Java
java练习总结
1.前言：
本次主要分析Java中图形类的设计的题目，Java实现单向以及双向链表类练习，以及Java中容器类的设计；
考查难度由易到难，层层递进，前面的题目即为后面的代码做了很大的设计铺垫。
2.题目分析：
1.点线形系列-计算两点之间的距离
输入连个点的坐标，计算两点之间的距离
输入格式:
4个double类型的实数，两个点的x，y坐标，依次是x1、y1、x2、y2，两个点的坐标之间以空格分隔，每个点的x,y坐标以英文“,”分隔。例如：0,0 1,1或0.1,-0.3 +3.5,15.6。
若输入格式非法，输出”Wrong Format”。
若输入格式合法但坐标点的数量超过两个，输出“wrong number of points”。
输出格式:
计算所得的两点之间的距离。例如：1.4142135623730951
源代码如下：
1 import java.util.Scanner; 2 public class Main { 3 public static void main(String[] args) { 4 double result = 0; 5 String x1; 6 String x2; 7 String y1; 8 String y2; 9 int e=0,f=0,g=0,h=0,k=0; 10 String firstCoordinate; 11 String secondCoordinate; 12 Scanner in = new Scanner(System.in); 13 String input = in.nextLine(); 14 for(int i=0;i<input.length();i++) 15 { 16 if(input.charAt(i)==' ') 17 f++; 18 } 19 if(f==0) 20 System.out.println("Wrong Format"); 21 String[] inpute = input.split(" "); 22 firstCoordinate = inpute[0]; 23 secondCoordinate = inpute[1]; 24 if(inpute.length<=2) 25 { 26 for(int i=0;i<firstCoordinate.length();i++) 27 { 28 if(firstCoordinate.charAt(i)==',') 29 g++; 30 } 31 for(int i=0;i<secondCoordinate.length();i++) 32 { 33 if(secondCoordinate.charAt(i)==',') 34 h++; 35 } 36 if(g==0||h==0) 37 System.out.println("Wrong Format"); 38 else 39 { 40 String[] first = firstCoordinate.split(","); 41 String[] second = secondCoordinate.split(","); 42 if(first.length==2&&second.length==2) 43 { 44 x1 = first[0]; 45 y1 = first[1]; 46 x2 = second[0]; 47 y2 = second[1]; 48 for(int i=0;i<x1.length();i++) 49 { 50 if(x1.charAt(i)=='+'||x1.charAt(i)=='-') 51 e++; 52 if(x1.charAt(i)=='.'&&i==x1.length()-1) 53 k++; 54 } 55 if(e>=2||(e==1&&x1.charAt(0)!='+'&&x1.charAt(0)!='-')||k==1) 56 System.out.println("Wrong Format"); 57 else 58 { 59 e=0; 60 k=0; 61 for(int i=0;i<y1.length();i++) 62 { 63 if(y1.charAt(i)=='+'||y1.charAt(i)=='-') 64 e++; 65 if(y1.charAt(i)=='.'&&i==y1.length()-1) 66 k++; 67 } 68 if(e>=2||(e==1&&y1.charAt(0)!='+'&&y1.charAt(0)!='-')||k==1) 69 System.out.println("Wrong Format"); 70 else 71 { 72 e=0; 73 k=0; 74 for(int i=0;i<x2.length();i++) 75 { 76 if(x2.charAt(i)=='+'||x2.charAt(i)=='-') 77 e++; 78 if(x2.charAt(i)=='.'&&i==x2.length()-1) 79 k++; 80 } 81 if(e>=2||(e==1&&x2.charAt(0)!='+'&&x2.charAt(0)!='-')||k==1) 82 System.out.println("Wrong Format"); 83 else 84 { 85 e=0; 86 k=0; 87 for(int i=0;i<y2.length();i++) 88 { 89 if(y2.charAt(i)=='+'||y2.charAt(i)=='-') 90 e++; 91 if(y2.charAt(i)=='.'&&i==y2.length()-1) 92 k++; 93 } 94 if(e>=2||(e==1&&y2.charAt(0)!='+'&&y2.charAt(0)!='-')||k==1) 95 System.out.println("Wrong Format"); 96 else 97 { 98 if((x1.charAt(0)=='0'&&x1.length()>=2&&x1.charAt(1)!='.')||(x2.charAt(0)=='0'&&x2.length()>=2&&x2.charAt(1)!='.')||(y1.charAt(0)=='0'&&y1.length()>=2&&y1.charAt(1)!='.')||(y2.charAt(0)=='0'&&y2.length()>=2&&y2.charAt(1)!='.')) 99 System.out.println("Wrong Format"); 100 else 101 { 102 double a = Double.parseDouble(x1); 103 double b = Double.parseDouble(y1); 104 double c = Double.parseDouble(x2); 105 double d = Double.parseDouble(y2); 106 result = Math.sqrt(Math.pow(a-c,2)+Math.pow(b-d,2)); 107 System.out.println(result); 108 } 109 } 110 } 111 } 112 } 113 } 114 else 115 System.out.println("Wrong Format"); 116 } 117 } 118 else 119 System.out.println("wrong number of points"); 120 } 121 }
代码分析：
本题重点在于对非法输入的判断；运用已知条件进行边界的测试，保证代码的严谨合理性。
采坑心得：
对于一些日常不会考虑的问题也应该进行判断，如”0.”,”1.”,”1++”,”–1″,”+1+”,”0.0″等情况，是可能会缺乏考虑的.运用合理的方法进行数值的筛选，以达到合法的输入。
2.点线形系列-三角形的计算
用户输入一组选项和数据，进行与三角形有关的计算。选项包括：
1：输入三个点坐标，判断是否是等腰三角形、等边三角形，判断结果输出true/false，两个结果之间以一个英文空格符分隔。
2：输入三个点坐标，输出周长、面积、重心坐标，三个参数之间以一个英文空格分隔，坐标之间以英文”,”分隔。
3：输入三个点坐标，输出是钝角、直角还是锐角三角形，依次输出三个判断结果（true/false），以一个英文空格分隔，
4：输入五个点坐标，输出前两个点所在的直线与三个点所构成的三角形相交的交点数量，如果交点有两个，则按面积大小依次输出三角形被直线分割成两部分的面积。若直线与三角形一条线重合，输出”The point is on the edge of the triangle”
5：输入四个点坐标，输出第一个是否在后三个点所构成的三角形的内部（输出in the triangle/outof triangle）。
必须使用射线法，原理：由第一个点往任一方向做一射线，射线与三角形的边的交点（不含点本身）数量如果为1，则在三角形内部。如果交点有两个或0个，则在三角形之外。若点在三角形的某条边上，输出”on the triangle”
输入格式:
基本格式：选项+”:”+坐标x+”,”+坐标y+” “+坐标x+”,”+坐标y。点的x、y坐标之间以英文”,”分隔，点与点之间以一个英文空格分隔。
输出格式:
基本输出格式见每种选项的描述。
异常情况输出：
如果不符合基本格式，输出”Wrong Format”。
如果符合基本格式，但输入点的数量不符合要求，输出”wrong number of points”。
如果输入的三个点无法构成三角形，输出”data error”。
注意：输出的数据若小数点后超过6位，只保留小数点后6位，多余部分采用四舍五入规则进到最低位。小数点后若不足6位，按原始位数显示，不必补齐。例如：1/3的结果按格式输出为 0.333333，1.0按格式输出为1.0
选项4中所输入线的两个点坐标重合，输出”points coincide”，
1.源代码如下：
import java.util.Scanner; public class Main { public static void main(String[] args) { // TODO Auto-generated method stub Scanner in = new Scanner (System.in); String str = in.nextLine(); if(str.charAt(0)=='1') { int a=0; String x1; String x2; String y1; String y2; String z1; String z2; int e=0,f=0,g=0,h=0,k=0; double result=0; String input0 = str.substring(2); for(int i=0;i<input0.length();i++) { if(input0.charAt(i)==' ') a++; } if(a!=2) System.out.println("Wrong Format"); else { String firstCoordinate; String secondCoordinate; String thirdCoordinate; String[] input1 = input0.split(" "); firstCoordinate = input1[0]; secondCoordinate = input1[1]; thirdCoordinate = input1[2]; if(input1.length<=3) { for(int i=0;i<firstCoordinate.length();i++) { if(firstCoordinate.charAt(i)==',') g++; } for(int i=0;i<secondCoordinate.length();i++) { if(secondCoordinate.charAt(i)==',') h++; } for(int i=0;i<thirdCoordinate.length();i++) { if(thirdCoordinate.charAt(i)==',') f++; } if(g==0||h==0||f==0) System.out.println("Wrong Format"); else { String[] first = firstCoordinate.split(","); String[] second = secondCoordinate.split(","); String[] third = thirdCoordinate.split(","); if(first.length==2&&second.length==2&&third.length==2) { x1 = first[0]; y1 = first[1]; x2 = second[0]; y2 = second[1]; z1 = third[0]; z2 = third[1]; for(int i=0;i<x1.length();i++) { if(x1.charAt(i)=='+'||x1.charAt(i)=='-') e++; if(x1.charAt(i)=='.'&&i==x1.length()-1) k++; } if(e>=2||(e==1&&x1.charAt(0)!='+'&&x1.charAt(0)!='-')||k==1) System.out.println("Wrong Format"); else { e=0; k=0; for(int i=0;i<y1.length();i++) { if(y1.charAt(i)=='+'||y1.charAt(i)=='-') e++; if(y1.charAt(i)=='.'&&i==y1.length()-1) k++; } if(e>=2||(e==1&&y1.charAt(0)!='+'&&y1.charAt(0)!='-')||k==1) System.out.println("Wrong Format"); else { e=0; k=0; for(int i=0;i<x2.length();i++) { if(x2.charAt(i)=='+'||x2.charAt(i)=='-') e++; if(x2.charAt(i)=='.'&&i==x2.length()-1) k++; } if(e>=2||(e==1&&x2.charAt(0)!='+'&&x2.charAt(0)!='-')||k==1) System.out.println("Wrong Format"); else { e=0; k=0; for(int i=0;i<y2.length();i++) { if(y2.charAt(i)=='+'||y2.charAt(i)=='-') e++; if(y2.charAt(i)=='.'&&i==y2.length()-1) k++; } if(e>=2||(e==1&&y2.charAt(0)!='+'&&y2.charAt(0)!='-')||k==1) System.out.println("Wrong Format"); else { e=0; k=0; for(int i=0;i<z1.length();i++) { if(z1.charAt(i)=='+'||z1.charAt(i)=='-') e++; if(z1.charAt(i)=='.'&&i==z1.length()-1) k++; } if(e>=2||(e==1&&z1.charAt(0)!='+'&&z1.charAt(0)!='-')||k==1) System.out.println("Wrong Format"); else { e=0; k=0; for(int i=0;i<z2.length();i++) { if(z2.charAt(i)=='+'||z2.charAt(i)=='-') e++; if(z2.charAt(i)=='.'&&i==z2.length()-1) k++; } if(e>=2||(e==1&&z2.charAt(0)!='+'&&z2.charAt(0)!='-')||k==1) System.out.println("Wrong Format"); else { if((x1.charAt(0)=='0'&&x1.length()>=2&&x1.charAt(1)!='.')||(x2.charAt(0)=='0'&&x2.length()>=2&&x2.charAt(1)!='.')||(y1.charAt(0)=='0'&&y1.length()>=2&&y1.charAt(1)!='.')||(y2.charAt(0)=='0'&&y2.length()>=2&&y2.charAt(1)!='.')||(z1.charAt(0)=='0'&&z1.length()>=2&&z1.charAt(1)!='.')||(z2.charAt(0)=='0'&&z2.length()>=2&&z2.charAt(1)!='.')) System.out.println("Wrong Format"); else { double a1 = Double.parseDouble(x1); double b1 = Double.parseDouble(y1); double a2 = Double.parseDouble(x2); double b2 = Double.parseDouble(y2); double a3 = Double.parseDouble(z1); double b3 = Double.parseDouble(z2); double a01 = Math.sqrt(Math.pow(b2-b1, 2)+Math.pow(a2-a1, 2)); double b01 = Math.sqrt(Math.pow(b3-b2, 2)+Math.pow(a3-a2, 2)); double c01 = Math.sqrt(Math.pow(b3-b1, 2)+Math.pow(a3-a1, 2)); result =Math.abs((b2-b3)*a1+(a3-a2)*b1+a2*b3-b2*a3)/Math.sqrt((b2-b3)*(b2-b3) +(a2-a3)*(a2-a3)); if(result==0) { System.out.print("data error"); } else { if(a01==b01||a01==c01||b01==c01) { if(a01==b01&&a01==c01&&b01==c01) { System.out.print("true true"); } else System.out.print("true false"); } else { System.out.print("false false"); } } } } } } } } } } else System.out.println("Wrong Format"); } } else System.out.println("wrong number of points"); } } if(str.charAt(0)=='2') { String x1; String x2; String y1; String y2; String z1; String z2; double result0 = 0; double result1 = 0; double resultx = 0; double resulty = 0; String input0 = str.substring(2); String firstCoordinate; String secondCoordinate; String thirdCoordinate; String[] input1 = input0.split(" "); firstCoordinate = input1[0]; secondCoordinate = input1[1]; thirdCoordinate = input1[2]; String[] first = firstCoordinate.split(","); String[] second = secondCoordinate.split(","); String[] third = thirdCoordinate.split(","); x1 = first[0]; y1 = first[1]; x2 = second[0]; y2 = second[1]; z1 = third[0]; z2 = third[1]; double a1 = Double.parseDouble(x1); double b1 = Double.parseDouble(y1); double a2 = Double.parseDouble(x2); double b2 = Double.parseDouble(y2); double a3 = Double.parseDouble(z1); double b3 = Double.parseDouble(z2); double a01 = Math.sqrt(Math.pow(b2-b1, 2)+Math.pow(a2-a1, 2)); double b01 = Math.sqrt(Math.pow(b3-b2, 2)+Math.pow(a3-a2, 2)); double c01 = Math.sqrt(Math.pow(b3-b1, 2)+Math.pow(a3-a1, 2)); result0 = a01+b01+c01; result1 = Math.sqrt(0.5*result0*(0.5*result0-a01)*(0.5*result0-b01)*(0.5*result0-c01)); resultx = (a1+a2+a3)/3; resulty = (b1+b2+b3)/3; System.out.println((double)(Math.round(result0*1000000)/1000000.0)+" "+(double)(Math.round(result1*1000000)/1000000.0)+" "+ (double)(Math.round(resultx*1000000)/1000000.0)+","+(double)(Math.round(resulty*1000000)/1000000.0)); } if(str.charAt(0)=='3') { String x1; String x2; String y1; String y2; String z1; String z2; double result = 0; String input0 = str.substring(2); String firstCoordinate; String secondCoordinate; String thirdCoordinate; String[] input1 = input0.split(" "); firstCoordinate = input1[0]; secondCoordinate = input1[1]; thirdCoordinate = input1[2]; String[] first = firstCoordinate.split(","); String[] second = secondCoordinate.split(","); String[] third = thirdCoordinate.split(","); x1 = first[0]; y1 = first[1]; x2 = second[0]; y2 = second[1]; z1 = third[0]; z2 = third[1]; double a1 = Double.parseDouble(x1); double b1 = Double.parseDouble(y1); double a2 = Double.parseDouble(x2); double b2 = Double.parseDouble(y2); double a3 = Double.parseDouble(z1); double b3 = Double.parseDouble(z2); double a01 = Math.sqrt(Math.pow(b2-b1, 2)+Math.pow(a2-a1, 2)); double b01 = Math.sqrt(Math.pow(b3-b2, 2)+Math.pow(a3-a2, 2)); double c01 = Math.sqrt(Math.pow(b3-b1, 2)+Math.pow(a3-a1, 2)); if(a01+b01<c01||b01+c01<a01||a01+c01<b01) { System.out.print("data error"); } else { if(Math.pow(a01, 2)+Math.pow(b01, 2)<Math.pow(c01, 2)||Math.pow(a01, 2)+Math.pow(c01, 2)<Math.pow(b01, 2)||Math.pow(b01, 2)+Math.pow(c01, 2)<Math.pow(a01, 2)) { System.out.print("true false false"); } else if(Math.abs(Math.pow(a01, 2)+Math.pow(b01, 2)-Math.pow(c01, 2))<0.000001||Math.abs(Math.pow(a01, 2)+Math.pow(c01, 2)-Math.pow(b01, 2))<0.000001||Math.abs(Math.pow(b01, 2)+Math.pow(c01, 2)-Math.pow(a01, 2))<0.000001) { System.out.print("false true false"); } else System.out.print("false false true"); } } if(str.charAt(0)=='4') { String x1; String x2; String y1; String y2; String z1; String z2; String p1; String p2; String q1; String q2; double result0 = 0; double result1 = 0; String input0 = str.substring(2); String firstCoordinate; String secondCoordinate; String thirdCoordinate; String forthCoordinate; String fifthCoordinate; String[] input1 = input0.split(" "); firstCoordinate = input1[0]; secondCoordinate = input1[1]; thirdCoordinate = input1[2]; forthCoordinate = input1[3]; fifthCoordinate = input1[4]; String[] first = firstCoordinate.split(","); String[] second = secondCoordinate.split(","); String[] third = thirdCoordinate.split(","); String[] forth = forthCoordinate.split(","); String[] fifth = fifthCoordinate.split(","); x1 = first[0]; y1 = first[1]; x2 = second[0]; y2 = second[1]; z1 = third[0]; z2 = third[1]; p1 = forth[0]; p2 = forth[1]; q1 = fifth[0]; q2 = fifth[1]; double a1 = Double.parseDouble(x1); double b1 = Double.parseDouble(y1); double a2 = Double.parseDouble(x2); double b2 = Double.parseDouble(y2); double a3 = Double.parseDouble(z1); double b3 = Double.parseDouble(z2); double a4 = Double.parseDouble(p1); double b4 = Double.parseDouble(p2); double a5 = Double.parseDouble(q1); double b5 = Double.parseDouble(q2); result0 = (b1-b2)/(a1-a2); result1 = (b3-b4)/(a3-a4); if(result0 == result1) System.out.println("true"); else System.out.println("false"); } if(str.charAt(0)=='5') { String x1; String x2; String y1; String y2; String z1; String z2; String p1; String p2; double result0 = 0; double result1 = 0; double result2 = 0; String input0 = str.substring(2); String firstCoordinate; String secondCoordinate; String thirdCoordinate; String forthCoordinate; String[] input1 = input0.split(" "); firstCoordinate = input1[0]; secondCoordinate = input1[1]; thirdCoordinate = input1[2]; forthCoordinate = input1[3]; String[] first = firstCoordinate.split(","); String[] second = secondCoordinate.split(","); String[] third = thirdCoordinate.split(","); String[] forth = forthCoordinate.split(","); x1 = first[0]; y1 = first[1]; x2 = second[0]; y2 = second[1]; z1 = third[0]; z2 = third[1]; p1 = forth[0]; p2 = forth[1]; double a1 = Double.parseDouble(x1); double b1 = Double.parseDouble(y1); double a2 = Double.parseDouble(x2); double b2 = Double.parseDouble(y2); double a3 = Double.parseDouble(z1); double b3 = Double.parseDouble(z2); double a4 = Double.parseDouble(p1); double b4 = Double.parseDouble(p2); result0 = Math.abs((b2-b3)*a1+(a3-a2)*b1+a2*b3-b2*a3)/Math.sqrt((b2-b3)*(b2-b3) +(a2-a3)*(a2-a3)); result1 = Math.abs((b3-b4)*a1+(a4-a3)*b1+a3*b4-b3*a4)/Math.sqrt((b3-b4)*(b3-b4) +(a3-a4)*(a3-a4)); result2 = Math.abs((b2-b4)*a1+(a4-a2)*b1+a2*b4-b2*a4)/Math.sqrt((b2-b4)*(b2-b4) +(a2-a4)*(a2-a4)); double a01 = Math.sqrt(Math.pow(b2-b3, 2)+Math.pow(a2-a3, 2)); double b01 = Math.sqrt(Math.pow(b3-b4, 2)+Math.pow(a3-a4, 2)); double c01 = Math.sqrt(Math.pow(b2-b4, 2)+Math.pow(a2-a4, 2)); if(a01+b01<c01||b01+c01<a01||a01+c01<b01) { System.out.print("data error"); } else { if(result0==0||result1==0||result2==0) System.out.print("on the triangle"); else { if(result0*a01+result1*b01+result2*c01==Math.sqrt(0.5*result0*(0.5*result0-a01)*(0.5*result0-b01)*(0.5*result0-c01))) System.out.print("in the triangle"); else System.out.print("outof the triangle"); } } } } }
题目分析：
此题应当分方法进行合理的规划，以避免代码的大量重复，类的设计以及方法的设计都十分考验Java水准，要仔细思考再下手码代码。
采坑心得：
本题我的代码不建议借鉴，可以当作一个反例，写编程题一点不要性急，重在分析题目，整理思路，可以设计一个通用的父类以减少代码的重复性，提高代码的可扩展性和复用性。
3.Java实现单链表功能：
使用Java实现链表功能，具体功能如下（参考）：
public interface LinearListInterface <E>{
public boolean isEmpty();
public int getSize();
public E get(int index);
public void remove(int index);
public void add(int index, E theElement);
public void add(E element);
public void printList();
}
结构如下：
//LinkedList class
public class LList<E>{
private Node<E> head,curr,tail;//头结点（非第一个节点），当前节点，尾节点
private int size = 0;
}
//Node
public class Node<E>{
private E data;
private Node<E> next;
}
源代码如下：
1 interface LinearListInterface<E> { 2 3 public boolean isEmpty(); 4 5 public int size(); 6 7 public E get(int index); 8 9 public void remove(int index); 10 11 public void add(int index, E theElement); 12 13 public void add(E element); 14 15 public void printList(); 16 17 } 18 19 class LList<E>implements LinearListInterface<E>{ 20 21 private Node<E> head,curr,tail; 22 private int size; 23 public boolean isEmpty() { 24 if(this.tail==null) { 25 return false; 26 } 27 return true; 28 } 29 public int size() { 30 return this.size; 31 } 32 public E get(int index) { 33 int count = 0; 34 if(index>=0&&index<=size) 35 { 36 this.curr = head; 37 while(count<index) 38 { 39 this.curr = this.curr.next; 40 count++; 41 } 42 return this.curr.o; 43 } 44 return null; 45 } 46 public void remove(int index) { 47 int count = 0; 48 if(index>=0&&index<=size) { 49 if(index==0) { 50 this.head = this.head.next; 51 this.size--; 52 }else { 53 this.curr = this.head; 54 while(count<index-1) { 55 this.curr = this.curr.next; 56 count++; 57 } 58 this.curr.next = this.curr.next.next; 59 } 60 this.size--; 61 } 62 } 63 public void add(int index, E theElement) { 64 int count = 0; 65 if(index>=0&&index<=this.size) { 66 if(index==0) { 67 this.head = new Node<E>(theElement,this.head); 68 }else { 69 this.curr = head; 70 while(count<index-1) { 71 this.curr = this.curr.next; 72 count++; 73 } 74 this.curr.next = new Node<E>(theElement,this.curr.next); 75 } 76 this.size++; 77 } 78 } 79 public void add(E element) { 80 Node<E> node =new Node<E>(element,null); 81 this.curr = this.tail;// 82 this.tail = node; 83 if(curr==null) { 84 head = node; 85 }else{ 86 curr.next = node; 87 } 88 this.size++; 89 } 90 public void printList() { 91 for(int i = 0;i<this.size;i++) { 92 System.out.print(get(i).toString()+" "); 93 } 94 } 95 } 96 97 98 class Node<E>{ 99 100 private E o; 101 102 private Node<E> next; 103 104 }
分析：
链表是java数据结构中一种很基础很常见却也很重要的数据结构，它的结构如下：
链表的基本操作
包括链表的增删查改，以及判别某结点是否存在链表中，链表的结构很简单，就是一个个节点连接在一起，形成一个完整的链条，每个节点包含2部分，数据域，和一个指向下一个节点引用的指针next,，再说说删除操作，同样需要找到数据所在的位置，然后进行删除，不同的是，删除的时候，链表只需要改变一下前后节点的引用关系即可，就完成了节点的删除，而没有像数组那样触发一次全部数据的移动。
4. 点与线（类设计）
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设计一个类表示平面直角坐标系上的点Point，私有属性分别为横坐标x与纵坐标y，数据类型均为实型数，除构造方法以及属性的getter与setter方法外，定义一个用于显示信息的方法display(),用来输出该坐标点的坐标信息，格式如下：
(x,y)，数值保留两位小数。为简化题目，其中，坐标点的取值范围设定为(0,200]。若输入有误，系统则直接输出Wrong Format -
设计一个类表示平面直角坐标系上的线Line，私有属性除了标识线段两端的点point1、point2外，还有一个字符串类型的color，用于表示该线段的颜色，同样，除构造方法以及属性的getter与setter方法外，定义一个用于计算该线段长度的方法getDistance(),还有一个用于显示信息的方法display(),用来输出线段的相关信息，输出格式如下：
``` The line's color is:颜色值 The line's begin point's Coordinate is: (x1,y1) The line's end point's Coordinate is: (x2,y2) The line's length is:长度值 ```其中，所有数值均保留两位小数，建议可用
String.format("%.2f", data)方法。 - 类图如下：
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输入格式:
分别输入线段的起点横坐标、纵坐标、终点的横坐标、纵坐标以及颜色，中间可用一个或多个空格、tab或者回车分隔。
输出格式:
The line's color is:颜色值 The line's begin point's Coordinate is: (x1,y1) The line's end point's Coordinate is: (x2,y2) The line's length is:长度值 -
源代码如下：
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1 import java.util.Scanner; 2 3 public class Main { 4 5 public static void main(String[] args) { 6 // TODO Auto-generated method stub 7 Scanner in = new Scanner(System.in); 8 Point p1 = new Point(); 9 String color = null; 10 Point p2 = new Point(); 11 p1.setX(in.nextDouble()); 12 p1.setY(in.nextDouble()); 13 p2.setX(in.nextDouble()); 14 p2.setY(in.nextDouble()); 15 color = in.next(); 16 Line line =new Line( p1, p2, color); 17 line.display(); 18 } 19 20 } 21 class Point{ 22 private double x; 23 private double y; 24 public Point() { 25 super(); 26 // TODO Auto-generated constructor stub 27 } 28 public Point(double x, double y) { 29 super(); 30 this.x = x; 31 this.y = y; 32 } 33 public double getX() { 34 return x; 35 } 36 public void setX(double x) { 37 this.x = x; 38 } 39 public double getY() { 40 return y; 41 } 42 public void setY(double y) { 43 this.y = y; 44 } 45 public void display() { 46 if(x>0&&x<=200&&y>0&&y<=200) { 47 System.out.printf("(%.2f,%.2f)\n",x,y); 48 } 49 else 50 System.out.print("Wrong Format"); 51 } 52 } 53 class Line{ 54 private Point point1; 55 private Point point2; 56 private String color; 57 public Line() { 58 super(); 59 // TODO Auto-generated constructor stub 60 } 61 public Line(Point p1, Point p2, String color) { 62 super(); 63 this.point1 = p1; 64 this.point2 = p2; 65 this.color = color; 66 } 67 public Point getPoint1() { 68 return point1; 69 } 70 public void setPoint1(Point point1) { 71 this.point1 = point1; 72 } 73 public Point getPoint2() { 74 return point2; 75 } 76 public void setPoint2(Point point2) { 77 this.point2 = point2; 78 } 79 public String getColor() { 80 return color; 81 } 82 public void setColor(String color) { 83 this.color = color; 84 } 85 public double getDistence() { 86 double result; 87 result = Math.abs(Math.sqrt((Math.pow(point1.getY()-point2.getY(), 2))+(Math.pow(point1.getX()-point2.getX(), 2)))); 88 return result; 89 } 90 public void display() { 91 if(point1.getX()<=0||point1.getX()>200||point1.getY()<=0||point1.getY()>200||point2.getX()<=0||point2.getX()>200||point2.getY()<=0||point2.getY()>200) 92 { 93 System.out.printf("Wrong Format"); 94 } 95 else { 96 System.out.printf("The line's color is:%s\n",color); 97 System.out.printf("The line's begin point's Coordinate is:\n"); 98 point1.display(); 99 System.out.printf("The line's end point's Coordinate is:\n"); 100 point2.display(); 101 System.out.printf("The line's length is:%.2f",getDistence()); 102 } 103 104 } 105 }
分析及采坑心得：
- 本题主要考察对类图的运用，要知道怎么看类图，做到自己写出的代码结构的类图与题目给出的类图契合是本题的重中之重，学会按类图的要求来设计类是编程的基本功。本题较易，后面两题是这道题的层层递进，由易到难。
5.点线面问题重构（继承与多态）
在“点与线（类设计）”题目基础上，对题目的类设计进行重构，以实现继承与多态的技术性需求。
- 对题目中的点Point类和线Line类进行进一步抽象，定义一个两个类的共同父类Element（抽象类），将display()方法在该方法中进行声明（抽象方法），将Point类和Line类作为该类的子类。
- 再定义一个Element类的子类面Plane，该类只有一个私有属性颜色color，除了构造方法和属性的getter、setter方法外，display()方法用于输出面的颜色，输出格式如下：
The Plane's color is:颜色 - 在主方法内，定义两个Point（线段的起点和终点）对象、一个Line对象和一个Plane对象，依次从键盘输入两个Point对象的起点、终点坐标和颜色值（Line对象和Plane对象颜色相同），然后定义一个Element类的引用，分别使用该引用调用以上四个对象的display()方法，从而实现多态特性。示例代码如下：
element = p1;//起点Point element.display(); element = p2;//终点Point element.display(); element = line;//线段 element.display(); element = plane;//面 element.display(); - 类结构如下图所示：
- 源代码如下：
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1 import java.util.Scanner; 2 3 public class Main { 4 5 public static void main(String[] args) { 6 // TODO Auto-generated method stub 7 Scanner in = new Scanner(System.in); 8 Point p1 = new Point(); 9 String color = null; 10 Point p2 = new Point(); 11 p1.setX(in.nextDouble()); 12 p1.setY(in.nextDouble()); 13 p2.setX(in.nextDouble()); 14 p2.setY(in.nextDouble()); 15 color = in.next(); 16 Plane plane = new Plane(color); 17 Line line =new Line( p1, p2, color); 18 Element element; 19 if(p1.getX()<=0||p1.getX()>200||p1.getY()<=0||p1.getY()>200||p2.getX()<=0||p2.getX()>200||p2.getY()<=0||p2.getY()>200) 20 { 21 System.out.print("Wrong Format"); 22 }else { 23 element = p1;//起点Point 24 element.display(); 25 26 element = p2;//终点Point 27 element.display(); 28 29 element = line;//线段 30 element.display(); 31 32 element = plane;//面 33 element.display(); 34 } 35 36 37 } 38 39 } 40 class Point extends Element{ 41 private double x; 42 private double y; 43 public Point() { 44 super(); 45 // TODO Auto-generated constructor stub 46 } 47 public Point(double x, double y) { 48 super(); 49 this.x = x; 50 this.y = y; 51 } 52 public double getX() { 53 return x; 54 } 55 public void setX(double x) { 56 this.x = x; 57 } 58 public double getY() { 59 return y; 60 } 61 public void setY(double y) { 62 this.y = y; 63 } 64 @Override 65 public void display() { 66 if(x<=0||x>200||y<=0||y>200) { 67 System.out.print("Wrong Format"); 68 System.exit(0); 69 } 70 else { 71 System.out.printf("(%.2f,%.2f)\n",x,y); 72 } 73 } 74 } 75 class Line extends Element{ 76 private Point point1; 77 private Point point2; 78 private String color; 79 public Line() { 80 super(); 81 // TODO Auto-generated constructor stub 82 } 83 public Line(Point p1, Point p2, String color) { 84 super(); 85 this.point1 = p1; 86 this.point2 = p2; 87 this.color = color; 88 } 89 public Point getPoint1() { 90 return point1; 91 } 92 public void setPoint1(Point point1) { 93 this.point1 = point1; 94 } 95 public Point getPoint2() { 96 return point2; 97 } 98 public void setPoint2(Point point2) { 99 this.point2 = point2; 100 } 101 public String getColor() { 102 return color; 103 } 104 public void setColor(String color) { 105 this.color = color; 106 } 107 public double getDistence() { 108 double result; 109 result = Math.abs(Math.sqrt((Math.pow(point1.getY()-point2.getY(), 2))+(Math.pow(point1.getX()-point2.getX(), 2)))); 110 return result; 111 } 112 @Override 113 public void display() { 114 if(point1.getX()<=0||point1.getX()>200||point1.getY()<=0||point1.getY()>200||point2.getX()<=0||point2.getX()>200||point2.getY()<=0||point2.getY()>200) 115 { 116 System.out.printf("Wrong Format"); 117 } 118 else { 119 System.out.printf("The line's color is:%s\n",color); 120 System.out.printf("The line's begin point's Coordinate is:\n"); 121 point1.display(); 122 System.out.printf("The line's end point's Coordinate is:\n"); 123 point2.display(); 124 System.out.printf("The line's length is:%.2f\n",getDistence()); 125 } 126 127 } 128 } 129 abstract class Element{ 130 abstract protected void display(); 131 } 132 133 class Plane extends Element{ 134 String color; 135 136 public Plane() { 137 super(); 138 // TODO Auto-generated constructor stub 139 } 140 141 public Plane(String color) { 142 super(); 143 this.color = color; 144 } 145 146 public String getColor() { 147 return color; 148 } 149 150 public void setColor(String color) { 151 this.color = color; 152 } 153 154 @Override 155 public void display() { 156 System.out.printf("The Plane's color is:%s",color); 157 } 158 159 }
本题分析：
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这题在第一题的基础上增加了类以及对应的方法；较第一题难度上升但同样考查对类的合理规划与设计。
6.ATM机类结构设计
编写一个银行 ATM 机的模拟程序，能够完成用户的存款、取款以及查询余额功能
（1）相关概念说明
⚫中国银联（China UnionPay）：成立于 2002 年 3 月，是经国务院同意，中 国人民银行批准设立的中国银行卡联合组织，总部设于上海。主要负责建设和 运营全国统一的银行卡跨行信息交换网络、提供银行卡跨行信息交换相关的专 业化服务、管理和经营“银联”品牌、制定银行卡跨行交易业务规范和技术标 准。其包含多家银行机构。
⚫银行（Bank）：是依法成立的经营货币信贷业务的金融机构，是商品货币经 济发展到一定阶段的产物。
⚫银行用户（User）：能够在银行办理相应业务的用户。一个银行机构可以拥 有多个银行用户及多个银行账户，一个用户也可以在多个银行机构开立账户。 ⚫银行账户（Account）：客户在银行开立的存款账户、贷款账户、往来账户 的总称。一个银行用户可以拥有多个银行账户。
⚫银行卡（Card）：经批准由商业银行(含邮政金融机构) 向社会发行的具有 消费信用、转账结算、存取现金等全部或部分功能的信用支付工具。一个银行 账户可以发行多张银行卡。
⚫ ATM（Automated Teller Machine），自动柜员机，因大部分用于取款，又 称自动取款机。它是一种高度精密的机电一体化装置，利用磁性代码卡或智能 卡实现金融交易的自助服务，代替银行柜面人员的工作。可提取现金、查询存 款余额、进行账户之间资金划拨、余额查询等工作。一般 ATM 机隶属于某一银 行机构。
（2）设计要求 尝试使用面向对象技术对银行用户在 ATM 机上进行相关操作的模拟系统设 计，上述的相关概念均要设计为实体类，业务（控制）类请自行根据实际需要进 行扩充和完善。 注意：为降低难度，本次作业限定银行卡均为借记卡（不能透支），且不允 许跨行办理相关业务（例如在中国建设银行的 ATM 机上对其他银行的账户进行操 作）。 2.2 程序功能需求 （1）实现功能
基础数据的初始化；
用户存款、取款及查询余额功能。
（3）输入输出规则 1）输入规则 每一行输入一次业务操作，可以输入多行，最终以字符#终止。
具体每种业 务操作输入格式如下：
➢ 存款、取款功能输入数据格式 卡号 密码 ATM 机编号 金额（由一个或多个空格分隔） 其中，当金额大于 0 时，代表取款，否则代表存款。
➢ 查询余额功能输入数据格式 卡号 2）输出规则
①输入错误处理
如果输入卡号不存在，则输出“Sorry,this card does not exist.”。
如果输入 ATM 机编号不存在，则输出“Sorry,the ATM’s id is wrong.”。
如果输入银行卡密码错误，则输出“Sorry,your password is wrong.”。
如果输入取款金额大于账户余额，则输出“Sorry,your account balance is insufficient.”。
如果检测为跨行存取款，则输出“Sorry,cross-bank withdrawal is not supported.”。
②取款业务输出 输出共两行，格式分别为：
[用户姓名]在[银行名称]的[ATM 编号]上取款¥[金额] 当前余额为¥[金额]
其中，[]说明括起来的部分为输出属性或变量，金额均保留两位小数。
③存款业务输出 输出共两行，格式分别为：
[用户姓名]在[银行名称]的[ATM 编号]上存款¥[金额] 当前余额为¥[金额]
其中，[]说明括起来的部分为输出属性或变量，金额均保留两位小数。
④查询余额业务输出 ¥[金额] 金额保留两位小数
源代码如下：
1 import java.util.Scanner; 2 3 public class Main { 4 5 public static void main(String[] args) { 6 // TODO Auto-generated method stub 7 Scanner in = new Scanner (System.in); 8 CCBDate ccbdate = new CCBDate(); 9 ICBCDate icbcdate = new ICBCDate(); 10 int i = 0; 11 String Password = null; 12 while(true) 13 { 14 atmCCB atmccb = new atmCCB(); 15 atmICBC atmicbc = new atmICBC(); 16 String CardNumber; 17 if(i!=0) 18 { 19 CardNumber=Password; 20 } 21 else 22 { 23 CardNumber = in.next(); 24 } 25 Password = null; 26 String AtmNumber; 27 float Money; 28 String Char; 29 i=0; 30 if(CardNumber.equals("#")) 31 System.exit(0); 32 else 33 Password = in.next(); 34 if(Password.equals("#")||Password.equals(icbcdate.getUser0_CardNumber01())||Password.equals(icbcdate.getUser0_CardNumber02())||Password.equals(icbcdate.getUser0_CardNumber1())||Password.equals(icbcdate.getUser0_CardNumber2())||Password.equals(icbcdate.getUser1_CardNumber1())||Password.equals(icbcdate.getUser1_CardNumber2())||Password.equals(ccbdate.getUser0_CardNumber01())||Password.equals(ccbdate.getUser0_CardNumber02())||Password.equals(ccbdate.getUser0_CardNumber1())||Password.equals(ccbdate.getUser1_CardNumber1())) 35 { 36 i++; 37 if(ccbdate.checkValidate(CardNumber, ccbdate)) 38 { 39 if(CardNumber.equals(ccbdate.getUser0_CardNumber01())||CardNumber.equals(ccbdate.getUser0_CardNumber02())) 40 { 41 System.out.printf("¥%.2f\n",ccbdate.getUser0_Card1Money()); 42 } 43 if(CardNumber.equals(ccbdate.getUser0_CardNumber1())) 44 { 45 System.out.printf("¥%.2f\n",ccbdate.getUser0_Card2Money()); 46 } 47 if(CardNumber.equals(ccbdate.getUser1_CardNumber1())) 48 { 49 System.out.printf("¥%.2f\n",ccbdate.getUser1_CardMoney()); 50 } 51 52 } 53 else 54 if(icbcdate.checkValidate(CardNumber, icbcdate)) 55 { 56 if(CardNumber.equals(icbcdate.getUser0_CardNumber1())) 57 { 58 System.out.printf("¥%.2f\n",icbcdate.getUser0_Card1Money()); 59 } 60 if(CardNumber.equals(icbcdate.getUser0_CardNumber2())) 61 { 62 System.out.printf("¥%.2f\n",icbcdate.getUser0_Card2Money()); 63 } 64 if(CardNumber.equals(icbcdate.getUser0_CardNumber01())||CardNumber.equals(icbcdate.getUser0_CardNumber02())) 65 { 66 System.out.printf("¥%.2f\n",icbcdate.getUser0_Card3Money()); 67 } 68 if(CardNumber.equals(icbcdate.getUser1_CardNumber1())) 69 { 70 System.out.printf("¥%.2f\n",icbcdate.getUser1_Card1Money()); 71 } 72 if(CardNumber.equals(icbcdate.getUser1_CardNumber2())) 73 { 74 System.out.printf("¥%.2f\n",icbcdate.getUser1_Card2Money()); 75 } 76 77 } 78 else { 79 System.out.println("Sorry,this card does not exist."); 80 System.exit(0); 81 } 82 83 } 84 85 else 86 { 87 AtmNumber = in.next(); 88 Money = in.nextFloat(); 89 if(ccbdate.checkValidate(CardNumber, ccbdate)) 90 { 91 if(Password.equals("88888888")) 92 { 93 atmccb.Chackvalidate(AtmNumber); 94 95 if(CardNumber.equals(ccbdate.getUser0_CardNumber01())||CardNumber.equals(ccbdate.getUser0_CardNumber02())) 96 { 97 if(Money>0) 98 { 99 if(Money>ccbdate.getUser0_Card1Money()) 100 System.out.print("Sorry,your account balance is insufficient."); 101 else 102 { 103 ccbdate.setUser0_Card1Money(ccbdate.getUser0_Card1Money()-Money); 104 System.out.print(ccbdate.getUser0_name()+"在中国建设银行的"+AtmNumber+"号ATM机上取款¥"); 105 System.out.printf("%.2f\n",Money); 106 System.out.printf("当前余额为¥%.2f\n",ccbdate.getUser0_Card1Money()); 107 } 108 } 109 else 110 if(Money<=0) 111 { 112 ccbdate.setUser0_Card1Money(ccbdate.getUser0_Card1Money()-Money); 113 System.out.print(ccbdate.getUser0_name()+"在中国建设银行的"+AtmNumber+"号ATM机上存款¥"); 114 System.out.printf("%.2f\n",-Money); 115 System.out.printf("当前余额为¥%.2f\n",ccbdate.getUser0_Card1Money()); 116 117 } 118 } 119 if(CardNumber.equals(ccbdate.getUser0_CardNumber1())) 120 { 121 if(Money>0) 122 { 123 if(Money>ccbdate.getUser0_Card2Money()) 124 System.out.print("Sorry,your account balance is insufficient."); 125 else 126 { 127 ccbdate.setUser0_Card2Money(ccbdate.getUser0_Card2Money()-Money); 128 System.out.print(ccbdate.getUser0_name()+"在中国建设银行的"+AtmNumber+"号ATM机上取款¥"); 129 System.out.printf("%.2f\n",Money); 130 System.out.printf("当前余额为¥%.2f\n",ccbdate.getUser0_Card2Money()); 131 } 132 } 133 else 134 if(Money<=0) 135 { 136 ccbdate.setUser0_Card2Money(ccbdate.getUser0_Card2Money()-Money); 137 System.out.print(ccbdate.getUser0_name()+"在中国建设银行的"+AtmNumber+"号ATM机上存款¥"); 138 System.out.printf("%.2f\n",-Money); 139 System.out.printf("当前余额为¥%.2f\n",ccbdate.getUser0_Card2Money()); 140 141 } 142 143 144 } 145 if(CardNumber.equals(ccbdate.getUser1_CardNumber1())) 146 { 147 if(Money>0) 148 { 149 if(Money>ccbdate.getUser1_CardMoney()) 150 System.out.print("Sorry,your account balance is insufficient."); 151 else 152 { 153 ccbdate.setUser1_CardMoney(ccbdate.getUser1_CardMoney()-Money); 154 System.out.print(ccbdate.getUser1_name()+"在中国建设银行的"+AtmNumber+"号ATM机上取款¥"); 155 System.out.printf("%.2f\n",Money); 156 System.out.printf("当前余额为¥%.2f\n",ccbdate.getUser1_CardMoney()); 157 } 158 } 159 else 160 if(Money<=0) 161 { 162 ccbdate.setUser1_CardMoney(ccbdate.getUser1_CardMoney()-Money); 163 System.out.print(ccbdate.getUser1_name()+"在中国建设银行的"+AtmNumber+"号ATM机上存款¥"); 164 System.out.printf("%.2f\n",-Money); 165 System.out.printf("当前余额为¥%.2f\n",ccbdate.getUser1_CardMoney()); 166 167 } 168 169 } 170 171 172 } 173 else { 174 System.out.println("Sorry,your password is wrong."); 175 System.exit(0); 176 } 177 178 } 179 else 180 if(icbcdate.checkValidate(CardNumber, icbcdate)) 181 { 182 183 if(Password.equals("88888888")) 184 { 185 atmicbc.Chackvalidate(AtmNumber); 186 187 if(CardNumber.equals(icbcdate.getUser0_CardNumber1())) 188 { 189 if(Money>0) 190 { 191 if(Money>icbcdate.getUser0_Card1Money()) 192 System.out.print("Sorry,your account balance is insufficient."); 193 else 194 { 195 icbcdate.setUser0_Card1Money(icbcdate.getUser0_Card1Money()-Money); 196 System.out.print(icbcdate.getUser0_name()+"在中国工商银行的"+AtmNumber+"号ATM机上取款¥"); 197 System.out.printf("%.2f\n",Money); 198 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser0_Card1Money()); 199 } 200 } 201 else 202 if(Money<=0) 203 { 204 icbcdate.setUser0_Card1Money(icbcdate.getUser0_Card1Money()-Money); 205 System.out.print(icbcdate.getUser0_name()+"在中国工商银行的"+AtmNumber+"号ATM机上存款¥"); 206 System.out.printf("%.2f\n",-Money); 207 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser0_Card1Money()); 208 209 } 210 211 212 213 } 214 if(CardNumber.equals(icbcdate.getUser0_CardNumber2())) 215 { 216 if(Money>0) 217 { 218 if(Money>icbcdate.getUser0_Card2Money()) 219 System.out.print("Sorry,your account balance is insufficient."); 220 else 221 { 222 icbcdate.setUser0_Card2Money(icbcdate.getUser0_Card2Money()-Money); 223 System.out.print(icbcdate.getUser0_name()+"在中国工商银行的"+AtmNumber+"号ATM机上取款¥"); 224 System.out.printf("%.2f\n",Money); 225 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser0_Card2Money()); 226 } 227 } 228 else 229 if(Money<=0) 230 { 231 icbcdate.setUser0_Card2Money(icbcdate.getUser0_Card2Money()-Money); 232 System.out.print(icbcdate.getUser0_name()+"在中国工商银行的"+AtmNumber+"号ATM机上存款¥"); 233 System.out.printf("%.2f\n",-Money); 234 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser0_Card2Money()); 235 236 } 237 238 239 240 241 242 243 } 244 if(CardNumber.equals(icbcdate.getUser0_CardNumber01())||CardNumber.equals(icbcdate.getUser0_CardNumber02())) 245 { 246 if(Money>0) 247 { 248 if(Money>icbcdate.getUser0_Card3Money()) 249 System.out.print("Sorry,your account balance is insufficient."); 250 else 251 { 252 icbcdate.setUser0_Card3Money(icbcdate.getUser0_Card3Money()-Money); 253 System.out.print(icbcdate.getUser0_name()+"在中国工商银行的"+AtmNumber+"号ATM机上取款¥"); 254 System.out.printf("%.2f\n",Money); 255 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser0_Card3Money()); 256 } 257 } 258 else 259 if(Money<=0) 260 { 261 icbcdate.setUser0_Card3Money(icbcdate.getUser0_Card3Money()-Money); 262 System.out.print(icbcdate.getUser0_name()+"在中国工商银行的"+AtmNumber+"号ATM机上存款¥"); 263 System.out.printf("%.2f\n",-Money); 264 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser0_Card3Money()); 265 266 } 267 268 269 270 } 271 if(CardNumber.equals(icbcdate.getUser1_CardNumber1())) 272 { 273 if(Money>0) 274 { 275 if(Money>icbcdate.getUser1_Card1Money()) 276 System.out.print("Sorry,your account balance is insufficient."); 277 else 278 { 279 icbcdate.setUser1_Card1Money(icbcdate.getUser1_Card1Money()-Money); 280 System.out.print(icbcdate.getUser1_name()+"在中国工商银行的"+AtmNumber+"号ATM机上取款¥"); 281 System.out.printf("%.2f\n",Money); 282 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser1_Card1Money()); 283 } 284 } 285 else 286 if(Money<=0) 287 { 288 icbcdate.setUser1_Card1Money(icbcdate.getUser1_Card1Money()-Money); 289 System.out.print(icbcdate.getUser1_name()+"在中国工商银行的"+AtmNumber+"号ATM机上存款¥"); 290 System.out.printf("%.2f\n",-Money); 291 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser1_Card1Money()); 292 293 } 294 295 296 297 298 } 299 if(CardNumber.equals(icbcdate.getUser1_CardNumber2())) 300 { 301 if(Money>0) 302 { 303 if(Money>icbcdate.getUser1_Card2Money()) 304 System.out.print("Sorry,your account balance is insufficient."); 305 else 306 { 307 icbcdate.setUser1_Card2Money(icbcdate.getUser1_Card2Money()-Money); 308 System.out.print(icbcdate.getUser1_name()+"在中国工商银行的"+AtmNumber+"号ATM机上取款¥"); 309 System.out.printf("%.2f\n",Money); 310 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser1_Card2Money()); 311 } 312 } 313 else 314 if(Money<=0) 315 { 316 icbcdate.setUser1_Card2Money(icbcdate.getUser1_Card2Money()-Money); 317 System.out.print(icbcdate.getUser1_name()+"在中国工商银行的"+AtmNumber+"号ATM机上存款¥"); 318 System.out.printf("%.2f\n",-Money); 319 System.out.printf("当前余额为¥%.2f\n",icbcdate.getUser1_Card2Money()); 320 321 } 322 323 } 324 325 326 } 327 else { 328 System.out.println("Sorry,your password is wrong."); 329 System.exit(0); 330 } 331 332 } 333 else { 334 System.out.println("Sorry,this card does not exist."); 335 System.exit(0); 336 } 337 338 339 340 } 341 342 343 344 } 345 } 346 347 } 348 349 class CCBDate { 350 private String user0_name = "杨过"; 351 private String user1_name = "郭靖"; 352 private String user0_CardNumber01 = "6217000010041315709"; 353 private String user0_CardNumber02 = "6217000010041315715"; 354 private String user0_CardNumber1 = "6217000010041315718"; 355 private String user1_CardNumber1 = "6217000010051320007"; 356 private float user0_Card1Money = (float) 10000.00; 357 private float user0_Card2Money = (float) 10000.00; 358 private float user1_CardMoney = (float) 10000.00; 359 public String getUser0_name() { 360 return user0_name; 361 } 362 public void setUser0_name(String user0_name) { 363 this.user0_name = user0_name; 364 } 365 public String getUser1_name() { 366 return user1_name; 367 } 368 public void setUser1_name(String user1_name) { 369 this.user1_name = user1_name; 370 } 371 public String getUser0_CardNumber01() { 372 return user0_CardNumber01; 373 } 374 public void setUser0_CardNumber01(String user0_CardNumber01) { 375 this.user0_CardNumber01 = user0_CardNumber01; 376 } 377 public String getUser0_CardNumber02() { 378 return user0_CardNumber02; 379 } 380 public void setUser0_CardNumber02(String user0_CardNumber02) { 381 this.user0_CardNumber02 = user0_CardNumber02; 382 } 383 public String getUser0_CardNumber1() { 384 return user0_CardNumber1; 385 } 386 public void setUser0_CardNumber1(String user0_CardNumber1) { 387 this.user0_CardNumber1 = user0_CardNumber1; 388 } 389 public String getUser1_CardNumber1() { 390 return user1_CardNumber1; 391 } 392 public void setUser1_CardNumber1(String user1_CardNumber1) { 393 this.user1_CardNumber1 = user1_CardNumber1; 394 } 395 public float getUser0_Card1Money() { 396 return user0_Card1Money; 397 } 398 public void setUser0_Card1Money(float user0_Card1Money) { 399 this.user0_Card1Money = user0_Card1Money; 400 } 401 public float getUser0_Card2Money() { 402 return user0_Card2Money; 403 } 404 public void setUser0_Card2Money(float user0_Card2Money) { 405 this.user0_Card2Money = user0_Card2Money; 406 } 407 public float getUser1_CardMoney() { 408 return user1_CardMoney; 409 } 410 public void setUser1_CardMoney(float user1_CardMoney) { 411 this.user1_CardMoney = user1_CardMoney; 412 } 413 public boolean checkValidate(String CardNumber,CCBDate ccbdate) 414 { 415 if(CardNumber.equals(ccbdate.getUser0_CardNumber01())||CardNumber.equals(ccbdate.getUser0_CardNumber02())||CardNumber.equals(ccbdate.getUser0_CardNumber1())||CardNumber.equals(ccbdate.getUser1_CardNumber1())) 416 { 417 return true; 418 } 419 else 420 return false; 421 } 422 423 424 } 425 class ICBCDate { 426 private String user0_name = "张无忌"; 427 private String user1_name = "韦小宝"; 428 private String user0_CardNumber1 = "6222081502001312389"; 429 private String user0_CardNumber2 = "6222081502001312390"; 430 private String user0_CardNumber01 = "6222081502001312399"; 431 private String user0_CardNumber02 = "6222081502001312400"; 432 private String user1_CardNumber1 = "6222081502051320785"; 433 private String user1_CardNumber2 = "6222081502051320786"; 434 private float user0_Card1Money = (float) 10000.00; 435 private float user0_Card2Money = (float) 10000.00; 436 private float user0_Card3Money = (float) 10000.00; 437 private float user1_Card1Money = (float) 10000.00; 438 private float user1_Card2Money = (float) 10000.00; 439 public String getUser0_CardNumber02() { 440 return user0_CardNumber02; 441 } 442 443 public void setUser0_CardNumber02(String user0_CardNumber02) { 444 this.user0_CardNumber02 = user0_CardNumber02; 445 } 446 447 public String getUser1_CardNumber1() { 448 return user1_CardNumber1; 449 } 450 451 public void setUser1_CardNumber1(String user1_CardNumber1) { 452 this.user1_CardNumber1 = user1_CardNumber1; 453 } 454 455 public String getUser1_CardNumber2() { 456 return user1_CardNumber2; 457 } 458 459 public void setUser1_CardNumber2(String user1_CardNumber2) { 460 this.user1_CardNumber2 = user1_CardNumber2; 461 } 462 463 public String getUser0_name() { 464 return user0_name; 465 } 466 467 public void setUser0_name(String user0_name) { 468 this.user0_name = user0_name; 469 } 470 471 public String getUser1_name() { 472 return user1_name; 473 } 474 475 public void setUser1_name(String user1_name) { 476 this.user1_name = user1_name; 477 } 478 479 public String getUser0_CardNumber1() { 480 return user0_CardNumber1; 481 } 482 483 public void setUser0_CardNumber1(String user0_CardNumber1) { 484 this.user0_CardNumber1 = user0_CardNumber1; 485 } 486 487 public String getUser0_CardNumber2() { 488 return user0_CardNumber2; 489 } 490 491 public void setUser0_CardNumber2(String user0_CardNumber2) { 492 this.user0_CardNumber2 = user0_CardNumber2; 493 } 494 495 public String getUser0_CardNumber01() { 496 return user0_CardNumber01; 497 } 498 499 public void setUser0_CardNumber01(String user0_CardNumber01) { 500 this.user0_CardNumber01 = user0_CardNumber01; 501 } 502 public float getUser0_Card1Money() { 503 return user0_Card1Money; 504 } 505 506 public void setUser0_Card1Money(float user0_Card1Money) { 507 this.user0_Card1Money = user0_Card1Money; 508 } 509 510 public float getUser0_Card2Money() { 511 return user0_Card2Money; 512 } 513 514 public void setUser0_Card2Money(float user0_Card2Money) { 515 this.user0_Card2Money = user0_Card2Money; 516 } 517 518 public float getUser0_Card3Money() { 519 return user0_Card3Money; 520 } 521 522 public void setUser0_Card3Money(float user0_Card3Money) { 523 this.user0_Card3Money = user0_Card3Money; 524 } 525 526 public float getUser1_Card1Money() { 527 return user1_Card1Money; 528 } 529 530 public void setUser1_Card1Money(float user1_Card1Money) { 531 this.user1_Card1Money = user1_Card1Money; 532 } 533 534 public float getUser1_Card2Money() { 535 return user1_Card2Money; 536 } 537 538 public void setUser1_Card2Money(float user1_Card2Money) { 539 this.user1_Card2Money = user1_Card2Money; 540 } 541 public boolean checkValidate(String CardNumber,ICBCDate icbcdate) { 542 if(CardNumber.equals(icbcdate.getUser0_CardNumber01())||CardNumber.equals(icbcdate.getUser0_CardNumber02())||CardNumber.equals(icbcdate.getUser0_CardNumber1())||CardNumber.equals(icbcdate.getUser0_CardNumber2())||CardNumber.equals(icbcdate.getUser1_CardNumber1())||CardNumber.equals(icbcdate.getUser1_CardNumber2())) 543 { 544 return true; 545 } 546 else 547 return false; 548 } 549 550 } 551 class atmCCB { 552 public void Chackvalidate(String AtmNumber) { 553 if(!AtmNumber.equals("01")&&!AtmNumber.equals("02")&&!AtmNumber.equals("03")&&!AtmNumber.equals("04")) 554 { 555 if(AtmNumber.equals("05")||AtmNumber.equals("06")) 556 { 557 System.out.println("Sorry,cross-bank withdrawal is not supported."); 558 System.exit(0); 559 } 560 else 561 { 562 System.out.println("Sorry,the ATM's id is wrong."); 563 System.exit(0); 564 } 565 } 566 567 } 568 } 569 class atmICBC { 570 public void Chackvalidate(String AtmNumber) { 571 if(!AtmNumber.equals("05")&&!AtmNumber.equals("06")) 572 { 573 if(AtmNumber.equals("01")||AtmNumber.equals("02")||AtmNumber.equals("03")||AtmNumber.equals("04")) 574 { 575 System.out.println("Sorry,cross-bank withdrawal is not supported."); 576 System.exit(0); 577 } 578 else { 579 System.out.println("Sorry,the ATM's id is wrong."); 580 System.exit(0); 581 } 582 } 583 584 } 585 }
分析：本题解答比较复杂，主要是理解题目意思，每个人对类的设计都有不同，可尝试换一种方式来解题，可以使用Java数据库来解题并运用Java的继承与多态来减少重复的代码
总结：
这次题目集的完成，是一个从易到难的过程，从开始的点线基础到面相关的运用，以点及线，以线到面的过程，是自我编程能力不断提升，从这题
目集的练习我熟悉了正确运用循环及条件来控制程序，如何正确判断输入的边界值，对数值进行判断与处理，以及如何运用Java的多态与继承来提
高代码的复用性以及代码的可拓展性来简化一些题目的流程，使其条理清晰，更通俗易懂；面对一些复杂的问题时如何将其程序化，数字化，用面
向对象的思维来思考问题，处理问题，解决问题；同时也发现了自己的写程序方面的一些不足之处，编写速度，代码的算法的优越性等等，在这些
方面，我还应该加强。同时对教师、课程、作业、实验、课上及课下组织方式等方面，我觉得十分合理，老师这么做一定有他的道理，为了帮助我
们更好的学习专业知识等等。
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