图书馆借阅系统「建议收藏」

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图书馆借阅系统
一、图书馆借阅系统是对书籍信息操作的信息管理系统。书籍信息包括书名、作者、编号、是否借出。本系统针对两类用户（图书管理员和学生）使用，对于图书馆管理员，可以进行查看书籍列表、查找书籍、新增书籍信息、删除书籍、退出登录操作；对于学生，可以进行查看书籍列表、查找书籍、借阅书籍、归还书籍、退出登录操作。

二、代码部分
1.book包的建立
Book类的建立对于图书馆借阅系统，把书看作一个对象，根据该book所具有的属性，定义一系列书籍的私有属性，以及对这些属性进行操作的访问器（get()）和设置器（set（））。

package book;
public class Book { 
   
	private String name;// 书名
	private String author;// 书的作者
	private int num;// 书的编号
	private boolean flag;// 判断书是否被借出去了 
 public Book(String name, String author, int num) { 
                   
        this.name = name; 
        this.author = author;      
        this.num = num;    
        }    
 public String getName() { 
          
       return name;  
    }   
 public String getAuthor() { 
           
       return author; 
    }   
 public int getNum() { 
           
        return num;  
          }        
 public void setFlag(boolean borrowed) { 
         
          flag = borrowed;   
           }   
 public boolean getFlag() { 
           
           return flag;   
            }    
 public String toString() { 
          
             return "name:" + name + " author:" + author + " num:" + num +" "+ (flag ? "已经借出" : "未借出");    
             }
}

Booklist类的建立
Booklist类中的数组用来存放书籍信息，以及针对Booklist类完成增删改等相关操作。

package book;
public class Booklist { 
   
	public Book books[];
	private int number;
public Booklist() { 
           
this.books = new Book[20];        
this.books[0] = new Book("Java语言基础教程", "李东明、张丽娟", 1);       
 this.books[1] = new Book("C程序设计", "谭浩强", 2);        this.books[2] = new Book("高等数学I", "同济", 3);        this.books[3] = new Book("高等数学II", "同济", 4);        this.books[4] = new Book("数据结构", "严蔚敏", 5);        this.number = 5;    
 }    
 public void setBook(int b, Book book) { 
           
 books[b] = book;    
 }    
 public Book getBook(int b) { 
           return books[b];    }        public void setNumber(int n) { 
           number = n;    }    
 public int getNumber( ) { 
           return number;    }
}

2.operation包的建立
Operation类的建立①这是所有的操作（查找，增加，删除，借阅，归还，退出）共同的接口；②需要一个oper（）方法，这个方法针对Booklist类进行操作。

package operation;
import book.Booklist;//接口
public interface Operation { 
   
	void oper(Booklist booklist);
}

查找书籍信息（根据书名或者编号）
选择相应的查找功能，根据你输入的name或者number进行查找。

package operation;
import java.util.Scanner;
import book.Booklist;//查找书籍
public class Find implements Operation { 
       
public void oper(Booklist booklist) { 
          
         int i;      
         Scanner reader = new Scanner(System.in);                        System.out.println("请输入您需要寻找的书名：");              String name = reader.next();       
          for (i = 0; i < booklist.getNumber(); i++) { 
   
    //System.out.println(booklist.getBook(i).getName().equals(name)); 
         if (booklist.getBook(i).getName().equals(name)) { 
                                           System.out.println("找到您所需要的书："+booklist.books[i]);                
         return;          
           }	    
}      
if (i >= booklist.getNumber()) { 
               System.out.println("抱歉！未找到您需要的书！");      
  }    
  }
}

package operation;
import java.util.Scanner;
import book.Booklist;根据编号查找书籍
public class Find1 implements Operation{ 
   
	public void oper(Booklist booklist) { 
   
			int i;
			Scanner reader = new Scanner(System.in);        
			System.out.println("请输入您需要寻找的书的编号：");        
			int number = reader.nextInt();        
			for (i = 0; i < booklist.getNumber(); i++) { 
           //System.out.println(booklist.getBook(i).getNum()==number); 
                           if (booklist.getBook(i).getNum()==number){ 
                              System.out.println("找到您所需要的书："+booklist.books[i]);             
                               return;          
                               }
                      }      
                      if (i >= booklist.getNumber()) { 
            
                       		System.out.println("抱歉！未找到您需要的书！");      }
               	}
}

增加书籍
在主函数界面输入新的书的信息，将这些信息赋值于Book类相应的信息，并将书插入Booklist类的books数组中。

package operation;import java.util.Scanner;import book.Book;import book.Booklist;//增加书籍
public class Add implements Operation { 
       public void oper(Booklist booklist) { 
           
Scanner reader = new Scanner(System.in);        System.out.println("请输入需要添加的书籍：");        
String name = reader.nextLine();        System.out.println("请输入书籍的作者：");      
  String author = reader.nextLine();        System.out.println("请输入书籍的编号：");       
   int num = reader.nextInt();        
   Book book = new Book(name, author, num);     
      int a = booklist.getNumber();      
        booklist.setBook(a, book);        
        booklist.setNumber(a + 1);       
         System.out.println("成功增加"+name+"书籍!");  
           }
           }

删除书籍（根据书名或者编号）

package operation;import java.util.Scanner;import book.Book;import book.Booklist;//删除书籍
public class Delete implements Operation { 
      
 public void oper(Booklist booklist) { 
           System.out.println("请输入您需要删除的书籍：");        Scanner reader = new Scanner(System.in);       
  String name = reader.nextLine();       
   int de = booklist.getNumber();      
     int b = 0;        
     for (int i = 0; i < booklist.getNumber(); i++) { 
              
      Book book = booklist.getBook(i);        
          if (book.getName().equals(name)) { 
              
               b = i;  
               break;          
                 }        
                 }        
                 for (int j = b; j < de - 1; j++) { 
               booklist.setBook(j, booklist.getBook(j + 1));    
                     }       
                      booklist.setNumber(de - 1);        System.out.println("成功删除书籍！");  
                        }
                        }

package operation;import java.util.Scanner;import book.Book;import book.Booklist;//根据编号删除书籍
public class Delete1 implements Operation{ 
   	
public void oper(Booklist booklist) { 
   
		System.out.println("请输入您需要删除的书籍：");        Scanner reader = new Scanner(System.in);  
		      int number = reader.nextInt();      
		        int de = booklist.getNumber();      
		          int i;        
		          for (i = 0; i < booklist.getNumber(); i++) { 
         
		            	Book book = booklist.getBook(i);           
		            	 if (book.getNum()==number) { 
                 
		            	 break;         
		            	    }        
		            	 }        
		            	  if(i>booklist.getNumber()) { 
          
		            	   	return ;       
		            	   	 }        
	Book book1=booklist.getBook(de-1);        
	booklist.setBook(i, book1);        
	booklist.setNumber(de-1);        
	System.out.println("成功删除书籍！");	
	}
	}

借阅书籍(根据书名或者编号)

package operation;import java.util.Scanner;import book.Book;import book.Booklist;//借阅书籍
public class Borrow implements Operation { 
      
 public void oper(Booklist booklist) { 
           
 Scanner reader = new Scanner(System.in);        System.out.println("请输入您需要借阅的书籍：");        String name = reader.next();      
   int i;     
      for (i = 0; i < booklist.getNumber(); i++) { 
      
           	Book book = booklist.getBook(i);        
           	    if (booklist.getBook(i).getName().equals(name)) { 
                   if (book.getFlag()) { 
                      
           	     System.out.println("抱歉！此书籍"+book.getName()+"已经被借阅！");            
           	         }
           	          else { 
                     
           	            book.setFlag(true);                    System.out.println("成功借阅书籍"+book.getName()+"！");                    
           	            break;                
           	            }           
           	             }      
           	               }    }}

package operation;import java.util.Scanner;import book.Book;import book.Booklist;
public class Borrow1 implements Operation{ 
   
	public void oper(Booklist booklist) { 
   
			Scanner reader = new Scanner(System.in);        System.out.println("请输入您需要借阅的书籍的编号：");        int number = reader.nextInt();      
			  int i;        
			  for (i = 0; i < booklist.getNumber(); i++) { 
     
			        	Book book = booklist.getBook(i);        
			        	    if (book.getNum()==number) { 
                   if (book.getFlag()) { 
                       
			        	    System.out.println("抱歉！此书籍"+book.getName()+"已经被借阅！");             
			        	       }
			        	     else { 
                       
			        	     book.setFlag(true);                    
			        	     System.out.println("成功借阅书籍"+book.getName()+"！");                  
			        	       break;                
			        	       }            }        }	}}

归还书籍(根据书名或者编号)

package operation;import java.util.Scanner;import book.Book;import book.Booklist;//归还书籍
public class Return implements Operation { 
      
 public void oper(Booklist booklist) { 
           
 Scanner reader = new Scanner(System.in);        
 System.out.println("请输入您需要归还的书籍：");        
 String name = reader.nextLine();       
  for (int i = 0; i < booklist.getNumber(); i++) { 
             
    Book book = booklist.getBook(i);            
    if (book.getName().equals(name)) { 
       
                System.out.println("成功归还书籍！");          
                  }          
                    book.setFlag(false);        }    }}

package operation;import java.util.Scanner;import book.Book;import book.Booklist;
public class Return1 implements Operation{ 
   
	public void oper(Booklist booklist) { 
   
			Scanner reader = new Scanner(System.in);        
			System.out.println("请输入您需要归还的书籍：");       
			 int number = reader.nextInt();        
			 for (int i = 0; i < booklist.getNumber(); i++) { 
   
			             Book book = booklist.getBook(i);           
			  if (book.getNum()==number) { 
                   
			  System.out.println("成功归还书籍！");         
			     }           
			      book.setFlag(false);        }	}}

退出系统

package operation;import book.Booklist;
public class Exit implements Operation { 
       
public void oper(Booklist booklist) { 
       
	System.out.println("谢谢使用图书馆系统!");        System.exit(0);//正常运行程序并退出程序
	    }}

3.user包的建立
本系统针对两类用户使用(管理员和学生)
用户(抽象类)

package users;import book.Booklist;import operation.Operation;
public abstract class User { 
   	
    public String name;	  
      public Operation operations[];	    
      public User(String name) { 
   
      	        this.name = name;
      	        	    }
      public abstract int meanu();	    
      public void opera(int choice, Booklist booklist) { 
   	
              operations[choice].oper(booklist);	  
                }}

管理员

package users;import java.util.Scanner;import operation.Add;import operation.Delete;import operation.Delete1;import operation.Display;import operation.Exit;import operation.Find;import operation.Find1;import operation.Operation;//管理员
public class Administrator extends User { 
       
public int meanu() { 
          
 Scanner reader = new Scanner(System.in);        
 System.out.println("\t-----------------------------------");        
 System.out.println("\t\t********0.书籍列表********");        
 System.out.println("\t********1.查找书籍(根据书名)********");       
  System.out.println("\t********2.查找书籍(根据编号)********");       
   System.out.println("\t\t********3.增加书籍********");        
   System.out.println("\t********4.删除书籍(根据书名)********");      
     System.out.println("\t********5.删除书籍(根据编号)********");       
      System.out.println("\t\t********6.退出登录********");       
       System.out.println("\t-----------------------------------");       
        int choice = reader.nextInt();        
        return choice;   
         }   
          public Administrator(String name) { 
           
          super(name);       
           this.operations = new Operation[] { 
    new Display(), new Find(),new Find1(), new Add(), new Delete(),new Delete1(), new Exit() };    
           }}

学生

package users;import java.util.Scanner;import operation.Borrow;import operation.Borrow1;import operation.Display;import operation.Exit;import operation.Find;import operation.Find1;import operation.Operation;import operation.Return;import operation.Return1;//学生
public class Student extends User { 
    
public int meanu() { 
        
Scanner reader = new Scanner(System.in);        
System.out.println("\t-----------------------------------");        
System.out.println("\t\t********0.书籍列表********");        
System.out.println("\t********1.查找书籍(根据书名)********");        
System.out.println("\t********2.查找书籍(根据编号)********");        
System.out.println("\t********3.借阅书籍(根据书名)********");      
System.out.println("\t********4.借阅书籍(根据编号)********");        
System.out.println("\t********5.归还书籍(根据书名)********");       
System.out.println("\t********6.归还书籍(根据编号)********");        
System.out.println("\t\t********7.退出登录********");        
System.out.println("\t-----------------------------------");        
int choice = reader.nextInt();        
return choice;    }   
public Student(String name) { 
        
super(name);        
this.operations = new Operation[] { 
 new Display(), new Find(),new Find1(), new Borrow(),new Borrow1(), new Return(),new Return1(), new Exit() };    
}}

4.Main类的建立
在Main类中有一个系统入口的主函数界面，在这个界面里，通过输入的功能号选择用户想要实现的功能，这个主函数的相应功能的实现通过与operation包内的类的方法进行交互。

package main;import java.util.Scanner;import book.Booklist;import users.Administrator;import users.Student;import users.User;//登录界面
class Enter { 
  
private static String password = "1234567";//设置密码为123456 
private static String password1 = "123456";//设置密码为123456 
public static User login() { 
       
Scanner reader = new Scanner(System.in);        
System.out.println("********登录********");        
System.out.println("请输入用户名:");        
String name = reader.nextLine();                //管理员登录 
if ("administrator".equals(name)) { 
            
System.out.println("请输入密码:");                     
if (reader.next().equals(password)) { 
                
System.out.println("欢迎使用图书馆借阅系统!");                
User Administrator = new Administrator(name);                
return Administrator;            
} 
else { 
              
System.out.println("密码错误！请重新输入密码!");            }        }                //学生登录 
if ("student".equals(name)) { 
            
System.out.println("请输入密码:");              
if (reader.next().equals(password1)) { 
                
System.out.println("欢迎使用图书馆借阅系统!");                
User Student = new Student(name);                
return Student;        
} 
else { 
              
System.out.println("密码错误！请重新输入密码!");            }       
}        
return null;    }}
public class Main { 
    
public static void main(String args[]) { 
        
Booklist booklist = new Booklist();        
User user = Enter.login();       
while (true) { 
           
int choice = user.meanu();           
user.opera(choice, booklist);    
}    
}}