Mybatis.xml |
xml version="1.0" encoding="UTF-8"?> DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <environments default="default"> <environment id="default"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql:///ssm1"/> <property name="username" value="root"/> <property name="password" value="123"/> dataSource> environment> environments> <mappers> <mapper resource="com/pshdhx/mapper/FlowerMapper.xml"/> mappers> configuration> |
Mapper.xml |
xml version="1.0" encoding="UTF-8"?> DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="a.b"> <select id="selAll" resultType="com.pshdhx.pojo.Flower"> select * from flower select> mapper> |
Test.java |
package com.pshdhx.test;
import java.io.IOException; import java.io.InputStream; import java.util.List;
import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import com.pshdhx.pojo.Flower;
public class Test { public static void main(String[] args) throws IOException{ InputStream is = Resources.getResourceAsStream("mybatis.xml"); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is); SqlSession session = factory.openSession(); List for(Flower flower:list){ System.out.println(flower.toString()); } session.close(); } }
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res.setContentType("text/html;charset=utf-8"); |
记住:是request,是text形式请求 |
Session.selectList() |
Session.selectOne() |
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Session.selectMap() |
有pojo实体类,xml核心配置文件,xml映射文件,service,servlet |
package com.pshdhx.service.impl; import java.io.IOException; import java.io.InputStream; /** * 在数据访问层和控制器中处理异常,在service层中只抛出异常 */ import java.util.List;
import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import com.pshdhx.pojo.People; import com.pshdhx.service.PeopleService;
public class PeopleServiceImpl implements PeopleService {
@Override public List InputStream is = Resources.getResourceAsStream("mybatis.xml"); /** * 前面是工厂,实例化工厂对象时使用的是 构建者模式:意义:简化对象实例化的过程,就是is流的转化的过程,省去了configuration和parse过程,不用new工厂了 * 有适配器设计模式 adapter */ SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is); SqlSession session = factory.openSession(); List session.close(); return list; }
} |
xml version="1.0" encoding="UTF-8"?> DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.pshdhx.mapper.PeopleMapper"> <select id="selAll" resultType="com.pshdhx.pojo.People"> select * from people select> mapper> |
xml version="1.0" encoding="UTF-8"?> DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <environments default="default"> <environment id="default"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql:///ssm1"/> <property name="username" value="root"/> <property name="password" value="123"/> dataSource> environment> environments> <mappers> <mapper resource="com/pshdhx/mapper/PeopleMapper.xml"/> mappers> configuration> |
package com.pshdhx.servlet;
import java.io.IOException; import java.util.List;
import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;
import com.pshdhx.pojo.People; import com.pshdhx.service.PeopleService; import com.pshdhx.service.impl.PeopleServiceImpl;
@WebServlet("/show") public class ShowServlet extends HttpServlet{ private PeopleService peopleService = new PeopleServiceImpl(); @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // TODO Auto-generated method stub List req.setAttribute("list", list); //相对路径 // /表示项目根目录 即是webcontent目录。 req.getRequestDispatcher("index.jsp").forward(req, resp); } } |
log4j.rootCategory=info, CONSOLE ,LOGFILE
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout log4j.appender.CONSOLE.layout.ConversionPattern=%C %p %m %n
log4j.appender.LOGFILE=org.apache.log4j.FileAppender log4j.appender.LOGFILE.File=E:/my.log log4j.appender.LOGFILE.Append=true log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout log4j.appender.LOGFILE.layout.ConversionPattern=%C %m %L %n
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package com.pshdhx.test;
import org.apache.log4j.Logger;
public class Test { public static void main(String[] args) { Logger logger = Logger.getLogger(Test.class); logger.debug("这是调试信息"); logger.info("这是普通信息"); } }
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在mybatis中的全部配置文件中使用log4j |
<configuration> <settings> <setting name="logImpl" value="LOG4J"/> settings> |
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控制参数类型:
如果希望传递多个参数,那么是map
int pageSize = 2; int pageNumber = 1; Map map.put("pageSize", pageSize); map.put("pageStart", pageSize*(pageNumber-1)); List System.out.println(p); session.close(); |
<select id="page" resultType="com.pshdhx.pojo.People" parameterType="map"> select * from people limit #{pageStart} , #{pageSize} 两个参数都是map里边的key ,value值在java类类中被定义了 --> select> |
<typeAliases> <package name="com.pshdhx.pojo"/> typeAliases>
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People peo = new People(); peo.setName("pshdhx"); peo.setAge(23); int index = session.insert("a.b.ins",peo); session.commit(); if(index>0){ System.out.println("success"); }else{ System.out.println("false"); } session.close(); |
Roolback放在catch里边 |
package com.pshdhx.servlet;
import java.io.IOException;
import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;
import com.pshdhx.pojo.PageInfo; import com.pshdhx.service.PeopleService; import com.pshdhx.service.impl.PeopleServiceImpl; @WebServlet("/page") public class ShowPageServlet extends HttpServlet{ private PeopleService peopleService = new PeopleServiceImpl(); @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { String pageSizeStr = req.getParameter("pageSize"); int pageSize=2; if(pageSizeStr !=null &&!pageSizeStr.equals("")){ pageSize = Integer.parseInt(pageSizeStr); } String pageNumberStr =req.getParameter("pageNumber"); int pageNumber=1; if(pageNumberStr!=null&&!pageNumberStr.equals("")){ pageNumber = Integer.parseInt(pageNumberStr); }
PageInfo pi = peopleService.showPage(pageSize, pageNumber); req.setAttribute("PageInfo", pi); req.getRequestDispatcher("index.jsp").forward(req, resp);
} }
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package com.pshdhx.service.impl;
import java.io.IOException; import java.io.InputStream; import java.util.HashMap; import java.util.Map;
import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import com.pshdhx.pojo.PageInfo; import com.pshdhx.service.PeopleService;
public class PeopleServiceImpl implements PeopleService {
@Override public PageInfo showPage(int pageSize, int pageNumber) throws IOException { InputStream is = Resources.getResourceAsStream("mybatis.xml"); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is); SqlSession session = factory.openSession(); PageInfo pi = new PageInfo(); pi.setPageSize(pageSize); pi.setPageNumber(pageNumber); Map map.put("pageStart", pageSize*(pageNumber-1)); map.put("pageSize", pageSize);
pi.setList(session.selectList("a.b.selByPage",map));
long count = session.selectOne("a.b.selCount"); pi.setTotal(count%pageSize==0?count/pageSize:count/pageSize+1); return pi; }
} |
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> 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 heretitle> head> <body> <table border="1"> <tr> <th>编号th> <th>姓名th> <th>年龄th> tr> <c:forEach items="${PageInfo.list }" var="pi"> <tr> <td>${ pi.id}td> <td>${ pi.name}td> <td>${ pi.age}td> tr> c:forEach> table> <a href="page?pageNumber=${PageInfo.pageNumber-1 }&pageSize=${PageInfo.pageSize}" <c:if test="${PageInfo.pageNumber<=1 }"> οnclick="javascript:return false;" c:if>>上一页a> <a href="page?pageNumber=${PageInfo.pageNumber+1 }&pageSize=${PageInfo.pageSize}" <c:if test="${PageInfo.pageNumber>=PageInfo.total }"> οnclick="javascript:return false;" c:if>>下一页a> body> html> |
AccountMapper.xml |
xml version="1.0" encoding="UTF-8"?> DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="a.b">
<select id="selByAccnoPwd" resultType="account" parameterType="account"> select * from account where accno=#{accNo} and password=#{password} select>
<select id="selByAccnoName" resultType="account" parameterType="account"> select * from account where accno=#{accNo} and name=#{name} select>
<update id="updBalanceByAccno" parameterType="account"> update account set balance=balance+#{balance} where accno=#{accNo} update> mapper> |
loggerMapper.xml |
xml version="1.0" encoding="UTF-8"?> DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="a.Log"> <insert id="insLog" parameterType="log"> insert into log values(default,#{accOut},#{accIn},#{money}) insert> <select id="selByPage" resultType="log" parameterType="map"> select * from log limit #{pageStart},#{pageSize} select> <select id="selCount" resultType="long"> select count(*) from log select> mapper> |
Accountserviceimpl.java |
public int transfer(Account accIn, Account accOut) throws IOException { InputStream is = Resources.getResourceAsStream("mybatis.xml"); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is); SqlSession session = factory.openSession(); //先判断帐号和密码是否匹配 Account accOutSelect = session.selectOne("a.b.selByAccnoPwd",accOut); if(accOutSelect!=null){ if(accOutSelect.getBalance()>=accOut.getBalance()){ Account accInSelect = session.selectOne("a.b.selByAccnoName",accIn); if(accInSelect!=null){ accIn.setBalance(accOut.getBalance()); accOut.setBalance(-accOut.getBalance()); int index = session.update("a.b.updBalanceByAccno",accOut); index += session.update("a.b.updBalanceByAccno",accIn); if(index==2){ //日志表记录 Log log = new Log(); log.setAccIn(accIn.getAccNo()); log.setAccOut(accOut.getAccNo()); log.setMoney(accIn.getBalance()); session.insert("a.Log.insLog",log); //日志文件记录 Logger logger = Logger.getLogger(AccountServiceImpl.class); logger.info(log.getAccOut()+"给"+log.getAccIn()+"在"+new Date().
session.commit(); session.close(); return SUCCESS; }else{ session.rollback(); session.close(); return ERROR; } }else{ return ACCOUNT_NAME_NOT_MATCH; } }else{ //余额不足 return ACCOUNT_BALANCE_NOT_ENOUGH; } }else{ //帐号和密码不匹配 return ACCOUNT_PASSWORD_NOT_MATCH; } } |
Logserviceimpl.java
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package com.pshdhx.service.impl; /** * 这是后台的分页逻辑 */ import java.io.IOException; import java.io.InputStream; import java.util.HashMap; import java.util.List; import java.util.Map;
import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import com.pshdhx.pojo.Log; import com.pshdhx.pojo.PageInfo; import com.pshdhx.service.LogService;
public class LogServiceImpl implements LogService{
@Override public PageInfo showPage(int pageSize, int pageNumber) throws IOException { InputStream is = Resources.getResourceAsStream("mybatis.xml"); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is); SqlSession session = factory.openSession(); Map map.put("pageStart", pageSize*(pageNumber-1)); map.put("pageSize", pageSize);
List long count = session.selectOne("a.Log.selCount"); PageInfo pi = new PageInfo(); pi.setList(list); pi.setPageNumber(pageNumber); pi.setPageSize(pageSize); pi.setTotal(count%pageSize==0?count/pageSize:count/pageSize+1); return pi; }
} |
ShowlogServlet.java |
package com.pshdhx.servlet; /** * 此界面是对后台数据的显示,是后台对数据的响应操作,把数据表中的数据传递到前台,不需要name值,只要core,foreach即可 */ import java.io.IOException;
import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;
import com.pshdhx.service.LogService; import com.pshdhx.service.impl.LogServiceImpl; @WebServlet("/show") public class ShowServlet extends HttpServlet{
private LogService logService = new LogServiceImpl(); @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // TODO Auto-generated method stub int pageSize = 2; String pageSizeStr = req.getParameter("pageSize"); if(pageSizeStr!=null&&!pageSizeStr.equals("")){ pageSize =Integer.parseInt(pageSizeStr); } int pageNumber = 1; String pageNumberStr = req.getParameter("pageNumber"); if(pageNumberStr!=null&&!pageNumberStr.equals("")){ pageNumber = Integer.parseInt(pageNumberStr); }
//以上都是为了pageSize和pageNumber做准备,调用了serviceimpl的方法。 req.setAttribute("pageinfo", logService.showPage(pageSize, pageNumber)); req.getRequestDispatcher("/log.jsp").forward(req, resp); } } |
transferServlet.java |
package com.pshdhx.servlet; /** * 此界面是前台写数据,后台改变数据,是前台对后台的修改操作。对应的index.jsp中的form表单中都有name的属性值,方便操作。 */ import java.io.IOException;
import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession;
import com.pshdhx.pojo.Account; import com.pshdhx.service.AccountService; import com.pshdhx.service.impl.AccountServiceImpl; @WebServlet("/transfer") public class TransferServlet extends HttpServlet{ private AccountService accountService = new AccountServiceImpl(); @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // TODO Auto-generated method stub req.setCharacterEncoding("utf-8"); Account accOut = new Account(); accOut.setAccNo(req.getParameter("accOutAccNo")); accOut.setPassword(Integer.parseInt(req.getParameter("accOutPassword"))); accOut.setBalance(Double.parseDouble(req.getParameter("accOutBalance")));
Account accIn = new Account(); accIn.setAccNo(req.getParameter("accInAccNo")); accIn.setName(req.getParameter("accInName"));
//以上一切都是为了调用serviceimpl中的方法的参数做准备。此为方法的返回值,根据返回值判断执行的状态 int index = accountService.transfer(accIn, accOut);
//转账成功之后,服务器端会给出响应,跳转到 show界面 所以是 response if(index==AccountService.SUCCESS){ System.out.println("转账成功"); //resp.sendRedirect(req.getContextPath()+"/log.jsp"); resp.sendRedirect(req.getContextPath()+"/show"); }else{ HttpSession session = req.getSession(); session.setAttribute("code", index); resp.sendRedirect("/bank/error/error.jsp"); System.out.println("转账失败"); } } } |
public interface LogMapper { List List } |
xml version="1.0" encoding="UTF-8"?> DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.pshdhx.mapper.LogMapper"> <select id="selAll" resultType="Log"> select * from log select> <select id="selByAccInAccOut" resultType="Log" > select * from log where accin=#{param1} and accout=#{param2} select> mapper> |
package com.pshdhx.test;
import java.io.IOException; import java.io.InputStream; import java.util.List;
import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import com.pshdhx.mapper.LogMapper; import com.pshdhx.pojo.Log;
public class Test { public static void main(String[] args) throws IOException{ InputStream is = Resources.getResourceAsStream("mybatis.xml"); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is); SqlSession session = factory.openSession(); //实例化接口,初始化session.getMapper(接口); proxy代理模式 /** * 接口为什么实例化 ? * 需要给接口一个实例化对象 proxy jdk的动态代理模式,面向接口(必须有接口) * mybatis的好处:每次都要写session.selectList(里边的参数不用写了,更重要的是避免了多参数的问题转为map); */ LogMapper logMapper = session.getMapper(LogMapper.class); List for(Log log:list){ System.out.println(log); } System.out.println("--------------------------------------------"); List for(Log log:list2){ System.out.println(log); } session.close(); System.out.println("程序执行结束"); } } |
根据不同的条件需要执行不同的sql命令
在xml中添加逻辑判断
缓存的是statement对象,尽管sql语句一样,但是执行两次sql语句。