今天分享的是struts2框架中增删改查的用法：
一：利用Struts2框架
1.1在pom.xml中导入相关依赖
<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.ht</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> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> <version>2.2.1-b03</version> <scope>provided</scope> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.44</version> </dependency> <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> </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>
二：导入分页相关的通用pageBean类，z.tld，并且配置web.xml
2.1 导入pageBean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; /** * 分页通用类 * @author Administrator */ 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 <a href='javascript:gotoPage(1)'>首页</a> <a"); sb.append(" href='javascript:gotoPage("+pageBean.previousPage()+")'>上一页</a> <a"); sb.append(" href='javascript:gotoPage("+pageBean.nextPage()+")'>下一页</a> <a"); sb.append(" href='javascript:gotoPage("+pageBean.getMaxPage()+")'>尾页</a> <input type='text'"); sb.append(" id='skipPage'"); sb.append(" style='text-align: center; font-size: 12px; 50px;'> <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(); } }
2.2 z.tld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> <name>page</name> <tag-class>com.crud.tag.PageTag</tag-class> <body-content>JSP</body-content> <attribute> <name>pageBean</name> <required>true</required> <rtexprvalue>true</rtexprvalue> </attribute> </tag> </taglib>
2.3 配置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.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> <!-- 相对于中央控制器，过滤请求 --> <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>
三：在Mysql中设计数据库
3.1 在项目中配置与mysql数据库连接
数据库用户名和密码是不一样的看你们自己怎么设置的
四：编写Dao层去访问数据库
package com.crud.dao; import java.sql.SQLException; import java.util.List; import com.crud.entity.Class; import com.crud.util.BaseDao; import com.crud.util.EntityBaseDao; import com.crud.util.PageBean; import com.crud.util.StringUtils; /** * 班级dao方法类 * @author Administrator */ public class ClassDao extends EntityBaseDao<Class>{ /** * 查询分页方法，查询数据公用方法 * @param c * @param paBean * @return * @throws InstantiationException * @throws IllegalAccessException * @throws SQLException */ public List<Class> list(Class c,PageBean paBean) throws InstantiationException, IllegalAccessException, SQLException{ String sql="select * from struts_class where true "; String classname=c.getClassname(); int cid=c.getCid(); if (cid!=0) { sql +=" and cid = "+cid; } if (StringUtils.isNotBlank(classname)) { sql+=" and classname like '%"+classname+"%'"; } return super.executeQuery(sql,paBean,Class.class); } /** * 新增方法 * @param c * @return * @throws NoSuchFieldException * @throws SecurityException * @throws IllegalArgumentException * @throws IllegalAccessException * @throws SQLException */ public int add(Class c) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException { String sql="insert into struts_class values(?,?,?)"; return super.executeUpdate(sql, new String[] {"classname","cname","upload"},c); } /** * 删除方法 * @param c * @return * @throws NoSuchFieldException * @throws SecurityException * @throws IllegalArgumentException * @throws IllegalAccessException * @throws SQLException */ public int del(Class c) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException { String sql="delete from struts_class where cid=?"; return super.executeUpdate(sql, new String[] {"cid"},c); } /** * 修改方法 * @param c * @return * @throws NoSuchFieldException * @throws SecurityException * @throws IllegalArgumentException * @throws IllegalAccessException * @throws SQLException */ public int edit(Class c) throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException, SQLException { String sql="update struts_class set classname=?,cname=?,upload=? where cid=?"; return super.executeUpdate(sql, new String[] {"cid","classname","cname","upload"},c); } }
五：编写web层去调用dao层的方法返回数据给前台
ClassAction 类
package com.crud.web; import java.sql.SQLException; import java.util.List; import com.crud.dao.ClassDao; import com.crud.entity.Class; import com.crud.util.PageBean; import com.opensymphony.xwork2.ActionSupport; import com.opensymphony.xwork2.ModelDriven; /** * 班级web层 * @author Administrator */ public class ClassAction extends BaseAction implements ModelDriven<Class>{ private ClassDao cldao=new ClassDao(); private Class cls=new Class(); public String list() { PageBean pageBean=new PageBean(); pageBean.setRequest(request); try { List<Class> list = this.cldao.list(cls, pageBean); request.setAttribute("mylist", list); request.setAttribute("pageBean", pageBean); } catch (InstantiationException | IllegalAccessException | SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return "list"; } /** * 跳转新增修改页面的公用方法 * @return * @throws SQLException * @throws IllegalAccessException * @throws InstantiationException */ public String preSave() throws InstantiationException, IllegalAccessException, SQLException { if (cls.getCid()!=0) { Class cl = this.cldao.list(cls, null).get(0); request.setAttribute("cls",cl); } return "preSave"; } /** * 新增 * @return */ public String add() { try { result = this.cldao.add(cls); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } return "toList"; } /** * 删除 * @return */ public String del() { try { this.cldao.del(cls); } catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException | SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return "toList"; } /** * 修改 * @return */ public String edit() { try { this.cldao.edit(cls); } catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException | SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return "toList"; } @Override public Class getModel() { // TODO Auto-generated method stub return null; } }
这里实现了一个BaseAction 类
package com.crud.web; 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(); } }
六：配置struts_sy.xml文件
<!-- *代表你要调用的方法 -->
<action name="/cls_*" class="com.crud.web.ClassAction" method="{1}">
<result name="list">/clsList.jsp</result>
<result name="preSave">/clsupdate.jsp</result>
<result name="toList" type="redirectAction">/cls_list</result>
</action>
七：连接前端显示数据并且调用实现效果
ClsList.jsp(显示数据并且调用Crud)
<%@ 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="${pageContext.request.contextPath }/sy/cls_list.action" method="post"> 班级名：<input type="text" name="classname"> <input type="submit" value="确定"> </form> <a href="${pageContext.request.contextPath }/sy/cls_preSave.action">新增</a> <table border="1" width="100%"> <tr> <td>编号</td> <td>班级名</td> <td>学生名</td> <td>图片</td> <td>操作</td> </tr> <c:forEach items="${mylist }" var="c"> <tr> <td>${c.cid }</td> <td>${c.classname }</td> <td>${c.cname}</td> <td>${c.upload }</td> <td> <a href="${pageContext.request.contextPath }/sy/cls_preSave.action?cid=${c.cid}">修改</a> <a href="${pageContext.request.contextPath }/sy/cls_del.action?cid=${c.cid}">删除</a> <a href="${pageContext.request.contextPath }/sy/cls_upload.action?cid=${c.cid}">图片上传</a> </td> </tr> </c:forEach> </table> <z:page pageBean="${pageBean }"></z:page> </body> </html>
Clsupdate.jsp(新增与修改公用界面)
<%@ 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="${pageContext.request.contextPath}${cls.classname ==null ? '/sy/cls_add.action' :'/sy/cls_edit.action'}" method="post"> cid:<input type="text" name="cid" value="${cls.cid}"><br> classname:<input type="text" name="classname" value="${cls.classname }"><br> cname:<input type="text" name="cname" value="${cls.cname }"><br> upload:<input type="text" name="upload" value="${cls.upload }"><br> <input type="submit" value="提交"> </form> </body> </html>
最后：展示效果
谢谢观看！今天的分享到此结束！