}
		return 0;
	}
	//查詢某圖書所屬分類的最大借閱天數,由類BorrowBook調用
	public static int selectKeepDaysofBook(int id){
		String sql="select days from tb_bookType where id="+id;
		ResultSet rs=Dbo.executeQuery(sql);
		try{
			if(rs.next()){
				return rs.getInt("days");
			}
			else return 0;
		}catch(Exception e){
			e.printStackTrace();
			return 0;
		}
	}
	//為禁止管理員重復添加讀者借書信息的方法而設計的查詢方法，由類BorrowBook調用
	public  static int selectHasBorrowed(String readerId,String ISBN){
		String sql="select * from tb_borrow where readerid='"+readerId+"' AND bookISBN='"+ISBN+"'";
		ResultSet rs=Dbo.executeQuery(sql);
		try{
			if(rs.next()){
				return 1;
			}
			else return 0;
		}catch(Exception e){
			e.printStackTrace();
			return 1;
		}
	}
	//查詢指定圖書類別的詳細信息，由類MoifyAndDelBook調用
	public static BookType selectDetailBookType(String typeName){
		String sql="select * from tb_bookType where typeName='"+typeName+"'";
		ResultSet rs=Dbo.executeQuery(sql);
		try{
			BookType bookType=new BookType();
			if(rs.next()){
				bookType.setTypeName(rs.getString("typeName"));
				bookType.setFk(rs.getInt("fk"));
				bookType.setExpired(rs.getInt("expire"));
				bookType.setDays(rs.getInt("days"));
				bookType.setId(rs.getInt("id"));
				return bookType;
			}
		}catch(Exception e){
				e.printStackTrace();
				return null;
		}
		return null;
	}
	//查詢所有圖書類別的信息，用于顯示所有圖書類別信息，由雷ModifyAndDelBook調用
	public static ArrayList selectAllBookType(){
		String sql="select * from tb_bookType";
		ResultSet rs=Dbo.executeQuery(sql);
		ArrayList arrayList=new ArrayList();
		try{
			while(rs.next()){
				BookType bookType=new BookType();
				bookType.setDays(rs.getInt("days"));
				bookType.setExpired(rs.getInt("expire"));
				bookType.setFk(rs.getInt("fk"));
				bookType.setId(rs.getInt("id"));
				bookType.setTypeName(rs.getString("typeName"));
				arrayList.add(bookType);
			}
			Dbo.close();
			return arrayList;
		}catch(Exception e){
			e.printStackTrace();
			return null; 
		}
	}
	//查詢指定ID的讀者類型的方法，由類ModifyAndDelReader
	public static ReaderType selectSelectedReaderType(int id){
		String sql="select * from tb_readerType where typeId="+id;
		ResultSet rs=Dbo.executeQuery(sql);
		try{
			if(rs.next()){
				ReaderType readerType=new ReaderType();
				readerType.setMaxBorrowNumber(rs.getInt("maxBorrowNumber"));
				readerType.setmaxKeepDays(rs.getInt("maxKeepDays"));
				readerType.setTypeId(id);
				readerType.setTypeName(rs.getString("typeName"));
				Dbo.close();
				return readerType;
			}
		}catch(Exception e){
			e.printStackTrace();
			return null;
		}
		return null;
	}
	//按照指定的讀者類型名稱查詢讀者類型,由類ModifyAndDelReaderType
	public static ReaderType selectDetailReaderType(String typeName){
		String sql="select * from tb_readerType where typeName='"+typeName+"'";
		ResultSet rs=Dbo.executeQuery(sql);
		try{
			if(rs.next()){
				ReaderType readerType=new ReaderType();
				readerType.setTypeName(typeName);
				readerType.setTypeId(rs.getInt("typeId"));
				readerType.setMaxBorrowNumber(rs.getInt("maxBorrowNumber"));
				readerType.setmaxKeepDays(rs.getInt("maxKeepDays"));
				return readerType;
			}
		}catch(Exception e){
			e.printStackTrace();
			return null;
		}
		return null;
	}
	//查詢所有圖書管理員,有類ModiftDelUser調用
	public static ArrayList selectAllBookAdmin(){
		String sql="select * from tb_operator where admin=0";
		ResultSet rs=Dbo.executeQuery(sql);
		ArrayList arrayList=new ArrayList();
		try{
			while(rs.next()){
				Operator operator=new Operator();
				operator.setName(rs.getString("name"));
				operator.setId(rs.getInt("operatorId"));
				operator.setIdentityCardNumber(rs.getString("identityCard"));
				operator.setSex(rs.getString("sex"));
				operator.setTel(rs.getString("tel"));				
				operator.setWorkDate(rs.getString("workdate"));
				operator.setPassword(rs.getString("password"));
				arrayList.add(operator);
			}
			return arrayList;
		}catch(Exception e){
			e.printStackTrace();
			return null;
		}
	}
	//判斷是否要修改的管理員是否與現有管理員重名的方法，由類ModifyDelUser調用
	public static String selectSpecifiedOperatorName(String name,int id){
		String sql="select name from tb_operator where name='"+name+"' And operatorId!="+id;
		ResultSet rs=Dbo.executeQuery(sql);
		try {
			if(rs.next())
				return rs.getString("name");
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
		return null;
	}
	//查詢某管理員密碼的方法，由類ModifyPassword調用
	public static String selectAdminPassword(int id){
		String sql="select password from tb_operator where operatorID="+id;
		ResultSet rs=Dbo.executeQuery(sql);
		try {
			if(rs.next())
				return rs.getString(1);
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
		return null;
	}
	//按照圖書名稱查找相應圖書的方法，有類SearchBook調用
	public static ArrayList selectSpecifiedBook(String name){
		String sql="select * from tb_bookInfo where bookname like '%"+name+"%'";
		ResultSet rs=Dbo.executeQuery(sql);
		ArrayList arrayList=new ArrayList();
		try {
			while(rs.next()){
				Book book=new Book();
				book.setBookname(rs.getString("bookname"));
				book.setDate(rs.getString("date"));
				book.setISBN(rs.getString("ISBN"));
				book.setPrice(rs.getFloat("price"));
				book.setPublisher(rs.getString("publisher"));
				book.setTranslator(rs.getString("translator"));
				book.setWriter(rs.getString("writer"));
				arrayList.add(book);
			}
			return arrayList;
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
	}
	//按照圖書作者查找相應圖書的方法，有類SearchBook調用
	public static ArrayList selectSpecifiedWriterBook(String writer){
		String sql="select * from tb_bookInfo where writer like '%"+writer+"%'";
		ResultSet rs=Dbo.executeQuery(sql);
		ArrayList arrayList=new ArrayList();
		try {
			while(rs.next()){
				Book book=new Book();
				book.setBookname(rs.getString("bookname"));
				book.setDate(rs.getString("date"));
				book.setISBN(rs.getString("ISBN"));
				book.setPrice(rs.getFloat("price"));
				book.setPublisher(rs.getString("publisher"));
				book.setTranslator(rs.getString("translator"));
				book.setWriter(rs.getString("writer"));
				arrayList.add(book);
			}
			return arrayList;
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
	}
	//查詢指定圖書編號的圖書信息，由類SearchBook調用
	public static Book selectSpecifiedISBNBook(String ISBN){
		String sql="select * from tb_bookinfo where ISBN='"+ISBN+"'";
		ResultSet rs=Dbo.executeQuery(sql);
		try {
			if(rs.next()){
				Book book=new Book();
				book.setBookname(rs.getString("bookname"));
				book.setDate(rs.getString("date"));
				book.setISBN(rs.getString("ISBN"));
				book.setPrice(rs.getFloat("price"));
				book.setPublisher(rs.getString("publisher"));
				book.setTranslator(rs.getString("translator"));
				book.setWriter(rs.getString("writer"));
				return book;
			}
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
		return null;
	}
	//顯示所有圖書信息，由類SearchBook調用
	public static ArrayList selectAllBook(){
		String sql="select * from tb_bookinfo";
		ResultSet rs=Dbo.executeQuery(sql);
		ArrayList arrayList =new ArrayList();
		try {
			while(rs.next()){
				Book book=new Book();
				book.setBookname(rs.getString("bookname"));
				book.setDate(rs.getString("date"));
				book.setISBN(rs.getString("ISBN"));
				book.setPrice(rs.getFloat("price"));
				book.setPublisher(rs.getString("publisher"));
				book.setTranslator(rs.getString("translator"));
				book.setWriter(rs.getString("writer"));
				arrayList.add(book);
			}
			return arrayList;
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
	}
	//查找某讀者所借圖書的所有信息，由類ReturnBook調用
	public static ArrayList selectAllBorrowBook(String readerId){
		String sql="select * from tb_borrow where readerid='"+readerId+"'";
		ResultSet rs=Dbo.executeQuery(sql);
		ArrayList arrayList=new ArrayList();
		try {
			while(rs.next()){
				BorrowBookEntity borrowBookEntity=new BorrowBookEntity();
				borrowBookEntity.setBackDate(rs.getString("backDate"));
				borrowBookEntity.setBorrowDate(rs.getString("borrowDate"));
				borrowBookEntity.setISBN(rs.getString("bookISBN"));
				borrowBookEntity.setOperatorId(rs.getInt("operatorID"));
				borrowBookEntity.setReaderId(rs.getString("readerid"));
				arrayList.add(borrowBookEntity);
			}
			return arrayList;
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
	}
	//查詢指定讀者編號和指定書號的借閱信息由類ReturnBook調用
	public static BorrowBookEntity selectSpecifiedBorrowInfo(String readerId,String ISBN){
		String sql="select * from tb_borrow where readerid='"+readerId+"' and bookISBN='"+ISBN+"'";
		ResultSet rs=Dbo.executeQuery(sql);		
		try {
			if(rs.next()){
				BorrowBookEntity borrowBookEntity=new BorrowBookEntity();
				borrowBookEntity.setBackDate(rs.getString("backDate"));
				borrowBookEntity.setBorrowDate(rs.getString("borrowDate"));
				borrowBookEntity.setISBN(rs.getString("bookISBN"));
				borrowBookEntity.setOperatorId(rs.getInt("operatorID"));
				borrowBookEntity.setReaderId(rs.getString("readerid"));
				return borrowBookEntity;
			}
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
		return null;
	}
	//查詢指定書號是否已經在定書表中出現,由類OrdernewBook調用
	public static String selectNewBookISBN(String ISBN){
		String sql="select * from tb_order where ISBN='"+ISBN+"'";
		ResultSet rs=Dbo.executeQuery(sql);
		try {
			if(rs.next()){
				return rs.getString("ISBN");
			}
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		}
		return null;
	}
}