图书管理系统（增删改查带分页，上传）

首先要创建web项目，取名Book，创建分层，dao（impl），entuty，service，servlet，因为要用到分页，所以还有一个util；

创建分层之后，先写实体类，实体类包括下面这两张表的数据：

实体类对字符进行封装；

然后写basedao，就是连接数据库的工具类；

下一步就是创建bookdao接口的实现类，bookdaoimpl。bookdao接口中写要实现功能的方法，

在接口中 写入实现方法的sql语句：第一步，在页面查询出数据库中现有的数据：

public class BookDaoImpl extends BaseDao implements BookDao {@Testpublic void selectTest() throws Exception {}// 查询图书列表（分页）@Overridepublic List<Book> selectbook(int pageIndex, int pageSize) throws Exception {// 创建list集合存放book对象List<Book> list = new ArrayList<Book>();String sql = "select * from book limit ?,?";Object[] obj = { pageIndex, pageSize };ResultSet rs = executeSelect(sql, obj);if (rs != null) {while (rs.next()) {// 创建book对象Book book = new Book();book.setBookid(rs.getInt("bookid"));book.setBookname(rs.getString("bookname"));book.setBookpicture(rs.getString("bookpicture"));book.setBookprice(rs.getDouble("bookprice"));book.setBookabout(rs.getString("bookabout"));book.setBookauthor(rs.getString("bookauthor"));book.setBookcategory(rs.getInt("bookcategory"));book.setBookdatatime(rs.getDate("bookdatetime"));list.add(book);}}return list;}// 查询book表中的记录数@Overridepublic int getCount() throws Exception {int result = 0;String sql = "select count(*) as num from book";ResultSet rs = executeSelect(sql);if (rs != null) {if (rs.next()) {result = rs.getInt("num");}closeAll();}return result;}

// 按名称模糊查询（分页）

@Overridepublic List<Book> likebook(int category, String name,int pageIndex, int pageSize)throws Exception {// 创建list集合存放book对象List<Book> list = new ArrayList<Book>();StringBuffer sb=new StringBuffer("select * from book where 1=1");if(category!=0){sb=sb.append(" and bookcategory='"+category+"' ");}if(name!=""){sb=sb.append(" and bookname like '%"+name+"%'");}sb=sb.append(" limit ?,?");Object[] obj = { pageIndex, pageSize };ResultSet rs = executeSelect(sb.toString(), obj);if (rs != null) {while (rs.next()) {// 创建book对象Book book = new Book();book.setBookid(rs.getInt("bookid"));book.setBookname(rs.getString("bookname"));book.setBookpicture(rs.getString("bookpicture"));book.setBookprice(rs.getDouble("bookprice"));book.setBookabout(rs.getString("bookabout"));book.setBookauthor(rs.getString("bookauthor"));book.setBookcategory(rs.getInt("bookcategory"));book.setBookdatatime(rs.getDate("bookdatetime"));list.add(book);}}return list;}@Overridepublic int getselectCount(int category,String name) throws Exception {int result = 0;StringBuffer sb=new StringBuffer("select count(*) as num from book where 1=1 ");if(category!=0){sb=sb.append(" and bookcategory='"+category+"' ");}if(name!=""){sb=sb.append(" and bookname like '%"+name+"%'");}ResultSet rs = executeSelect(sb.toString());if (rs != null) {if (rs.next()) {result = rs.getInt("num");}closeAll();}return result;}@Overridepublic int deletebook(int id) throws Exception {String sql="delete from book where bookid='"+id+"'";int count = executeUpdate(sql);return count;}@Overridepublic Book uploadbook(int id) throws Exception {Book book=new Book();String sql="select * from book where bookid='"+id+"'";ResultSet rs = executeSelect(sql);if(rs!=null){if(rs.next()){book.setBookabout(rs.getString("bookabout"));book.setBookauthor(rs.getString("bookauthor"));book.setBookcategory(rs.getInt("bookcategory"));book.setBookdatatime(rs.getDate("bookdatetime"));book.setBookid(rs.getInt("bookid"));book.setBookname(rs.getString("bookname"));book.setBookpicture(rs.getString("bookpicture"));book.setBookprice(rs.getDouble("bookprice"));}}return book;}@Overridepublic List<BookCategory> selectcategory() throws Exception {List<BookCategory> list=new ArrayList<BookCategory>();String sql="select * from BookCategory";ResultSet rs = executeSelect(sql);if(rs!=null){while(rs.next()){BookCategory cate=new BookCategory();cate.setCateid(rs.getInt("cateid"));cate.setCatename(rs.getString("catename"));list.add(cate);}}return list;}//修改图书@Overridepublic int bookupdate(Book book,int id) throws Exception {String sql="update book set bookname=?,bookcategory=?,bookprice=?,bookauthor=?,bookabout=?,bookdatetime=?,bookpicture=? where bookid=?";Object[] obj={book.getBookname(),book.getBookcategory(),book.getBookprice(),book.getBookauthor(),book.getBookabout(),book.getBookdatatime(),book.getBookpicture(),id};int count = executeUpdate(sql, obj);return count;}//添加图书@Overridepublic int addbook(Book book) throws Exception {String sql="insert into book(bookname,bookcategory,bookprice,bookauthor,bookabout,bookdatetime,bookpicture) values(?,?,?,?,?,?,?)";Object [] obj={book.getBookname(),book.getBookcategory(),book.getBookprice(),book.getBookauthor(),book.getBookabout(),book.getBookdatatime(),book.getBookpicture()};int count = executeUpdate(sql, obj);return count;}}

service：

public interface BookService {//查询图书列表(分页)public List<Book> selectbook(int pageIndex,int pageSize) throws Exception;//查询Book表的记录数public int getCount() throws Exception;//按图书名称查询(分页)public List<Book> likebook(int category,String name,int pageIndex, int pageSize) throws Exception;//查询Book表的记录数public int getselectCount(int category,String name) throws Exception;//删除bookpublic int deletebook(int id) throws Exception;//修改bookpublic Book uploadbook(int id) throws Exception;//查询book分类public List<BookCategory> selectcategory() throws Exception;//修改图书public int bookupdate(Book book,int id) throws Exception;//添加图书public int addbook(Book book) throws Exception;}

service的实现类：

//创建BookDaoImpl对象，调用其方法
BookDao dao=new BookDaoImpl();
//查询图书带分页
@Override
public List<Book> selectbook(int pageIndex, int pageSize) throws Exception {
return dao.selectbook(pageIndex, pageSize);
}
//总记录数
@Override
public int getCount() throws Exception {
return dao.getCount();
}

@Override
public int deletebook(int id) throws Exception {
return dao.deletebook(id);
}
@Override
public Book uploadbook(int id) throws Exception {
return dao.uploadbook(id);
}
@Override
public List<BookCategory> selectcategory() throws Exception {
return dao.selectcategory();
}
@Override
public int bookupdate(Book book, int id) throws Exception {
return dao.bookupdate(book, id);
}
@Override
public int addbook(Book book) throws Exception {
return dao.addbook(book);
}
@Override
public List<Book> likebook(int category, String name, int pageIndex,
int pageSize) throws Exception {
return dao.likebook(category, name, pageIndex, pageSize);
}
@Override
public int getselectCount(int category, String name) throws Exception {
return dao.getselectCount(category, name);
}
}

最后就是servlet：

public class BookServlet extends HttpServlet {


public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {


doPost(request, response);
}


public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;charset=UTF-8");
response.setHeader("content-type", "text/html;charset=UTF-8");
// 创建Service对象
BookService service = new BookServiceImpl();


try {
List<BookCategory> catelists = service.selectcategory();
request.setAttribute("catelists", catelists);
} catch (Exception e1) {
e1.printStackTrace();
}
String action = request.getParameter("action");
Page pages = new Page();




// 默认显示三条数据
int pageSize = 3;
pages.setPageSize(pageSize);
// 当前页
int myIndex;
String pageIndex = request.getParameter("pageIndex");
if (pageIndex != null) {
myIndex = Integer.parseInt(pageIndex);
} else {
myIndex = 1;
}
pages.setPageIndex(myIndex);
String select=request.getParameter("select");

if(select!=null&&select!="")
{

System.out.println("=====================");
String selectname = request.getParameter("selectname");
String selectcate=request.getParameter("bookcategoryid");
int mytotal;
try {
int totalpage = service.getselectCount(Integer.parseInt(selectcate), selectname);
if (totalpage % pageSize == 0) {
mytotal = totalpage / pageSize;
} else {
mytotal = totalpage / pageSize + 1;
}
pages.setTotalPages(mytotal);
List<Book> likebook = service.likebook(Integer.parseInt(selectcate), selectname,(pages.getPageIndex() - 1)
* pages.getPageSize(), pages.getPageSize());
pages.setBooklist(likebook);
request.setAttribute("selectname", selectname);
request.setAttribute("selectcate", selectcate);
request.setAttribute("Page", pages);
} catch (Exception e) {


}

}else
{

int mytotal;
try {
int totalpage = service.getCount();
if (totalpage % pageSize == 0) {
mytotal = totalpage / pageSize;
} else {
mytotal = totalpage / pageSize + 1;
}
pages.setTotalPages(mytotal);
List<Book> list = service.selectbook((pages.getPageIndex() - 1)
* pages.getPageSize(), pages.getPageSize());
pages.setBooklist(list);
request.setAttribute("Page", pages);


} catch (Exception e) {


}
}

if (action != null) {
// 删除book
if (action.equals("deletebook")) {
String id = request.getParameter("bookid");
try {
int deletebook = service.deletebook(Integer.parseInt(id));
if (deletebook > 0) {
System.out.println("删除成功!");
response.sendRedirect("/BookManager/BookServlet");
} else {
System.out.println("删除失败！");
}
} catch (NumberFormatException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
} else if (action.equals("uploadbook")) {
String bookid = request.getParameter("bookid");
try {
List<BookCategory> catelist = service.selectcategory();
Book book = service.uploadbook(Integer.parseInt(bookid));
request.setAttribute("Book", book);
request.setAttribute("catelist", catelist);
request.getRequestDispatcher("/jsp/bookupdate.jsp")
.forward(request, response);
} catch (NumberFormatException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
// 修改图书
} else if (action.equals("updatebook")) {


String id = request.getParameter("id");
int bookid = Integer.parseInt(id);
Book book = new Book();
PrintWriter writer = response.getWriter();
String filedname = "";
boolean flag = ServletFileUpload.isMultipartContent(request);
if (flag) {
DiskFileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
try {
List<FileItem> item = upload.parseRequest(request);
Iterator<FileItem> items = item.iterator();
while (items.hasNext()) {
FileItem fileitem = (FileItem) items.next();
if (fileitem.isFormField()) {
filedname = fileitem.getFieldName();
if (filedname.equals("bookName")) {
book.setBookname(fileitem
.getString("UTF-8"));
} else if (filedname.equals("bookauthor")) {
book.setBookauthor(fileitem
.getString("UTF-8"));
} else if (filedname.equals("bookcategoryid")) {
book.setBookcategory(Integer
.parseInt(fileitem
.getString("UTF-8")));
} else if (filedname.equals("bookPrice")) {
book.setBookprice(Float.parseFloat(fileitem
.getString("UTF-8")));
} else if (filedname.equals("bookdatetime")) {
String time = fileitem.getString("UTF-8");


SimpleDateFormat simpleDateFormat = new SimpleDateFormat(
"yyyy-MM-dd");
Date date;
try {
date = simpleDateFormat.parse(time);
book.setBookdatatime(date);
} catch (ParseException e) {
e.printStackTrace();
}


} else if (filedname.equals("bookabout")) {
book.setBookabout(fileitem
.getString("UTF-8"));
}
} else {
String tomactPath = this.getServletContext()
.getRealPath("/image/");
String fileName1 = fileitem.getName();
if (fileName1 == "") {
Book books = service.uploadbook(bookid);
book.setBookpicture(books.getBookpicture());
} else {
book.setBookpicture(fileName1);
}


if (fileName1 != null && !fileName1.equals("")) {
File fullFile = new File(fileitem.getName());
File saveFile = new File(tomactPath,
fullFile.getName());
try {
fileitem.write(saveFile);
} catch (Exception e) {
e.printStackTrace();
}
tomactPath = fullFile.getName();
System.out.println("上传成功");
}
}
}
} catch (FileUploadException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
try {
int addbook = service.bookupdate(book, bookid);
if (addbook > 0) {
response.sendRedirect("/BookManager/BookServlet");
} else {
response.sendRedirect("BookManager/BookServlet?action=uploadbook");
}
} catch (Exception e) {
e.printStackTrace();
}
} else if (action.equals("selectbookcatefory")) {


try {
List<BookCategory> catelist = service.selectcategory();
request.setAttribute("catelist", catelist);
request.getRequestDispatcher("/jsp/bookadd.jsp").forward(
request, response);
} catch (Exception e) {
e.printStackTrace();
}


} else if (action.equals("insertbook")) {
Book book = new Book();
PrintWriter writer = response.getWriter();
String filedname = "";
boolean flag = ServletFileUpload.isMultipartContent(request);
if (flag) {
DiskFileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
try {
List<FileItem> item = upload.parseRequest(request);
Iterator<FileItem> items = item.iterator();
while (items.hasNext()) {
FileItem fileitem = (FileItem) items.next();
if (fileitem.isFormField()) {
filedname = fileitem.getFieldName();
if (filedname.equals("bookName")) {
book.setBookname(fileitem
.getString("UTF-8"));
} else if (filedname.equals("bookauthor")) {
book.setBookauthor(fileitem
.getString("UTF-8"));
} else if (filedname.equals("bookcategoryid")) {
book.setBookcategory(Integer
.parseInt(fileitem
.getString("UTF-8")));
} else if (filedname.equals("bookPrice")) {
book.setBookprice(Float.parseFloat(fileitem
.getString("UTF-8")));
} else if (filedname.equals("bookdatetime")) {
String time = fileitem.getString("UTF-8");


SimpleDateFormat simpleDateFormat = new SimpleDateFormat(
"yyyy-MM-dd");
Date date;
try {
date = simpleDateFormat.parse(time);
book.setBookdatatime(date);
} catch (ParseException e) {
e.printStackTrace();
}


} else if (filedname.equals("bookabout")) {
book.setBookabout(fileitem
.getString("UTF-8"));
}
} else {
String tomactPath = this.getServletContext()
.getRealPath("/image/");
String fileName1 = fileitem.getName();
System.out.println(fileName1);
book.setBookpicture(fileName1);
if (fileName1 != null && !fileName1.equals("")) {
File fullFile = new File(fileitem.getName());
File saveFile = new File(tomactPath,
fullFile.getName());
try {
fileitem.write(saveFile);
} catch (Exception e) {
e.printStackTrace();
}
tomactPath = fullFile.getName();
System.out.println("上传成功");
}
}
}
} catch (FileUploadException e) {
e.printStackTrace();
}
}
try {
int addbook = service.addbook(book);
if (addbook > 0) {
response.sendRedirect("/BookManager/BookServlet");
} else {
response.sendRedirect("BookManager/BookServlet?action=selectbookcatefory");
}
} catch (Exception e) {
e.printStackTrace();
}
}else if(action.equals("filedown"))
{
//文件下载的根路径
String  path=getServletContext().getRealPath("/")+"image/";
//取到要下载的文件名称
String filename=request.getParameter("filename");
//读取文件
File  file=new File(path+filename);
//判断file是否为null
if(file!=null){
//设置相应的类型
//setContentType  使客户端浏览器调用不同的模块处理相应的数据
//文件下载所用的类型  application/x-msdownload或application/octet-stream
response.setContentType("application/x-msdownload");
//设置头信息  以复健的形式打开我们的下载文件  下载的时候文件名=filename
response.setHeader("Content-Disposition","attachment;filename=\""+filename+"\"");
//读取我们需要下载的文件
//获取文件输入流
InputStream   inputStream=new FileInputStream(file);
//获取文件返回的输出流
ServletOutputStream  sops=response.getOutputStream();
//循环将输入流信息写入到输出流中
//定义一个变量Byte[]  每次读取1024个字节
byte b[] =new byte[1024];
int n;
while((n=inputStream.read(b))!=-1){//如果不等于-1  循环读取
//写入到输出流中
sops.write(b, 0, n);
}
//关闭流  释放资源
sops.close();
inputStream.close();
}
}
} else {
request.getRequestDispatcher("/jsp/booklist.jsp").forward(request,
response);
}


}
}