servlet之数据库的增，删，改，查

时间：2022-12-11 20:51:20

查询：

servlet之数据库的增，删，改，查

修改：

servlet之数据库的增，删，改，查servlet之数据库的增，删，改，查servlet之数据库的增，删，改，查

删除：

servlet之数据库的增，删，改，查

添加：

servlet之数据库的增，删，改，查servlet之数据库的增，删，改，查

servlet之数据库的增，删，改，查

代码：

frame.jsp（显示左右界面）

<frameset cols="40%,70%">
<frame src="framemenu.jsp" name="menu">
<frame src="framemain.jsp" name="main">
</frameset>
<body>
</body>
framemenu.jsp 

<body>
<a href="../servlet/FindPage" target="main">用户管理</a><br>
<a href="../servlet/servletInsert.jsp" target="main">添加用户</a><br>
<a href="../successful.jsp" target="main">新闻管理</a>    
</body>
FindPage.java(构造分页) 

public class FindPage extends HttpServlet {
private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public FindPage() {
        super();
        // TODO Auto-generated constructor stub
    }

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//response.getWriter().append("Served at: ").append(request.getContextPath());
int pages;//定义总页数
       int currpage=1;//定义当前页码
       if(request.getParameter("page")!=null){
            currpage=Integer.parseInt(request.getParameter("page"));
         }
       Find fd=new Find();
       int count=fd.SelectCount();
       if(count%User.PAGESIZE==0){
                 pages=count/User.PAGESIZE;
          }else{
                pages=count/User.PAGESIZE+1;
          }
         StringBuffer sb=new StringBuffer();
       for(int i=1;i<=pages;i++){
             if(i==currpage){
               sb.append("["+i+"]");
         }else{
                sb.append("<a href='../servlet/servletPage.jsp?page="+i+"'>"+i+"</a>"); //构建分页条
          }
                 sb.append("  ");
           }
            request.setAttribute("bar", sb.toString());
            request.getRequestDispatcher("servletPage.jsp").forward(request,response);
}
}
servletPage.jsp 

<body>
<table align="center" width="800" border="1">
<tr>
   <td align="center" colspan="5">
    <h2>所有用户信息</h2>
   </td>
</tr>
<tr align="center">
     <td><b>用户名</b></td>
     <td><b>密码</b></td>
     <td><b>用户类型</b></td>
     <td colspan="2"><b>数据操作</b></td>
</tr>
    <%
      int currpage=1;//定义当前页码
      if(request.getParameter("page")!=null){
         currpage=Integer.parseInt(request.getParameter("page"));
      }
      Find find=new Find();
      List<User> listall=new ArrayList<User>();
      listall=find.Selectcontent(currpage);
      Iterator<User> it=listall.iterator();
      while(it.hasNext()){
      User usera=it.next();
     %>
<tr align="center">
  <td><%=usera.getUsername()%></td>
  <td><%=usera.getPassword()%></td>
  <td><%=usera.getType()%></td>
  <td><button><a href="Update?id=<%=usera.getId()%>">修改</a></button></td>
  <td><button><a href="Delete?id=<%=usera.getId()%>">删除</a></button></td>
</tr>
 <%} %>
 <tr>
  <td align="center" colspan="5"> 
    <%=request.getAttribute("bar") %>

  </tr>
</table>
</body>
Delete.java 

public class Delete extends HttpServlet {
private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public Delete() {
        super();
        // TODO Auto-generated constructor stub
    }

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */


/**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
request.setCharacterEncoding("utf-8");
     response.setContentType("text/html;charset=utf-8");
User user=new User();
user.setId(request.getParameter("id"));
UserDao update=new UserDao();
int result=update.Delete(user);
 PrintWriter out =response.getWriter();
if(result!=0){
out.println("删除成功");
response.sendRedirect("FindPage");
}
}

}
Insert.java 

public class Insert extends HttpServlet {
private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public Insert() {
        super();
        // TODO Auto-generated constructor stub
    }

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
/*protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.getWriter().append("Served at: ").append(request.getContextPath());
}
*/
/**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//doGet(request, response);
User user=new User();
     request.setCharacterEncoding("utf-8");
     response.setContentType("text/html;charset=utf-8");
     user.setUsername(request.getParameter("username"));
     user.setPassword(request.getParameter("password"));
     user.setType(request.getParameter("type"));
UserDao add=new UserDao();
int result=add.Insert(user);
if(result!=0){
 PrintWriter out =response.getWriter();
 out.println("添加成功！");
}
}

}
Update.java 

public class Update extends HttpServlet {
private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public Update() {
        super();
        // TODO Auto-generated constructor stub
    }

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */


/**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//doGet(request, response);
request.setCharacterEncoding("utf-8");
     response.setContentType("text/html;charset=utf-8");
User user=new User();
user.setId(request.getParameter("id"));
UserDao update=new UserDao();
ResultSet result=update.Select(user);
try {
if(result.next()){
 PrintWriter out =response.getWriter();
 out.println("<form action='doUpdate?id="+result.getString("id")+"' method='post'>");
 out.println("用户名：<input type='text' value='"+result.getString("username")+"' name='username'>");
 out.println("密 码：<input type='password' value='"+result.getString("password")+"' name='password'>");
 out.println("用户类型：<select name='type'>");
 out.println("<option value='管理员'>管理员</option>");
 out.println("<option value='普通用户'>普通用户</option>");
 out.println("</select>");
 out.println("<input type='submit' value='修改'>");
 out.println("<input type='reset' value='取消'>");
 out.println("</form>");
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}
doUpdate.java 

public class doUpdate extends HttpServlet {
private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public doUpdate() {
        super();
        // TODO Auto-generated constructor stub
    }

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//response.getWriter().append("Served at: ").append(request.getContextPath());
 request.setCharacterEncoding("utf-8");
     response.setContentType("text/html;charset=utf-8");
  UserDao user=new UserDao();//实例化
   User  usera=new User();
   User use=new User();
   PrintWriter out =response.getWriter();
   usera.setId(request.getParameter("id"));
   usera.setUsername(request.getParameter("username"));
   usera.setPassword(request.getParameter("password"));
   usera.setType(request.getParameter("type"));
   use.setId(usera.getId());
   use.setUsername(usera.getUsername());
   use.setPassword(usera.getPassword());
   use.setType(usera.getType());
   int rstu=user.Update(use);
   response.sendRedirect("FindPage");

}
}
web.xml 

<servlet>
    <servlet-name>Login</servlet-name>
    <servlet-class>nuc.test.servlet.Login</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>FindPage</servlet-name>
    <servlet-class>nuc.test.servlet.FindPage</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>Insert</servlet-name>
    <servlet-class>nuc.test.servlet.Insert</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>Update</servlet-name>
    <servlet-class>nuc.test.servlet.Update</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>Delete</servlet-name>
    <servlet-class>nuc.test.servlet.Delete</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>FindAll</servlet-name>
    <servlet-class>nuc.test.servlet.FindAll</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>doUpdate</servlet-name>
    <servlet-class>nuc.test.servlet.doUpdate</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>Login</servlet-name>
    <url-pattern>/servlet/Login</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Update</servlet-name>
    <url-pattern>/servlet/Update</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Delete</servlet-name>
    <url-pattern>/servlet/Delete</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>FindAll</servlet-name>
    <url-pattern>/servlet/FindAll</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>doUpdate</servlet-name>
    <url-pattern>/servlet/doUpdate</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Insert</servlet-name>
    <url-pattern>/servlet/Insert</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>FindPage</servlet-name>
    <url-pattern>/servlet/FindPage</url-pattern>
  </servlet-mapping>










标签：

相关文章