• Struts2的CRUD


    利用struts2完成增删改查

      1、导入相关的pom依赖(struts、自定义标签库的依赖)

    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
      <modelVersion>4.0.0</modelVersion>
      <groupId>com.lww</groupId>
      <artifactId>T224_struts</artifactId>
      <packaging>war</packaging>
      <version>0.0.1-SNAPSHOT</version>
      <name>T224_struts Maven Webapp</name>
      <url>http://maven.apache.org</url>
      <dependencies>
         <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.12</version>
          <scope>test</scope>
        </dependency>
        
        <dependency>
                <groupId>javax.servlet</groupId>
                <artifactId>javax.servlet-api</artifactId>
                <version>4.0.1</version>
                <scope>provided</scope>
        </dependency>
        
         <dependency>
                <groupId>org.apache.struts</groupId>
                <artifactId>struts2-core</artifactId>
                <version>2.5.13</version>
         </dependency>
         
         <!-- 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>
            
            <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
                <version>5.1.40</version>
        </dependency>
    
      </dependencies>
      <build>
        <finalName>T224_struts</finalName>
        <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>3.7.0</version>
                    <configuration>
                        <source>1.8</source>
                        <target>1.8</target>
                        <encoding>UTF-8</encoding>
                    </configuration>
                </plugin>
        </plugins>
      </build>
    </project>

      2、分页的tag类导入、z.tld、完成web.xml的配置

    PageTag 通用分页

    package com.liuwenwu.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.liuwenwu.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) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return super.doStartTag();
        }
        private String toHTML() {
            StringBuffer sb = new StringBuffer();
            /*
             * 拼接向后台提交数据的form表单
             *     注意:拼接的form表单中的page参数是变化的,所以不需要保留上一次请求的值
             */
            sb.append("<form id='pageBeanForm' action='"+pageBean.getUrl()+"' method='post'>");
            sb.append("<input type='hidden' name='page'>");
            Map<String, String[]> parameterMap = pageBean.getParameterMap();
            if(parameterMap != null && parameterMap.size() > 0) {
                Set<Entry<String, String[]>> entrySet = parameterMap.entrySet();
                for (Entry<String, String[]> entry : entrySet) {
                    if(!"page".equals(entry.getKey())) {
                        String[] values = entry.getValue();
                        for (String val : values) {
                            sb.append("<input type='hidden' name='"+entry.getKey()+"' value='"+val+"'>");
                        }
                    }
                }
            }
            sb.append("</form>");
            
            /*
             * 展示的分页条
             */
            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 href='javascript:gotoPage(1)'>首页</a>&nbsp;&nbsp;<a");
            sb.append(" href='javascript:gotoPage("+pageBean.previousPage()+")'>上一页</a>&nbsp;&nbsp;<a");
            sb.append(" href='javascript:gotoPage("+pageBean.nextPage()+")'>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;  50px;'>&nbsp;&nbsp;<a");
            sb.append(" href='javascript:skipPage()'>Go</a>");
            sb.append("</div>");
            
            /*
             * 给分页条添加与后台交互的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();
        }
    }

    z.tld自定义标签配置文件

    <?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>zking 1.1 core library</description>
      <display-name>zking core</display-name>
      <tlib-version>1.1</tlib-version>
      <short-name>z</short-name>
      <uri>/zking</uri>
    
     <tag>
         <!-- 标签库中的标签名 -->
        <name>page</name>
        <!-- 标签对应的助手类的全路径名 -->
        <tag-class>com.liuwenwu.crud.tag.PageTag</tag-class>
        <body-content>JSP</body-content>
        <attribute>
                <!-- 属性名 -->
            <name>pageBean</name>
            <!-- 属性值是否是必填 -->
            <required>true</required>
            <!-- 是否支持表达式 -->
            <rtexprvalue>true</rtexprvalue>
        </attribute>
      </tag>
    </taglib>

    wed.xml配置

    <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.liuwenwu.crud.util.EncodingFiter</filter-class>
      </filter>
      <filter-mapping>
          <filter-name>encodingFiter</filter-name>
          <url-pattern>/*</url-pattern>
      </filter-mapping>
      
          <filter>
              <filter-name>struts</filter-name>
              <filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class>
          </filter>
          <filter-mapping>
              <filter-name>struts</filter-name>
              <url-pattern>*.action</url-pattern>
          </filter-mapping>
    </web-app>

    3、编写dao层去访问数据

    package com.liuwenwu.crud.dao;
    import java.sql.SQLException;
    import java.util.List;
    
    import org.apache.commons.lang3.StringUtils;
    
    import com.liuwenwu.crud.entity.Clazz;
    import com.liuwenwu.crud.util.EntityBaseDao;
    import com.liuwenwu.crud.util.PageBean;
    
    
    public class ClazzDao extends EntityBaseDao<Clazz>{
    
        /**
         * 查询分页,查询单条数据公用方法
         * @param clz
         * @param pageBean
         * @return
         * @throws InstantiationException
         * @throws IllegalAccessException
         * @throws SQLException
         */
        public List<Clazz> list(Clazz clz,PageBean pageBean) throws InstantiationException, IllegalAccessException, SQLException{
            String sql="select * from t_struts_class where true ";
            String cname=clz.getCname();
            int cid=clz.getCid();
            if(cid!=0) {
                sql+=" and cid="+cid;
            }
            if(StringUtils.isNoneBlank(cname)) {
                sql+=" and cname like '%"+cname+"%'";
            }
            return super.executeQuery(sql, pageBean, Clazz.class);
            
        }
        
        /**
         * 新增方法
         * @param clz
         * @return
         * @throws NoSuchFieldException
         * @throws SecurityException
         * @throws IllegalArgumentException
         * @throws IllegalAccessException
         * @throws SQLException
         */
        public int add(Clazz clz) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException {
            String sql="insert into t_struts_class values(?,?,?,?)";
            return super.executeUpdate(sql, new String[] {"cid","cname","cteacher","pic"}, clz);
            
        }
        
        /**
         * 修改方法
         * @param clz
         * @return
         * @throws NoSuchFieldException
         * @throws SecurityException
         * @throws IllegalArgumentException
         * @throws IllegalAccessException
         * @throws SQLException
         */
        public int edit(Clazz clz) 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"}, clz);
            
        }
        /**
         * 删除方法
         * @param clz
         * @return
         * @throws NoSuchFieldException
         * @throws SecurityException
         * @throws IllegalArgumentException
         * @throws IllegalAccessException
         * @throws SQLException
         */
        public int del(Clazz clz) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException {
            String sql="delete from t_struts_class where cid=?";
            return super.executeUpdate(sql, new String[] {"cid"}, clz);
            
        }
    }

    4、web层去调用dao层给前台返回数据

    package com.liuwenwu.crud.web;
    
    import java.sql.SQLException;
    import java.util.List;
    
    import com.liuwenwu.crud.dao.ClazzDao;
    import com.liuwenwu.crud.entity.Clazz;
    import com.liuwenwu.crud.util.PageBean;
    import com.opensymphony.xwork2.ModelDriven;
    
    public class ClazzAction extends BaseAction implements ModelDriven<Clazz>{
        
        private ClazzDao clzDao=new ClazzDao();
        private Clazz clz=new Clazz();
        
        public String list() {
            PageBean pageBean=new PageBean();
            pageBean.setRequest(request);
            try {
                List<Clazz> list= this.clzDao.list(clz, pageBean);
    //            this.result=this.clzDao.list(clz, pageBean);
                request.setAttribute("clzList", list);
                request.setAttribute("pageBean", pageBean);
            } catch (Exception e) {
                e.printStackTrace();
            } 
            return "list";
        }
    
        /**
         * 跳转新增修改页面的公用方法
         * @return
         */
        public String preSave() {
            if(clz.getCid()!=0) {
                try {
                    Clazz c = this.clzDao.list(clz, null).get(0);
                    request.setAttribute("clz", c);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
            return "preSave";
        }
        /**
         * 新增
         * @return
         */
        public String add() {
            try {
                result=this.clzDao.add(clz);
            } catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException
                    | SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return "toList";
        }
        /**
         * 修改
         * @return
         */
        public String edit() {
            try {
                this.clzDao.edit(clz);
            } catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException
                    | SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return "toList";
        }
        /**
         * 删除
         * @return
         */
        public String del() {
            try {
                this.clzDao.del(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.liuwenwu.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>

    6、前端jsp展示页面

    <%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
        <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
        <%@taglib prefix="z" uri="/zking" %>
    <!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>
    <h2>班级</h2><br>
        <form action="${pageContext.request.contextPath }/sy/clz_list.action" method="post">
            班级名:<input type="text" name="cname">
                  <input type="submit" value="确定">
        </form>
        <a href="${pageContext.request.contextPath }/sy/clz_preSave.action">新增</a>
        <table border="1" width="100%">
            <tr>
                <td>编号</td>
                <td>班级名</td>
                <td>教员</td>
                <td>图片</td>
                <td>操作</td>
            </tr>    
            <c:forEach items="${clzList }" var="c">
            <tr>
                <td>${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=${c.cid}">删除</a>&nbsp;&nbsp;
                    <a href="${pageContext.request.contextPath }/sy/clz_preUpload.action?cid=${c.cid}">图片上传</a>&nbsp;&nbsp;
                </td>
            </tr>    
            </c:forEach>
        </table>
        <z:page pageBean="${pageBean }"></z:page>
        
    </body>
    </html>

    成果:

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  • 原文地址:https://www.cnblogs.com/liuwenwu9527/p/11108611.html
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