• 201771010135 杨蓉庆AND张燕 《面对对象程序设计(java)》第十一周学习总结


    1、实验目的与要求

    (1) 掌握Vetor、Stack、Hashtable三个类的用途及常用API;

    (2) 了解java集合框架体系组成;

    (3) 掌握ArrayList、LinkList两个类的用途及常用API。

    (4) 了解HashSet类、TreeSet类的用途及常用API。

    (5)了解HashMap、TreeMap两个类的用途及常用API;

    (6) 结对编程(Pair programming练习,体验程序开发中的两人合作

    一、理论知识

    1、数据结构介绍

     (1)一般将数据结构分为两大类:线性数据结构和 非线性数据结构。

     (2)线性数据结构:线性表、栈、队列、串、数组 和文件。

    (3)线性表按其存储结构可分为顺序表和链表, 用顺序存储结构存储的线性表称为顺序表;

    (4)栈(Stack)也是一种特殊的 线性表,是一种后进先出 (LIFO)的结构。

    (5)队列(Queue)是限定所有的插入只能在表的一端进行 ,而所有的删除都在表的另一端进行的线性表。

    (6)散列表又称为哈希表;

    (7)负载因子越高 (越接近1.0),内存的使用效率越高,元素的 寻找时间越长。负载因子越低 (越接近0.0),元素的寻找时 间越短,内存浪费越多。

    2、JAVA的集合框架

    (1)集合(Collection或称为容器 )是一种包含多个元素 并提供对所包含元素操作方法的类,其包含的元 素可以由同一类型的对象组成,也可以由不同类 型的对象组成。

    (2)框架就是一个类库的集合,框架中包含很多 超类,编程者创建这些超类的子类可较方便的设 计设计程序所需的类。例如:Swing类包

    (3)集合类的作用: Java的集合类提供了一些基本数据结构的支持。 – 例如Vector;

    (4)集合类的使用: Java的集合类包含在java.util包中。

    (5)集合类的特点:特点一:  只容纳对象。

                                     特点二:集合类容纳的对象都是Object类的实例,一旦把一个对象置入集合类中,它的类信息将丢失;

    3、JDK1.1版本中的集合类

    (1)Vector中只能存放对象。

        Vector的元素通过下标进行访问。

        Vector类关键属性: capacity表示集合最多能容纳的元素个数。capacityIncrement表示每次增加多少容量。size表示集合当前元素个数。

    (2)Vector类的关键方法: void addElement(Object obj)     void add(int index, Object element)      Object elementAt(int index)

    (3)Stack类是Vector的子类。

        Stack类描述堆栈数据结构,即LIFO。

    (4)Hashtable类 :Hashtable通过键来查找元素。

        Hashtable用散列码(hashcode)来确定键。所有对象都有一个散列码,可以通过Object类的 hashCode()方法获得。

    2、实验内容和步骤

    实验1: 导入第9章示例程序,测试程序并进行代码注释。

    测试程序1:

    l 使用JDK命令运行编辑、运行以下三个示例程序,结合运行结果理解程序;

    掌握Vetor、Stack、Hashtable三个类的用途及常用API。

    import java.util.Vector;
    
    //示例程序1
    
    class Cat {
        private int catNumber;
    
        Cat(int i) {
            catNumber = i;
        }
    
        void print() {
            System.out.println("Cat #" + catNumber);
        }
    }
    class Dog {
        private int dogNumber;
    
        Dog(int i) {
            dogNumber = i;
        }
    
        void print() {
            System.out.println("Dog #" + dogNumber);
        }
    }
    public class CatsAndDogs {
        public static void main(String[] args) {
            Vector cats = new Vector();//创建一个新的类
            for (int i = 0; i < 7; i++)
                cats.addElement(new Cat(i));
            cats.addElement(new Dog(7));
            for (int i = 0; i < cats.size(); i++)
            if(cats.elementAt(i)instanceof Cat)// instanceof运算符是用来指出对象是否是特定类的一个实例
            {    
                ((Cat) cats.elementAt(i)).print();
            }else {
                ((Dog) cats.elementAt(i)).print();
            }
        }}

    结果如下:

    示例2:

    //示例程序2
    import java.util.*;
    
    public class Stacks {
        static String[] months = { "1", "2", "3", "4" };
    
        public static void main(String[] args) {
            Stack stk = new Stack();
            for (int i = 0; i < months.length; i++)
                stk.push(months[i]);//放入一个i值
            System.out.println(stk);
            System.out.println("element 2=" + stk.elementAt(2));//element表示一个节点
            while (!stk.empty())
                System.out.println(stk.pop());//出栈操作
        }
    }
    Stacks

    结果如下:

    示例3:

    import java.util.*;
    
    class Counter {
        int i = 1;
        public String toString() {
            return Integer.toString(i);
        }
        }
    public class Statistics {
        public static void main(String[] args) {
            Hashtable ht = new Hashtable();//生成集合类Hashtable
            for (int i = 0; i < 10000; i++) //生成循环体
            {
                Integer r = new Integer((int) (Math.random() * 20));//随机生成实数定义为整型
                if (ht.containsKey(r))
                    ((Counter) ht.get(r)).i++;//用来判断r是否为一个间值
                else
                    ht.put(r, new Counter());//创建新的Counter对象
            }
            System.out.println(ht);
        }
    }

    结果如下:

    测试程序2:

    l 使用JDK命令编辑运行ArrayListDemo和LinkedListDemo两个程序,结合程序运行结果理解程序;

    import java.util.*;
    
    public class ArrayListDemo {
        public static void main(String[] argv) {
            ArrayList al = new ArrayList();
            //用Add来添加对象且可以重载
            // Add lots of elements to the ArrayList...
            al.add(new Integer(11));
            al.add(new Integer(12));
            al.add(new Integer(13));
            al.add(new String("hello"));
            System.out.println(al.size());//输出al的长度
            // First print them out using a for loop.
            System.out.println("Retrieving by index:");
            for (int i = 0; i < al.size(); i++) {
                System.out.println("Element " + i + " = " + al.get(i));
            }
        }
    }
    ArrayListDemo

    结果如下:

    mport java.util.*;
    public class LinkedListDemo {
        public static void main(String[] argv) {
            LinkedList l = new LinkedList();
            l.add(new Object());
            l.add("Hello");
            l.add("zhangsan");//add方法可以重载
           
            ListIterator li = l.listIterator(0);//迭代器生成li对象
            while (li.hasNext())//hasNext方法用来返回迭代器的对象
                System.out.println(li.next());
            if (l.indexOf("Hello") < 0) //生成循环语句判断最后结果 
                System.err.println("Lookup does not work");
            else
                System.err.println("Lookup works");
       }
    }
    LinkedListDemo

    结果如下:

     

    测试程序3:

    l 运行SetDemo程序,结合运行结果理解程序;

    import java.util.*;
    public class SetDemo {
        public static void main(String[] argv) {
            HashSet h = new HashSet(); //也可以 Set h=new HashSet()
            h.add("One");
            h.add("Two");
            h.add("One"); // DUPLICATE
            h.add("Three");
            Iterator it = h.iterator();
            while (it.hasNext()) //hasNext方法
            {
                 System.out.println(it.next());
            }
        }
    }
    SetDemo

    结果如下:

    •  Elipse环境下调试教材365页程序9-2,结合运行结果理解程序;了解HashSet类的用途及常用API
    package set;
    
    
    import java.util.*;
    
    /**
     * This program uses a set to print all unique words in System.in.
     * @version 1.12 2015-06-21
     * @author Cay Horstmann
     */
    public class SetTest
    {
       public static void main(String[] args)
       {
           
          Set<String> words = new HashSet<>(); // HashSet implements Set
          long totalTime = 0;
          
          try (Scanner in = new Scanner(System.in))
          {
             while (in.hasNext())//迭代器的用法,判断当前元素是否存在
             {
                String word = in.next();//指向下一个元素
                long callTime = System.currentTimeMillis();
                words.add(word);//
                callTime = System.currentTimeMillis() - callTime;
                totalTime += callTime;
             }
          }
    
          Iterator<String> iter = words.iterator();//迭代器的简单实现
          for (int i = 1; i <= 20 && iter.hasNext(); i++)
             System.out.println(iter.next());
          System.out.println(". . .");
          System.out.println(words.size() + " distinct words. " + totalTime + " milliseconds.");
       }
    }

    小结:HashSet类中存放的对象不能重复,不能保证元素的排列顺序,顺序有可能发生变化。

    Elipse环境下调试教材367-368程序9-39-4,结合程序运行结果理解程序;了解TreeSet类的用途及常用API

    package treeSet;
    
    import java.util.*;
    
    /**
     * This program sorts a set of item by comparing their descriptions.
     * @version 1.12 2015-06-21
     * @author Cay Horstmann
     */
    public class TreeSetTest
    {
       public static void main(String[] args)
       {
          SortedSet<Item> parts = new TreeSet<>();
          parts.add(new Item("Toaster", 1234));//add方法
          parts.add(new Item("Widget", 4562));
          parts.add(new Item("Modem", 9912));
          System.out.println(parts);
    
          NavigableSet<Item> sortByDescription = new TreeSet<>(
                Comparator.comparing(Item::getDescription));
    
          sortByDescription.addAll(parts);
          System.out.println(sortByDescription);
       }
    }
    TreeSetTest
    package treeSet;
    
    import java.util.*;
    
    /**
     * An item with a description and a part number.
     */
    public class Item implements Comparable<Item>//Item类实现Comparable接口
    {
       private String description;
       private int partNumber;
    
       /**
        * Constructs an item.
        * 
        * @param aDescription
        *           the item's description
        * @param aPartNumber
        *           the item's part number
        */
       public Item(String aDescription, int aPartNumber)
       {
          description = aDescription;//字符串
          partNumber = aPartNumber;
       }
    
       /**
        * Gets the description of this item.
        * 
        * @return the description
        */
       public String getDescription()
       {
          return description;
       }
    
       public String toString()
       {
          return "[description=" + description + ", partNumber=" + partNumber + "]";
       }//返回该对象的字符串表示
    
       public boolean equals(Object otherObject)
       {
          if (this == otherObject) return true;
          if (otherObject == null) return false;
          if (getClass() != otherObject.getClass()) return false;
          Item other = (Item) otherObject;
          return Objects.equals(description, other.description) && partNumber == other.partNumber;
       }
    
       public int hashCode()
       {
          return Objects.hash(description, partNumber);
       }
    
       public int compareTo(Item other)
       {
          int diff = Integer.compare(partNumber, other.partNumber);
          return diff != 0 ? diff : description.compareTo(other.description);
       }
    }
    Item

    结果如下:

    小结:TreeSet是一种自带排序的set,TreeSet可以确保集合元素处于排序状态。TreeSet支持两种排序方式,自然排序 和定制排序。

    测试程序4:

    使用JDK命令运行HashMapDemo程序,结合程序运行结果理解程序;

    import java.util.*;
    public class HashMapDemo {
       public static void main(String[] argv) {
          HashMap h = new HashMap();
          // The hash maps from company name to address.
          h.put("Adobe", "Mountain View, CA");//定义对象
          h.put("IBM", "White Plains, NY");
          h.put("Sun", "Mountain View, CA");
          String queryString = "Adobe";
          String resultString = (String)h.get(queryString);
          System.out.println("They are located in: " +  resultString);
      }
    }

    结果如下:

    l 在Elipse环境下调试教材373页程序9-6,结合程序运行结果理解程序;

    package map;
    
    import java.util.*;
    
    /**
     * This program demonstrates the use of a map with key type String and value type Employee.
     * @version 1.12 2015-06-21
     * @author Cay Horstmann
     */
    public class MapTest
    {
       public static void main(String[] args)
       {
          Map<String, Employee> staff = new HashMap<>();//HashMap implements Map
          staff.put("144-25-5464", new Employee("Amy Lee"));
          staff.put("567-24-2546", new Employee("Harry Hacker"));
          staff.put("157-62-7935", new Employee("Gary Cooper"));
          staff.put("456-62-5527", new Employee("Francesca Cruz"));
    
          // print all entries
    
          System.out.println(staff);
    
          // remove an entry
    
          staff.remove("567-24-2546");
    
          // replace an entry
    
          staff.put("456-62-5527", new Employee("Francesca Miller"));
    
          // look up a value
    
          System.out.println(staff.get("157-62-7935"));
    
          // iterate through all entries
    
          staff.forEach((k, v) -> 
             System.out.println("key=" + k + ", value=" + v));
       }
    }

    结果如下:

    实验2:结对编程练习:

    关于结对编程:以下图片是一个结对编程场景:两位学习伙伴坐在一起,面对着同一台显示器,使用着同一键盘,同一个鼠标,他们一起思考问题,一起分析问题,一起编写程序

    关于结对编程的阐述可参见以下链接:

     http://www.cnblogs.com/xinz/archive/2011/08/07/2130332.html

    http://en.wikipedia.org/wiki/Pair_programming

    对于结对编程中代码设计规范的要求参考

    http://www.cnblogs.com/xinz/archive/2011/11/20/2255971.html

    以下实验,就让我们来体验一下结对编程的魅力

    确定本次实验结对编程合作伙伴;

    各自运行合作伙伴实验九编程练习1,结合使用体验对所运行程序提出完善建议;

    l 各自运行合作伙伴实验十编程练习2,结合使用体验对所运行程序提出完善建议;

    1、合作伙伴:张燕

    • 采用结对编程方式,与学习伙伴合作完成实验九编程练习1; 
    package xinxi;
    
    import java.io.BufferedReader;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.Collections;
    import java.util.Scanner;
    
    public class xinxi{
        private static ArrayList<Student> studentlist;
        public static void main(String[] args) {
            studentlist = new ArrayList<>();
            Scanner scanner = new Scanner(System.in);
            File file = new File("F:\身份证号.txt");
            try {
                FileInputStream fis = new FileInputStream(file);
                BufferedReader in = new BufferedReader(new InputStreamReader(fis));
                String temp = null;
                while ((temp = in.readLine()) != null) {
                    
                    Scanner linescanner = new Scanner(temp);
                    
                    linescanner.useDelimiter(" ");    
                    String name = linescanner.next();
                    String number = linescanner.next();
                    String sex = linescanner.next();
                    String age = linescanner.next();
                    String province =linescanner.nextLine();
                    Student student = new Student();
                    student.setName(name);
                    student.setnumber(number);
                    student.setsex(sex);
                    int a = Integer.parseInt(age);
                    student.setage(a);
                    student.setprovince(province);
                    studentlist.add(student);
    
                }
            } catch (FileNotFoundException e) {
                System.out.println("学生信息文件找不到");
                e.printStackTrace();
            } catch (IOException e) {
                System.out.println("学生信息文件读取错误");
                e.printStackTrace();
            }
            boolean isTrue = true;
            while (isTrue) {
                System.out.println("输入序号进行相应的操作");
                System.out.println("1.字典排序");
                System.out.println("2.输出年龄最大和年龄最小的人");
                System.out.println("3.查找与你年龄相近的人");
                System.out.println("4.查找你的同乡");
                String n = scanner.next();
                switch (n) {
                case "1":
                    Collections.sort(studentlist);              
                    System.out.println(studentlist.toString());
                    break;
                case "2":
                     int max=0,min=100;
                     int j,k1 = 0,k2=0;
                     for(int i=1;i<studentlist.size();i++)
                     {
                         j=studentlist.get(i).getage();
                     if(j>max)
                     {
                         max=j; 
                         k1=i;
                     }
                     if(j<min)
                     {
                       min=j; 
                       k2=i;
                     }
                     
                     }  
                     System.out.println("年龄最大:"+studentlist.get(k1));
                     System.out.println("年龄最小:"+studentlist.get(k2));
                    break;
                case "3":
                    System.out.println("年龄:");
                    int yourage = scanner.nextInt();
                    int near=agenear(yourage);
                    int value=yourage-studentlist.get(near).getage();
                    System.out.println("和你年龄相近的是"+studentlist.get(near));
                    break;
    
                case "4":
                     System.out.println("输入你的家乡");
                     String find = scanner.next();        
                     String place=find.substring(0,3);
                     for (int i = 0; i <studentlist.size(); i++) 
                     {
                         if(studentlist.get(i).getprovince().substring(1,4).equals(place)) 
                             System.out.println("你的同乡是  "+studentlist.get(i));
                     }             
                     break;
    
                }
            }
        }
            public static int agenear(int age) {      
            int j=0,min=53,value=0,k=0;
             for (int i = 0; i < studentlist.size(); i++)
             {
                 value=studentlist.get(i).getage()-age;
                 if(value<0) value=-value; 
                 if (value<min) 
                 {
                    min=value;
                    k=i;
                 } 
              }    
             return k;         
          
    
    }
    
    
    }
    xinxi
    package xinxi;
    public class Student implements Comparable<Student> {
    
        private String name;
        private String number ;
        private String sex ;
        private int age;
        private String province;
       
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public String getnumber() {
            return number;
        }
        public void setnumber(String number) {
            this.number = number;
        }
        public String getsex() {
            return sex ;
        }
        public void setsex(String sex ) {
            this.sex =sex ;
        }
        public int getage() {
    
            return age;
            }
        public void setage(int age) {
            this.age= age;
            }
    
        public String getprovince() {
            return province;
        }
        public void setprovince(String province) {
            this.province=province ;
        }
    
        public int compareTo(Student o) {
           return this.name.compareTo(o.getName());
        }
    
        public String toString() {
            return  name+"	"+sex+"	"+age+"	"+number+"	"+province+"
    ";
        }    
    }
    class

    心得:通过测试,可以体会到小伙伴的代码与我的不同之处,需要学习的还很多。

    • 采用结对编程方式,与学习伙伴合作完成实验十编程练习2。
    package S;
    
    
    import java.io.*;
    import java.io.PrintWriter;
    import java.util.Scanner;
    
    public class jisuan {
        public static void main(String[] args) {
    
            Scanner in = new Scanner(System.in);
    
            PrintWriter output = null;
            try {
                output = new PrintWriter("text.txt");
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            int sum = 0;
            for (int i = 1; i <= 10; i++) {
                int a = (int) Math.round(Math.random() * 100);
                int b = (int) Math.round(Math.random() * 100);
                int m = (int) Math.round(Math.random() * 4);
                switch (m) {
                case 1:
                    while (b == 0) {
                        b = (int) Math.round(Math.random() * 100);
                    }
                    while (a % b != 0) {
                        a = (int) Math.round(Math.random() * 100);
                    }
                    System.out.println(a + "/" + b + "=");
                    int c1 = in.nextInt();
                    output.println(a + "/" + b + "=" + c1);
                    if (c1 == a / b) {
                        System.out.println("恭喜答案正确");
                        sum += 10;
                    } else {
                        System.out.println("抱歉,答案错误");
                    }
    
                    break;
    
                case 2:
                    System.out.println( a + "*" + b + "=");
                    int c2 = in.nextInt();
                    output.println(a + "*" + b + "=" + c2);
                    if (c2 == a * b) {
                        System.out.println("恭喜答案正确");
                        sum += 10;
                    } else {
                        System.out.println("抱歉,答案错误");
                    }
                    break;
                case 3:
                    System.out.println( a + "+" + b + "=");
                    int c3 = in.nextInt();
                    output.println(a + "+" + b + "=" + c3);
                    if (c3 == a + b) {
                        System.out.println("恭喜答案正确");
                        sum += 10;
                    } else {
                        System.out.println("抱歉,答案错误");
                    }
    
                    break;
                case 4:
                    while (a < b) {
                        a = (int) Math.round(Math.random() * 100);
                    }
                    System.out.println( a + "-" + b + "=");
                    int c4 = in.nextInt();
                    output.println(a + "-" + b + "=" + c4);
                    if (c4 == a - b) {
                        System.out.println("恭喜答案正确");
                        sum += 10;
                    } else {
                        System.out.println("抱歉,答案错误");
                    }
                    break;
    
                }
    
            }
            System.out.println("成绩" + sum);
            output.println("成绩" + sum);
            output.close();
        }
    }
    jisuan
    package S;
    public class math<T> {
        private T a;
        private T b;
    
        public int add(int a, int b) {
            return a + b;
        }
    
        public int reduce(int a, int b) {
            return a - b;
        }
    
        public int multiplication(int a, int b) {
            return a * b;
        }
    
        public int division(int a, int b) {
            if (b != 0 && a % b == 0)
                return a / b;
            else
                return 0;
        }
    }
    math

    心得:合作小伙伴代码写的很多很详细,我从中学到了很多知识,如果可以的话,可以在代码的精简上多做些功夫。

    2)    结对编程代码;

    实验九编程练习1:

    package xinxi;
    
    import java.io.BufferedReader;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.Collections;
    import java.util.Scanner;
    
    public class xinxi{
        private static ArrayList<Student> studentlist;
        public static void main(String[] args) {
            studentlist = new ArrayList<>();
            Scanner scanner = new Scanner(System.in);
            File file = new File("F:\身份证号.txt");
            try {
                FileInputStream fis = new FileInputStream(file);
                BufferedReader in = new BufferedReader(new InputStreamReader(fis));
                String temp = null;
                while ((temp = in.readLine()) != null) {
                    
                    Scanner linescanner = new Scanner(temp);
                    
                    linescanner.useDelimiter(" ");    
                    String name = linescanner.next();
                    String number = linescanner.next();
                    String sex = linescanner.next();
                    String age = linescanner.next();
                    String province =linescanner.nextLine();
                    Student student = new Student();
                    student.setName(name);
                    student.setnumber(number);
                    student.setsex(sex);
                    int a = Integer.parseInt(age);
                    student.setage(a);
                    student.setprovince(province);
                    studentlist.add(student);
    
                }
            } catch (FileNotFoundException e) {
                System.out.println("学生信息文件找不到");
                e.printStackTrace();
            } catch (IOException e) {
                System.out.println("学生信息文件读取错误");
                e.printStackTrace();
            }
            boolean isTrue = true;
            while (isTrue) {
                System.out.println("输入序号进行相应的操作");
                System.out.println("1.字典排序");
                System.out.println("2.输出年龄最大和年龄最小的人");
                System.out.println("3.查找与你年龄相近的人");
                System.out.println("4.查找你的同乡");
                String n = scanner.next();
                switch (n) {
                case "1":
                    Collections.sort(studentlist);              
                    System.out.println(studentlist.toString());
                    break;
                case "2":
                     int max=0,min=100;
                     int j,k1 = 0,k2=0;
                     for(int i=1;i<studentlist.size();i++)
                     {
                         j=studentlist.get(i).getage();
                     if(j>max)
                     {
                         max=j; 
                         k1=i;
                     }
                     if(j<min)
                     {
                       min=j; 
                       k2=i;
                     }
                     
                     }  
                     System.out.println("年龄最大:"+studentlist.get(k1));
                     System.out.println("年龄最小:"+studentlist.get(k2));
                    break;
                case "3":
                    System.out.println("年龄:");
                    int yourage = scanner.nextInt();
                    int near=agenear(yourage);
                    int value=yourage-studentlist.get(near).getage();
                    System.out.println("和你年龄相近的是"+studentlist.get(near));
                    break;
    
                case "4":
                     System.out.println("输入你的家乡");
                     String find = scanner.next();        
                     String place=find.substring(0,3);
                     for (int i = 0; i <studentlist.size(); i++) 
                     {
                         if(studentlist.get(i).getprovince().substring(1,4).equals(place)) 
                             System.out.println("你的同乡是  "+studentlist.get(i));
                     }             
                     break;
    
                }
            }
        }
            public static int agenear(int age) {      
            int j=0,min=53,value=0,k=0;
             for (int i = 0; i < studentlist.size(); i++)
             {
                 value=studentlist.get(i).getage()-age;
                 if(value<0) value=-value; 
                 if (value<min) 
                 {
                    min=value;
                    k=i;
                 } 
              }    
             return k;         
          
    
    }
    
    
    }
    xinxi
    package xinxi;
    public class Student implements Comparable<Student> {
    
        private String name;
        private String number ;
        private String sex ;
        private int age;
        private String province;
       
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public String getnumber() {
            return number;
        }
        public void setnumber(String number) {
            this.number = number;
        }
        public String getsex() {
            return sex ;
        }
        public void setsex(String sex ) {
            this.sex =sex ;
        }
        public int getage() {
    
            return age;
            }
        public void setage(int age) {
            this.age= age;
            }
    
        public String getprovince() {
            return province;
        }
        public void setprovince(String province) {
            this.province=province ;
        }
    
        public int compareTo(Student o) {
           return this.name.compareTo(o.getName());
        }
    
        public String toString() {
            return  name+"	"+sex+"	"+age+"	"+number+"	"+province+"
    ";
        }    
    }
    Student

    实验十编程练习2:

    package C;
    
    import java.io.FileNotFoundException;
    import java.io.PrintWriter;
    import java.util.Random;
    import java.util.Scanner;
    
    public class Main {
        public static void main(String[] args) {
            Scanner in = new Scanner(System.in);
            Suanfa counter = new Suanfa();
            PrintWriter out = null;
            try {
                out = new PrintWriter("test.txt");
            } catch (FileNotFoundException e) {
                System.out.println("文件夹输出失败");
                e.printStackTrace();
            }
    
            int sum = 0;
            
            for (int i = 1; i <= 10; i++) {
                int a = (int) Math.round(Math.random() * 100);
                int b = (int) Math.round(Math.random() * 100);
                int m;
                Random rand = new Random();
                m = (int) rand.nextInt(4) + 1;
                System.out.println("随机生成的四则运算类型:" + m);
    
                switch (m) {
                case 1:
                    a = b + (int) Math.round(Math.random() * 100);
                    while(b == 0){
                        b = (int) Math.round(Math.random() * 100);
                    }
                    while(a % b != 0){
                        a = (int) Math.round(Math.random() * 100);
                        }
                  //若生成的除法式子必须能整除,且满足分母为0的条件,则a一定要大于b,且a模b的结果要为0。
                    System.out.println(i + ": " + a + "/" + b + "=");
                    int c0 = in.nextInt();
                    out.println(a + "/" + b + "=" + c0);
                    if (c0 == counter.d(a, b)) {
                        sum += 10;
                        System.out.println("正确!");
                    } else {
                        System.out.println("错误!");
                    }
     break;
    
                case 2:
                    System.out.println(i + ": " + a + "*" + b + "=");
                    int c = in.nextInt();
                    out.println(a + "*" + b + "=" + c);
                    if (c == counter.m(a, b)) {
                        sum+= 10;
                        System.out.println("正确!");
                    } else {
                        System.out.println("错误!");
                    }
                    break;
                case 3:
                    System.out.println(i + ": " + a + "+" + b + "=");
                    int c1 = in.nextInt();
                    out.println(a + "+" + b + "=" + c1);
                    if (c1 == counter.add(a, b)) {
                        sum += 10;
                        System.out.println("正确!");
                    } else {
                        System.out.println("错误!");
                    }
                    break;
                case 4:
                    while (a < b) {
                        b = (int) Math.round(Math.random() * 100);
                    }
                  //因为不能产生运算结果为负数的减法式子,所以a一定要大于b。若a<b,则重新生成b。
                    System.out.println(i + ": " + a + "-" + b + "=");
                    int c2 = in.nextInt();
                    out.println(a + "-" + b + "=" + c2);
                    if (c2 == counter.r(a, b)) {
                        sum += 10;
                        System.out.println("正确!");
                    } else {
                        System.out.println("错误!");
                    }
                    break;
                }
            }
            System.out.println("成绩" + sum);
            out.println("成绩:" + sum);
            out.close();
        }
    }
    Main
    package C;
    public class Suanfa<T> {
        private T a;
        private T b;
       public int add(int a,int b) {
            return a + b;
        }
    
        public int r(int a, int b) {
            return a - b;
        }
    
        public int m(int a, int b) {
            return a * b;
        }
    
        public int d(int a, int b) {
            if (b != 0 && a%b==0)
                return a / b;
            else
                return 0;
        }
    }
    Suanfa

    3)    结对程序运行功能界面截图;

    4)    结对过程描述,提供两人在讨论、细化和编程时的结对照片(非摆拍)

    在测试过互相的程序后,发现了各自的不足之处,以后会加以改进,然后我们二人又重新开始对以上的程序进行了修改,简化,得出了结果,果然合作的话会有更大的发展空间,还能发现更多的问题。

    总结:本章我们学习了Vetor、Stack、Hashtable三个类的用途及常用API;我在测试代码实验中,通过注释,编译逐渐理解了本周理论知识所讲的知识,感受到了它们的区别和联系,在本周实验中还增加了一个结对实验,这个合作实验让我们发现了彼此的不足和需要改进的地方,是 个很好的相互学习的过程。

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  • 原文地址:https://www.cnblogs.com/YRQY/p/9928610.html
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