanwei.tunwei = 20;
		sanwei.jianwei = 20;
		System.out.println("我的三围是："+sanwei.xiongwei+" "+sanwei.tunwei+" "+sanwei.jianwei);//输出20
	}
	
	public static void main(String[] args) {
		Sanwei sanwei = new Sanwei();
		sanwei.xiongwei = 30;
		sanwei.tunwei = 30;
		sanwei.jianwei = 30;
		Person03 p = new Person03();
		System.out.println("我的三围是："+sanwei.xiongwei+" "+sanwei.tunwei+" "+sanwei.jianwei);//输出30
		p.speak(sanwei);
	}

}

　　

public class Person {//无参void speak(){System.out.println("我是袁隆盛！！");}//带参void speak(String name){System.out.println("我是"+name);}//多个参数void speak(String name,int age){System.out.println("我是"+name+",我今年"+age+"岁!");}//不固定参数void speak(String name,int age,String ...hobbies){System.out.println("我是"+name+",我今年"+age+"岁!");for (String hobby : hobbies) {System.out.print(hobby+" ");}}//有返回值int speak01(String name,int age,String ...hobbies){System.out.println("我是"+name+",我今年"+age+"岁!");for (String hobby : hobbies) {System.out.print(hobby+" ");}return hobbies.length;}public static void main(String[] args) {Person p = new Person();p.speak();p.speak("袁隆盛");p.speak("袁隆盛", 25);p.speak("袁隆盛", 25, "乒乓球","唱歌","编程");int n = p.speak01("袁隆盛", 25, "乒乓球","唱歌","编程");System.out.println("我有"+n+"个爱好");}}