创建一个简单版本的银行 Account 类
创建一个简单版本的 Account 类。将这个源文件放入 banking 程序包中。在创建单个帐户的默认程序包中,编写一个测试程序 TestBanking。这个测试程序初始化帐户余额,并可执行几种简单的事务处理。最后,该测试程 序显示该帐户的最终余额
package banking;
// 在 banking 包下创建 Account 类
public class Account {
private double balance;
//带有一个参数(init_balance)的公有构造器
public Account(double init_balance){
System.out.println("Creating an account with a "+init_balance+" balance");
balance=init_balance;
}
//该方法用于获取余额
public double geBalance(){
return balance;
}
//该方法向当前余额增加金额
public void deposit(double amt){
System.out.println("deposit "+amt);
balance=balance+amt;
}
//从当前余额中减去金额
public void withdraw(double amt){
System.out.println("deposit "+amt);
balance=balance-amt;
}
}
package test;
import banking.Account;
public class TestBanking {
public static void main(String[] args) {
Account p1= new Account(500);
p1.withdraw(150);
p1.deposit(22.5);
p1.withdraw(47.62);
System.out.println("The account has a balance of "+p1.geBalance());
}
}
圆柱体的底面积和高
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
float R,H;
Scanner reader = new Scanner(System.in);
Column Column=new Column();
System.out.println("plaese input R:");
R=reader.nextFloat();
System.out.println("plaese input H:");
H=reader.nextFloat();
Column.S(R);
Column.V(R, H);
}
}
public class Column {
double pi=java.lang.Math.PI;
public double S(float R) {
System.out.println("s="+pi*R*R);
return pi*R*R;
}
public double V(float R,float H) {
System.out.println("v="+pi*R*R*H);
return pi*R*R*H;
}
}