struts--crud值

原创于 2019-08-25 15:24:32 发布 · 236 阅读

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本文详细介绍使用Struts框架实现增删改查(CRUD)功能的全过程，涵盖pom依赖导入、web.xml配置、DAO层数据访问、Action层业务处理、Struts配置文件设置及JSP页面展示等关键步骤。

Stryts–crud值（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、定义baseAction，存放结果码常量，请求、响应、上下文、公用的传值

commons-fileupload commons-fileupload 1.3.1

	<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>

chain：Action链式处理的结果类型，也就是将结果转发到这个action中。
redirect：实际上dispatcher和redirect的区别就是在于转发和重定向的区别。
redirectAction：用于直接redirectaction。

2、Struts标签的使用
s:iterator
S:action
S:url
S:form
s:textfield
S:select
S:radio
S:param
s:textarea

1、不直接跳页面，跳子控制器，因为路径问题和*。action配置
	2、修改页面弹栈的问题，load出的结果作为跟，属性可以直接取值
	3、页面样式问题	theme

	<table border="1" width="100%">
		<tr>
			<td>序号</td>
			<td>学号</td>
			<td>姓名</td>
			<td>拼音</td>
			<td>性别</td>
			<td>标记</td>
			<td>班级</td>
			<td>操作</td>
		</tr>
		<s:iterator var="s" value="result">
		<tr>
			<td>序号</td>
			<td><s:property value="#s.sid"/></td>
			<td><s:property value="#s.sname"/></td>
			<td><s:property value="#s.spin"/></td>
			<td><s:property value="#s.sex"/></td>
			<td><s:property value="#s.mark"/></td>
			<td><s:property value="#s.cname"/></td>
			<td>
				
			</td>
		</tr>
		</s:iterator>
	</table>

配置web.xml

<filter>
  <filter-name>encodingFiter</filter-name>
  <filter-class>com.lrc.c.util.EncodingFiter</filter-class>
  </filter>
  <filter-mapping>
  <filter-name>encodingFiter</filter-name>
  <url-pattern>/*</url-pattern>
  </filter-mapping>

l.tld

<?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>lrc 1.1 core library</description>
	<display-name>lrc</display-name>
	<tlib-version>1.1</tlib-version>
	<short-name>c</short-name>
	<uri>/lrc</uri>

	<tag>
		<!-- 标签库中的标签名 -->
		<name>page</name>
		<!-- 标签对应的后台助手类 -->
		<tag-class>com.page.lrc.tag.PageTag</tag-class>
		<!-- 标签类别 -->
		<body-content>JSP</body-content>
		<attribute>
			<!-- 自定义标签携带的属性 -->
			<name>pageBean</name>
			<!-- 属性值是否必填 -->
			<required>true</required>
			<!-- 是否支持表达式（EL/ognl） -->
			<rtexprvalue>true</rtexprvalue>
		</attribute>
	</tag>

	

</taglib>

Clazz

package com.lrc.c.entity;

import java.lang.reflect.Field;

public class Clazz {
	private int cid;
	private String cname;
	private String cteacher;
	private String pic="无";
	public int getCid() {
		return cid;
	}
	public void setCid(int cid) {
		this.cid = cid;
	}
	public String getCname() {
		return cname;
	}
	public void setCname(String cname) {
		this.cname = cname;
	}
	public String getCteacher() {
		return cteacher;
	}
	public void setCteacher(String cteacher) {
		this.cteacher = cteacher;
	}
	public String getPic() {
		return pic;
	}
	public void setPic(String pic) {
		this.pic = pic;
	}
	@Override
	public String toString() {
		return "Clazz [cid=" + cid + ", cname=" + cname + ", cteacher=" + cteacher + ", pic=" + pic + "]";
	}
	public Clazz(int cid, String cname, String cteacher, String pic) {
		super();
		this.cid = cid;
		this.cname = cname;
		this.cteacher = cteacher;
		this.pic = pic;
	}
	public Clazz() {
		super();
	}
	public <T> T newInstance() {
		// TODO Auto-generated method stub
		return null;
	}
	public Field[] getDeclaredFields() {
		// TODO Auto-generated method stub
		return null;
	}
	
	
	
	
}

BaseAction

package com.lrc.c.util;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.ServletResponseAware;

/**
 * 每一个开发的子控制器要用的属性都定义在通用的action中。
 * @author Administrator
 *
 */
public class BaseAction implements ServletRequestAware, ServletResponseAware{
	/**
	 * 为了传值使用
	 */
	protected HttpServletResponse response;
	protected HttpServletRequest request;
	protected HttpSession session;
	protected ServletContext application;
	
	/**
	 * 为了配置跳转页面所用
	 */
	protected final static String SUCCESS = "success";
	protected final static String FAIL = "fail";
	protected final static String LIST = "list";
	protected final static String ADD = "add";
	protected final static String EDIT = "edit";
	protected final static String DETAIL = "detail";
	
	/**
	 * 具体传值字段	后端向jsp页面传值所用字段
	 */
	protected Object result;
	protected Object msg;
	protected int code;

	public Object getResult() {
		return result;
	}

	public Object getMsg() {
		return msg;
	}

	public int getCode() {
		return code;
	}

	@Override
	public void setServletResponse(HttpServletResponse arg0) {
		this.response = arg0;
		
	}

	@Override
	public void setServletRequest(HttpServletRequest arg0) {
		this.request = arg0;
		this.session = arg0.getSession();
		this.application = arg0.getServletContext();
	}
	

}

ClzDao

package com.lrc.c.dao;

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

import com.lrc.c.entity.Clazz;
import com.lrc.c.util.BaseDao;
import com.lrc.c.util.PageBean;
import com.lrc.c.util.StringUtils;

/**
 * 操作数据库
 * @author Administrator
 *
 */
public class ClzDao extends BaseDao<Clazz> {
	/**
	 * 班级列表查询（带分页）
	 * @param clz
	 * @param pageBean
	 * @return
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 * @throws SQLException
	 */
	public List<Clazz> list(Clazz clz, PageBean pageBean) throws Exception{
		String sql = "select * from t_struts_class where true ";
		String cname = clz.getCname();
		int cid = clz.getCid();
		if(StringUtils.isNotBlank(cname)) {
			sql += " and cname like '%"+cname+"%'";
		}
		if(cid != 0) {
			sql += " and cid = "+cid;
		}
		return super.execute(sql, Clazz.class, pageBean);
	}
	
	/**
	 * 班级信息的增加
	 * @param clz
	 * @return
	 * @throws IllegalArgumentException
	 * @throws IllegalAccessException
	 * @throws SQLException
	 */
	public int add(Clazz clz) throws Exception {
		String sql = "insert into t_struts_class values(?,?,?,?)";
		return super.executeUpdate(sql, new String[] {"cid","cname","cteacher","pic"}, clz);
	}
	
	/**
	 * 班级信息的删除
	 * @param clz
	 * @return
	 * @throws IllegalArgumentException
	 * @throws IllegalAccessException
	 * @throws SQLException
	 */
	public int del(Clazz clz) throws Exception {
		String sql = "delete from t_struts_class where cid = ?";
		return super.executeUpdate(sql, new String[] {"cid"}, clz);
	}
	
	/**
	 * 班级信息的修改
	 * @param clz
	 * @return
	 * @throws IllegalArgumentException
	 * @throws IllegalAccessException
	 * @throws SQLException
	 */
	public int edit(Clazz clz) throws Exception {
		String sql = "update t_struts_class set cname=?,cteacher=?,pic=? where cid = ?";
		return super.executeUpdate(sql, new String[] {"cname","cteacher","pic","cid"}, clz);
	}
}

ClazzAction

package com.lrc.c.web;

import java.sql.SQLException;

import com.opensymphony.xwork2.ModelDriven;
import com.lrc.c.dao.ClzDao;
import com.lrc.c.entity.Clazz;
import com.lrc.c.util.BaseAction;
import com.lrc.c.util.PageBean;

public class ClazzAction extends BaseAction implements ModelDriven<Clazz>{
	private ClzDao clzDao = new ClzDao();
	private Clazz clz = new Clazz();

	/**
	 * 查询班级列表的方法
	 * @return
	 */
	public String list() {
		PageBean pageBean = new PageBean();
		pageBean.setRequest(request);
		try {
			this.result = clzDao.list(clz, pageBean);
			request.setAttribute("pageBean", pageBean);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return "list";
	}
	
	/**
	 * 跳转编辑页面（新增编辑页面是同一张）
	 * @return
	 */
	public String preSave() {
//		什么时候跳转新增页面？什么时候跳转编辑页面？
//		区别在于跳编辑页面的时候需要传递cid到后台进行查询，并且将查询到的数据进行回显？
		int cid = clz.getCid();
		if(cid != 0) {
			try {
				this.result = clzDao.list(clz, null).get(0);
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
		return "preSave";
	}
	
	/**
	 * 增加班级信息
	 * @return
	 */
	public String add() {
		try {
			this.code = this.clzDao.add(clz);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return "toList";
	}
	
	/**
	 * 修改班级信息
	 * @return
	 */
	public String edit() {
		try {
			this.code = this.clzDao.edit(clz);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return "toList";
	}
	
	/**
	 * 删除班级信息
	 * @return
	 */
	public String del() {
		try {
			this.code = this.clzDao.del(clz);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return "toList";
	}

	@Override
	public Clazz getModel() {
		return clz;
	}
}

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="/user_*" class="com.lrc.a.UserAction" method="{1}">
	<result name="rs">/text.jsp</result>
	</action>
	<action name="demo_*" class="com.lrc.a.DemoAction" method="{1}">
	<result name="rs">/text2.jsp</result>
	</action>
	<action name="tomcat_*" class="com.lrc.a.TomcatAction" method="{1}">
	<result name="rs">/text2.jsp</result>
	</action>
	<action name="ognl_*" class="com.lrc.b.Demo7" method="{1}">
	<result name="rs"></result>
	</action>
	<action name="lrc_*" class="com.lrc.c.web.ClazzAction" method="{1}">
	<result name="list">/claList.jsp</result>
	<result name="preSave">/clzEdit.jsp</result>
	<result name="toList" type="redirectAction">/clz_list</result>
	</action>
	</package>
</struts>

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>班级的编辑页面</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" value="${result.cid }" name="cid"><br>
	cname:<input type="text" value="${result.cname }" name="cname"><br>
	cteacher:<input type="text" value="${result.cteacher }" name="cteacher"><br>
	<input type="hidden" name="pic" value="${result.pic}"> 
	<input type="submit" value="ok">
</form>
</body>
</html>

claList.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="/lrc" 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>书籍主页</title>
</head>
<body>

	<h2>小说目录</h2>
	<br>

	<form action="${pageContext.request.contextPath}/sy/clz_list.action"
		method="post">
<!-- 		<input type='hidden' name='rows' value="20"> -->
<!-- <input type='hidden' name='pagination' value="false"> -->
		书名：<input type="text" name="bname"> 
		<input type="submit"
			value="确定">
	</form>
	<a href="${pageContext.request.contextPath}/sy/clz_preSave.action">新增</a>
	<table border="1" width="100%">
		<tr>
			<td>编号</td>
			<td>班级名称</td>
			<td>教员</td>
				<td>图片</td>
			<td>操作</td>
		</tr>
		<c:forEach items="${result }" var="c">
			<tr>
				<td>${c.cid }</td>
				<td>${c.cname }</td>
				<td>${c.cteacher }</td>
				<td>${c.pic }</td>
				<td>
				<a href="${pageContext.request.contextPath}/sy/clz_preSave.action?cid=${c.cid }">修改</a>&nbsp;&nbsp;
				<a href="${pageContext.request.contextPath}/sy/clz_del.action?cid=${c.cid }">删除</a>
				</td>
			</tr>
		</c:forEach>
	</table>
	
	<z:page pageBean="${pageBean }"></z:page>

</body>
</html>

特别注意
在这里插入图片描述

chain：Action链式处理的结果类型，也就是将结果转发到这个action中。
redirect：实际上dispatcher和redirect的区别就是在于转发和重定向的区别。
redirectAction：是用于直接redirectaction。

不能直接进入jsp界面，需要进入中央控制器
在这里插入图片描述

在这里插入图片描述