《Java程序设计案例教程》考试卷B答案.doc
Java程序设计案例教程考试卷B答案（一）略（二）import java.util.Scanner;public class QuestionB2 public static void main(String args) Scanner sc = new Scanner(System.in);System.out.print("输入正方形的边长：");double side = sc.nextDouble();System.out.println("正方形的周长：" + 4 * side);System.out.println("正方形的面积：" + Math.pow(side, 2);（三）public class QuestionB3 public static void main(String args) int f1 = 1, f2 = 1;for(int i = 1;i <= 18;i+)System.out.print(f1 + "t" + f2 + "t");if(i % 2 = 0)System.out.println();f1 = f1 + f2;f2 = f2 + f1;（四）public abstract class Vehicle private String fuel;/燃料private double speed;/速度public String getFuel() return fuel;public void setFuel(String fuel) this.fuel = fuel;public double getSpeed() return speed;public void setSpeed(double speed) this.speed = speed;public abstract void run();（五）public class Automobile extends Vehicle private String brand;/品牌public String getBrand() return brand;public void setBrand(String brand) this.brand = brand;Overridepublic void run() System.out.println("在公路上行驶");（六）import java.util.Scanner;public class QuestionB6 public static void main(String args) Scanner sc = new Scanner(System.in);System.out.print("输入杨辉三角的级数：");int level = sc.nextInt();int y = new intlevel;/行数int i, j;for(i = 0;i < y.length;i+)yi = new inti + 1;/列数y00 = 1;/第一行第一列元素for(i = 1;i < y.length;i+)yi0 = 1;/从第二行开始所有第一列所有元素for(j = 1;j < yi.length - 1;j+)/从第三行开始yij = yi - 1j - 1 + yi - 1j;/第一列和对角线之外元素yiyi.length - 1 = 1;/从第二行开始所有对角线元素for(i = y.length - 1;i >= 0;i-)/输出for(j = 0;j < yi.length;j+)System.out.print(yij + " ");System.out.println();（七）public class QuestionB7 extends Thread public void run() tryfor(int i = 1;i <= 10;i+)System.out.println(int)(Math.random() * 100);sleep(500);catch(InterruptedException ie)ie.printStackTrace();public static void main(String args) QuestionB7 qb7 = new QuestionB7();qb7.start();（八）import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import java.util.Scanner;import mons.codec.digest.DigestUtils;/加密组件包public class QuestionB8 public static void main(String args) Scanner sc = new Scanner(System.in);System.out.print("请输入用户名：");String name = sc.next();System.out.print("请输入密码：");String password = sc.next();tryClass.forName("com.mysql.jdbc.Driver");catch(ClassNotFoundException ce)System.out.println(ce);tryConnection con = DriverManager.getConnection("jdbc:mysql:/localhost:3306/myShujiku", "root", "mysql");PreparedStatement ps = con.prepareStatement("select * from zhanghu where xm = ?");ps.setString(1, xm);ResultSet rs = ps.executeQuery();if(rs.next()if(DigestUtils.md5Hex(password).equals(rs.getString("mm")/用户密码摘要处理System.out.println("欢迎访问数据库！");elseSystem.out.println("密码不正确！");elseSystem.out.println("用户不存在！");rs.close();ps.close();con.close();catch(SQLException ce)System.out.println(ce);
