struta的增删改查

最新推荐文章于 2021-10-28 01:35:30 发布

原创最新推荐文章于 2021-10-28 01:35:30 发布 · 140 阅读

CC 4.0 BY-SA版权

今天我们要学习的是利用struts完成增删改查
思路：
1、导入相关的pom依赖（struts、自定义标签库的依赖）
2、分页的tag类导入、z.tld、完成web.xml的配置
3、dao层去访问数据
4、web层去调用dao层给前台返回数据
5、在struts_sy.xml进行配置
6、写jsp

1、导入相关的pom依赖（struts、自定义标签库的依赖）

我们在上节课的pom基础上加上这一串依赖！

<!-- 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类

package com.crud.tag;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import com.crud.util.PageBean;

public class pageTag extends BodyTagSupport {
	private static final long serialVersionUID = 1L;
	private PageBean pageBean;
	public PageBean getPageBean() {
		return pageBean;
	}
	public void setPageBean(PageBean pageBean) {
		this.pageBean = pageBean;
	}
	@Override
	public int doStartTag() throws JspException {
		JspWriter out = pageContext.getOut();
		try {
			out.print(toHTML());
		} catch (IOException e) {
			e.printStackTrace();
		}
		return super.doStartTag();
	}
	public String toHTML() {
		StringBuilder sb=new StringBuilder();
		sb.append("<form id='pageBeanForm' action='"+pageBean.getUrl()+"' method='post'>");
		sb.append("<input type='hidden' name='page'>");
		Map<String, String[]> paMap = pageBean.getPaMap();
		if(paMap != null && paMap.size()>0) {
			Set<Entry<String, String[]>> entrySet = paMap.entrySet();
			for (Entry<String, String[]> entry : entrySet) {
//				上一次请求可能携带页码name=page的参数,但是该参数在前面已经赋值
//				为什么要单独赋值，因为上一次请求是第一页数据，下一次可能是第二页，意味着前后请求page对应的值是不一样的，需要单独赋值
				if(!"page".equals(entry.getKey())) {
//					考虑复选框
					for(String val:entry.getValue()) {
						sb.append("<input type='hidden' name='"+entry.getKey()+"' value='"+val+"'>");
					}
				}
			}
		}
		sb.append("</form>");



//		拼接分页条
		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;<a");
		sb.append(" href='javascript:gotoPage(1)'>首页</a>&nbsp;&nbsp;<a");
		sb.append(" href='javascript:gotoPage("+pageBean.getPreviousPage()+")'>上一页</a>&nbsp;&nbsp;<a");
		sb.append(" href='javascript:gotoPage("+pageBean.getNextPage()+")'>下一页</a>&nbsp;&nbsp;<a");
		sb.append(" href='javascript:gotoPage("+pageBean.getMaxPage()+")'>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()'>Go</a>");
		sb.append("</div>");
		
//		拼接分页所需要的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();
	}

}

然后z.tld完成分页自定义标签分页的配置
web.xml的配置就是把那个防止乱码的过漉器配置好就行了

<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.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

package com.crud.dao;

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

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

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 {
		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 {
		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 {
		String sql = "update t_struts_class set cname=?,cteacher=?,pic=? where cid=?";
		return super.executeUpdate(sql, new String[] {"cname","cteacher","pic","cid"}, clazz);
	}
}

增删改查都在里面

4、web层去调用dao层给前台返回数据

package com.crud.web;

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

import com.crud.dao.ClazzDao;
import com.crud.util.BaseAction;
import com.crud.util.PageBean;
import com.curd.entity.Clazz;
import com.opensymphony.xwork2.ModelDriven;

public class ClazzAction extends BaseAction implements ModelDriven<Clazz>{
	private Clazz clz=new Clazz();
	private ClazzDao clazzDao=new ClazzDao();
	public String list() {
		PageBean pageBean=new PageBean();
		pageBean.setRequest(request);
		try {
			List<Clazz> list = this.clazzDao.list(clz, pageBean);
			request.setAttribute("clzList", list);
			request.setAttribute("pageBean", pageBean);
		} catch (InstantiationException | IllegalAccessException | SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return "list";
	}
	/**
	 * 跳转编辑页面（新增修改页面）
	 * @return
	 */
	public String preSave() {
		if(clz.getCid() !=0) {
			try {
				this.result= this.clazzDao.list(clz, null).get(0);
			} catch (InstantiationException | IllegalAccessException | SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return "preSave";
		
	}
	
	public String add() {
		try {
			this.clazzDao.add(clz);
		} catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException
				| SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return "toList";
		
	}
	public String del() {
		try {
			this.clazzDao.del(clz);
		} catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException
				| SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return "toList";
		
	}
	public String edit() {
		try {
			this.clazzDao.edit(clz);
		} catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException
				| SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return "toList";
		
	}
	
	
	
	
	
	@Override
	public Clazz getModel() {
		// TODO Auto-generated method stub
		return clz;
	}
	
}

5、在struts_sy.xml进行配置


		<action name="/clz_*" class="com.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>

记住前面一定别打那个/sy/忘记了！

6、写jsp

clzList.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
        <%@ taglib uri="/zking" prefix="z" %>
<!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>班级主界面</title>
</head>
<body>
<h2>小说目录</h2>
	<br>

	<form action="${pageContext.request.contextPath}/sy/clz_list.action" method="post">
		<input type="hidden" name="pagination" value="true">
		书名：<input type="text" name="bname"> <input type="submit"
			value="确定">
	</form>
	<a href="${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>教员</td>
			<td>班级图片</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=${b.cid}">修改</a>&nbsp;&nbsp;
				<a href="${pageContext.request.contextPath}/sy/clz_del.action?cid=${b.cid}">删除</a>&nbsp;&nbsp;
				<a href="${pageContext.request.contextPath}/sy/clz_del.action?cid=${b.cid}">图片上传</a>&nbsp;&nbsp;
				</td>
			</tr>
		</c:forEach>
	</table>
	
	<!-- 直接调用page标签就好了 -->
	<z:page pageBean="${pageBean}"></z: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="${result.cid }"><br>
	cname：<input type="text" name="cname" value="${result.cname }"><br>
	cteacher：<input type="text" name="cteacher" value="${result.cteacher }"><br>
	pic：<input type="text" name="pic" value="${result.pic }"><br>
	<input type="submit">
</form>
</body>
</html>

运行结果
查询：
在这里插入图片描述
增加：

修改赋值