JAVA 第十四章 带参数的方法

1:定义带参方法
  语法:
     <访问修饰符> 返回值类型 <方法名>(<参数类表>){
      //方法的主体
}

2:调试带参方法:
   语法:
      对象名.方法名(参数1,参数2,……,参数n)
3:调用方法时,需要注意两点:
      *先实例化对象,再调用方法.
      *实参的类型,数量,顺序都要与形参一一对应.
4:调用带参方法与调用无参方法的语法是相同的,但是在调用带参方法时必须传入实际的参数的值.
5:形参是在定义方法的时候对参数的称呼,实参是在调用方法时传递给方法的实际的值.
6:Java中提供包来管理类.声明包使用关键字package,导入包使用关键字import.

上机练习1:

package com.mm;

import java.util.*;

public class stu {
	String[] g = new String[5];

	public void fell(String name) {
		for (int i = 0; i < g.length; i++) {
			if (g[i] == null) {
				g[i] = name;
				break;
			}
		}

	}

	public void showstu() {
		for (int i = 0; i < g.length; i++) {
			if (g[i] != null) {
				System.out.println(g[i]);
			}
		}
	}

	public void  show(){
		boolean find = true;
		while (find) {
			System.out.println("请输入客户姓名:");
			Scanner input = new Scanner(System.in);
			String name = input.next();
			find = false;
		}
		System.out.println("**********************************");
		System.out.println("\t客户姓名列表");
		System.out.println("**********************************");
		for (int i = 0; i < g.length; i++) {
			System.out.println(g[i] + " ");
		}
		

	}
	
	public void showeet(String old, String newname, String[]g) {
			for (int i = 0; i < g.length; i++) {
				if(g[i].equals(old)){
					g[i]=newname;
				}
			}
			for (int i = 0; i < g.length; i++) {
				System.out.println(g[i]);
			}

	}

}

package com.mm;

import java.util.*;

public class ru1 {
	public static void main(String[] args) {
		ru ru = new ru();

		ru.showru();
		ru.show();

	}
}

 

上机练习2:

package com.mm;

public class til {
	int[] score=new int[5];
	public double age( int[] score){
		int s=0;
		double age=0.0;
		for(int i=0;i<score.length;i++){
			s+=score[i];
		}
		age=(double)s/score.length;
		return age;
	}
	
	
	public int max(int[] score){
		int max=score[0];
		for(int i=1;i<score.length;i++){
			if(max<score[i]){
				max=score[i];
			}
		}
		return max;
		
	}
	public int min(int[] score){
		int min=score[0];
		for(int i=1;i<score.length;i++){
			if(min>score[i]){
				min=score[i];
			}
		}
		return min;
	}
}
<pre class="java" name="code"> 

package com.mm;
import java.util.*;
public class til11 {
public static void main(String[] args) {
	til s=new til();
	int[] score=new int[5];
	Scanner input=new Scanner(System.in);
	System.out.println("请输入参赛者的成绩:");
	for(int i=0;i<5;i++){
		score[i]=input.nextInt();
	}
	double age=s.age(score);
	System.out.println("平均数:"+age);
	int max=s.max(score);
	System.out.println("最高成绩:"+max);
	int min=s.min(score);
	System.out.println("最低成绩:"+min);
}
}

上机练习3:
package com.kk;

public class Client {
	public String name;
	public int age;
	boolean card;
	public Client(String name, int age, boolean card) {
		this.name = name;
		this.age = age;
		this.card = card;
	}
	
	
}

<pre class="java" name="code">package com.kk;

public class ClientTest {
	public static void main(String[] args) {
		Client c1=new Client("王一", 30, false);
		Client c2=new  Client("贺强", 19, true);
		System.out.println("客户信息:");
		System.out.println(c1.name+"\t"+c1.age+"\t"+c1.card);
		System.out.println(c2.name+"\t"+c2.age+"\t"+c2.card);
	}
}

<pre class="java" name="code">上机练习5:
package com.kk;

import java.util.Scanner;

public class Accout {
	int money;

	public static void main(String[] args) {

		Scanner input = new Scanner(System.in);
		Accout person = new Accout();
		do {
			System.out.println("1.存款 2.取款 0.退出");
			System.out.println("请选择你需要办理的业务:");
			int a = input.nextInt();
			switch (a) {
			case 1:
				System.out.println("请输入您存款的金额:");
				person.money += input.nextInt();
				System.out.println("存款成功.");
				System.out.println("****当前余额为:" + person.money + "元****");
				break;
			case 2:
				System.out.println("请输入您取款的金额:");
				person.money -= input.nextInt();
				System.out.println("取款成功.");
				System.out.println("****当前余额为:" + person.money + "元****");
				break;
			case 0:
				System.out.println("谢谢使用!");
				return;
			}

		} while (true);
	}
}

课后简答题2:
package com.kk;

import java.util.Scanner;

public class youno {
public static void main(String[] args) {

	 Scanner input = new Scanner(System.in);
	  System.out.println("请选择运算:1.加法 2.减法 3.乘法 4.除法"); int choose =
	  input.nextInt(); System.out.println("请输入第一个数字:"); int
	  num=input.nextInt(); System.out.println("请输入第二个数字:"); int
	  num1=input.nextInt(); switch (choose) { case 1:
	  System.out.println("****运算结果为:"+(num+num1)); break; case 2:
	  System.out.println("****运算结果为:"+(num-num1)); break; case 3:
	  System.out.println("****运算结果为:"+(num*num1)); break; case 4:
	  System.out.println("****运算结果为:"+(num/num1)); break; }
}
}