码迷，mamicode.com
首页 > 其他好文 > 详细

struts的增删改查

时间：2019-07-30 01:05:59      阅读：149      评论：0      收藏：0      [点我收藏+]

标签：ping   Servle   stat   support   name   rest   rect   完成   img   

1、导入相关的pom依赖（struts、自定义标签库的依赖）

<!-- 5.3、jstl、standard -->
<dependency>
<groupId>jstl</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>taglibs</groupId>
<artifactId>standard</artifactId>
<version>1.1.2</version>
</dependency>

<!-- 5.4、tomcat-jsp-api -->
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-jsp-api</artifactId>
<version>8.0.47</version>
</dependency>


2、分页的tag类导入、z.tld、完成web.xml的配置

pageTag.java

package com.huang.crud.tag;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;

import com.huang.crud.util.PageBean;



public class PageTag extends BodyTagSupport {
    
    private static final long serialVersionUID = -8476740758233598045L;
    private PageBean pageBean;
    
    @Override
    public int doStartTag() throws JspException {
        JspWriter out = pageContext.getOut();
        try {
            out.write(toHTML());
        } catch (IOException e) {
            e.printStackTrace();
        }
        return super.doStartTag();
    }

    public String toHTML() {
//    pageBean=new PageBean();
    StringBuffer sb=new StringBuffer();
    //下一次请求提交到后台的表单html代码拼接
    sb.append("<link rel=\"stylesheet\" type=\"text/css\" href=\"css/bootstrap.min.css\"/>");
    sb.append("<script type=\"text/javascript\" src=\"js/jquery-3.3.1.js\"></script>");
    sb.append("<script type=\"text/javascript\" src=\"js/bootstrap.min.js\"></script>");
    sb.append("<form id=‘pageBeanForm‘ action=‘"+pageBean.getUrl()+"‘ method=‘post‘>");
    Map<String, String[]> paramMap = pageBean.getParameterMap();
    if(paramMap!=null&&paramMap.size()>0) {
        for(Entry<String, String[]> entry:paramMap.entrySet()) {
            if(!"page".equals(entry.getKey())) {
                for(String val:entry.getValue()) {
                    sb.append("<input type=‘hidden‘ name=‘"+entry.getKey()+"‘> value=‘"+val+"‘");
                }
            }
        }
    }
    sb.append("<input type=‘hidden‘ name=‘page‘>");
    sb.append("</form>");
    
    
    //分页条html代码拼接
    sb.append("<div style=‘text-align: right; font-size: 12px;‘>");
    sb.append(" 每页"+pageBean.getRows()+"条，共"+pageBean.getTotal()+"条，第"+pageBean.getPage()+"页，共"+pageBean.getMaxPage()+"页&nbsp;&nbsp;");
    sb.append(" <a href=‘javascript:gotoPage(1)‘ class=‘btn btn-default‘>首页</a>&nbsp;&nbsp;<a");
    sb.append(" href=‘javascript:gotoPage("+pageBean.getPreviousPage()+")‘ class=‘btn btn-default‘>上一页</a>&nbsp;&nbsp;<a");
    sb.append(" href=‘javascript:gotoPage("+pageBean.getNextPage()+")‘ class=‘btn btn-default‘>下一页</a>&nbsp;&nbsp;<a");
    sb.append(" href=‘javascript:gotoPage("+pageBean.getMaxPage()+")‘ class=‘btn btn-default‘>尾页</a>&nbsp;&nbsp;<input type=‘text‘");
    sb.append(" id=‘skipPage‘");
    sb.append(" style=‘text-align: center; font-size: 12px; width: 50px;‘>&nbsp;&nbsp;<a");
    sb.append(" href=‘javascript:skipPage()‘ class=‘btn btn-default‘>Go</a>");
    sb.append(" </div>");
    
    
    //分页所需要调用的js代码
    sb.append("<script type=‘text/javascript‘>");
    sb.append("        function gotoPage(page) {");
    sb.append("          document.getElementById(‘pageBeanForm‘).page.value = page;");
    sb.append("          document.getElementById(‘pageBeanForm‘).submit();");
    sb.append("        }");
    sb.append("        function skipPage() {");
    sb.append("          var page = document.getElementById(‘skipPage‘).value;");
    sb.append("          if(!page || isNaN(page) || parseInt(page)<1 || parseInt(page)>"+pageBean.getMaxPage()+"){");
    sb.append("          alert(‘请输入1~N的数字‘);");
    sb.append("          return;");
    sb.append("        }");
    sb.append("        gotoPage(page);");
    sb.append("    }");
    sb.append("</script>");
    
        return sb.toString();
    }

    public PageBean getPageBean() {
        return pageBean;
    }

    public void setPageBean(PageBean pageBean) {
        this.pageBean = pageBean;
    }
}

z.tid

<?xml version="1.0" encoding="UTF-8" ?>

<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
    version="2.0">
  <description>dj 1.1 core library</description>
  <display-name>dj core</display-name>
  <tlib-version>1.1</tlib-version>
  <short-name>d</short-name>
  <uri>/huang</uri>

 <tag>
    <name>page</name>
    <tag-class>com.huang.crud.tag.PageTag</tag-class>
    <body-content>JSP</body-content>
    <attribute>
        <name>pageBean</name>
        <required>true</required>
        <rtexprvalue>true</rtexprvalue>
    </attribute>
  </tag>
  
</taglib>

web.xml

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
  <display-name>Archetype Created Web Application</display-name>
  
   <filter>
      <filter-name>encodingFiter</filter-name>
      <filter-class>com.huang.crud.util.EncodingFiter</filter-class>
  </filter>
  <filter-mapping>
      <filter-name>encodingFiter</filter-name>
      <url-pattern>/*</url-pattern>
  </filter-mapping>
 
  <filter>
  <filter-name>struts2</filter-name>
  
  <filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class>
  
  </filter>
  <filter-mapping>
  <filter-name>struts2</filter-name>
  <url-pattern>*.action</url-pattern>
  </filter-mapping>
</web-app>

 

3、dao层去访问数据

ClazzDao.java

package com.huang.crud.dao;

import java.sql.SQLException;
import java.util.List;

import com.huang.crud.entity.Clazz;
import com.huang.crud.util.BaseDao;
import com.huang.crud.util.PageBean;
import com.huang.crud.util.StringUtils;

public class ClazzDao extends BaseDao<Clazz> {

    public List<Clazz> list(Clazz clazz,PageBean pageBean) throws InstantiationException, IllegalAccessException, SQLException{
        String sql= "select * from t_struts_class where true ";
        String cname= clazz.getCname();
        int cid=clazz.getCid();
         if(cid!=0) {
             sql +=" and cid ="+cid; 
         }
        
        if(StringUtils.isNotBlank(cname)) {
            sql +=" and cname like ‘%"+cname+"%‘";
        }
        
        return super.executeQuery(sql,Clazz.class , pageBean);
        
    }
    
    public int add(Clazz clazz) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException, InstantiationException {
        String sql= "insert into t_struts_class values(?,?,?,?)";
        return super.executeUpdate(sql,new String[] {"cid","cname","cteacher","pic"}, clazz);
    }
    
    
    public int del(Clazz clazz) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException, InstantiationException {
        String sql= "delete from t_struts_class where cid=?";
        return super.executeUpdate(sql,new String[] {"cid"}, clazz);
    }
    
    public int edit(Clazz clazz) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException, InstantiationException {
        String sql= "update  t_struts_class set cname=?,cteacher=?,pic=? where cid=?";
        return super.executeUpdate(sql,new String[] {"cname","cteacher","pic","cid"}, clazz);
    }
}

BaseDao.java

package com.huang.crud.util;

import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import com.huang.crud.entity.Clazz;


public class BaseDao<T> {
    
    
    /**
     * T=Student.class
     * 
     * @param sql     决定查询哪张表的数据
     * @param clz    查询出来的数据封装到哪个实体类中
     * @param pageBean    决定是否分页
     * @return
     * @throws 
     * @throws InstantiationException 
     * @throws SQLException 
     * @throws IllegalAccessException 
     * @throws IllegalArgumentException 
     * @throws InstantiationException 
     */
    public List<T> executeQuery(String sql,Class clz,PageBean pageBean) throws SQLException, IllegalArgumentException, IllegalAccessException, InstantiationException {
        List<T> ls=new ArrayList<>();
        Connection con=DBAccess.getConnection();
        PreparedStatement ps = null;
        ResultSet rs = null;
        
        if(pageBean!=null && pageBean.isPagination()) {
            //该分页了
            String countSql=getCountSql(sql);//获取符合记录的行数的Sql语句
            try {
                ps=con.prepareStatement(countSql);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            try {
                rs=ps.executeQuery();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            if(rs.next()) {
                pageBean.setTotal(rs.getLong(1)+"");//给pageBean的总页数赋值
            }
            
            String pageSql=getPageSql(sql,pageBean);//拼接上符合条件的分页查询sql语句
            ps=con.prepareStatement(pageSql);
            rs=ps.executeQuery();
        }
        else {
             ps = con.prepareStatement(sql);
             rs = ps.executeQuery();
        }
        
        try {
            while (rs.next()) {
                //            ls.add(new Book(rs.getInt("bid"),
                //                    rs.getString("bname"),
                //                    rs.getFloat("price")));
                /**
                 * 1、创建了一个book对象
                 * 2、从ResultSet结果集中获取值放入Book对象属性中
                 *         2.1获取到book的属性对象
                 *         2.2给属性对象赋值
                 * 3、将已经有值的Book对象放进list集合中
                 * 
                 */
                T t = (T) clz.newInstance();
                Field[] fields = clz.getDeclaredFields();
                for (Field field : fields) {
                    field.setAccessible(true);
                    field.set(t, rs.getObject(field.getName()));
                }
                ls.add(t);
            } 
        } finally {
            DBAccess.close(con,ps,rs);
        }
        return ls;
    }

    
    /**
     * 将原生sql拼接出符合条件的某一页的数据查询
     * @param sql
     * @return
     */
    private String getPageSql(String sql,PageBean pageBean) {
        return sql + " limit "+pageBean.getStartIndex()+","+pageBean.getRows();
    }

    /**
     * 用原生sql拼接出查询符合条件的记录数
     * @param sql
     * @return
     */
    private String getCountSql(String sql) {
        return "select count(1) from ("+sql+") t";
    }
    
    
    /**
     * 通用的增删改方法
     * @param sql    增删改的sql语句
     * @param attrs    ？所代表的实体类的属性
     * @param t        实体类的实例
     * @return
     * @throws SQLException
     * @throws NoSuchFieldException
     * @throws SecurityException
     * @throws IllegalArgumentException
     * @throws IllegalAccessException
     * @throws InstantiationException 
     */
    public int executeUpdate(String sql, String[] attrs, T t) throws SQLException, NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, InstantiationException {
        Connection con = DBAccess.getConnection();
        PreparedStatement pst = con.prepareStatement(sql);
        for (int i = 0; i < attrs.length; i++) {
            Field field = t.getClass().getDeclaredField(attrs[i]);
            field.setAccessible(true);
            pst.setObject(i+1, field.get(t));
        }
        return pst.executeUpdate();
    }
}

 

4、在struts_sy.xml进行配置

struts_sy.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"
    "http://struts.apache.org/dtds/struts-2.5.dtd">
<struts>
    <package name="sy" extends="base" namespace="/sy">
      <action name="/clz_*" class="com.huang.crud.web.ClazzAction" method="{1}">
       <result name="list">/clzList.jsp</result>
       <result name="preSave">/clzEdit.jsp</result>
       <result name="toList" type="redirectAction">/clz_list</result>
      </action>
      
    </package>
</struts>

5、写jsp

clzList.jsp

 

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@ taglib uri="/huang" prefix="d" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>主界面</title>
</head>
<body>
<h2>小说目录</h2>
    <br>

    <form action="${pageContext.request.contextPath}/sy/clz_list.action"
        method="post">
        书名：<input type="text" name="bname"> <input type="submit"
            value="确定">
            <input type="hidden" name="rows" value="15">
    </form>
    <a href="${pageContext.request.contextPath}/sy/clz_preSave.action">增加</a>
    <table border="1" width="100%">
        <tr>
            <td>编号</td>
            <td>班级名称</td>
            <td>班级图片</td>
            <td>操作</td>
        </tr>
        <c:forEach items="${clzList }" var="b">
            <tr>
                <td>${b.cid }</td>
                <td>${b.cname }</td>
                <td>${b.cteacher }</td>
                <td>${b.pic }</td>
                <td>
                    <a href="${pageContext.request.contextPath}/sy/clz_preSave.action?cid=${b.cid}">修改</a>&nbsp;
                    <a href="${pageContext.request.contextPath}/sy/clz_del.action?cid=${b.cid}">删除</a>
                    <a href="${pageContext.request.contextPath}/sy/clz_preUpload.action?cid=${b.cid}">文件上传</a>
                </td>
            </tr>
        </c:forEach>
    </table>
    
    <d:page pageBean="${pageBean }"></d:page>
</body>
</html>

 

 

 

clzEdit.jsp

 

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="${pageContext.request.contextPath }${result.cname == null ? ‘/sy/clz_add.action‘ : ‘/sy/clz_edit.action‘}" method="post">
 cid:<input type="text" name="cid" value="${result.cid }"/>
 cname:<input type="text" name="cname" value="${result.cname }"/> 
 cteacher:<input type="text" name="cteacher" value="${result.cteacher }"/>
 
<input type="submit"/>
</form>
</body>
</html>

 

运行结果：

技术图片

 

struts的增删改查

标签：ping   Servle   stat   support   name   rest   rect   完成   img   

原文地址：https://www.cnblogs.com/bf6rc9qu/p/11267323.html
踩
(0)
赞
(0)
   
举报
评论 一句话评论（0）
登录后才能评论！
分享档案
更多>
2021年07月29日 (22)
2021年07月28日 (40)
2021年07月27日 (32)
2021年07月26日 (79)
2021年07月23日 (29)
2021年07月22日 (30)
2021年07月21日 (42)
2021年07月20日 (16)
2021年07月19日 (90)
2021年07月16日 (35)
周排行
mamicode.com排行更多图片
更多
友情链接
兰亭集智   国之画   百度统计   站长统计   阿里云   chrome插件   新版天听网
关于我们 - 联系我们 - 留言反馈
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码！