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我们在上一篇整合SpringBoot的基础之上，再进行本篇的实验。
总体思路是将实体对象转成map后传给mybatis去执行，将mybatis的执行结果由map转成实体对象后输出。
首先CommDao.xml
insert into ${db.tableName} values ${key} #{val} delete from ${db.tableName} where ${db.primaryKeyName}=#{params.${db.primaryKeyName}} update ${db.tableName} set where ${db.primaryKeyName} =#{params.${db.primaryKeyName}} ${key}= #{params.${key}}
CommDao
package com.yj.dao;import java.util.Map;import org.apache.ibatis.annotations.Param;import org.springframework.stereotype.Repository;import com.yj.comm.model.DbProperties;@Repositorypublic interface CommDao { void insert(@Param("params") Map map, @Param("db") DbProperties dbProperties); void deleteByPrimaryKey(@Param("params") Map map, @Param("db") DbProperties dbProperties); void updateByPrimaryKey(@Param("params") Map map, @Param("db") DbProperties dbProperties); Map selectByPrimaryKey(@Param("params") Map map, @Param("db") DbProperties dbProperties);} DbProperties
package com.yj.comm.model;import java.io.Serializable;/** * @param tableName 表名 * @param primaryKeyName 库表的主键名称 */public class DbProperties implements Serializable { private static final long serialVersionUID = 2134017968462962008L; private String tableName; private String primaryKeyName; public String getTableName() { return tableName; } public void setTableName(String tableName) { this.tableName = tableName; } public String getPrimaryKeyName() { return primaryKeyName; } public void setPrimaryKeyName(String primaryKeyName) { this.primaryKeyName = primaryKeyName; }} User
package com.yj.model;public class User{ private Integer id; private String name; private Integer age; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name == null ? null : name.trim(); } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } @Override public String toString() { return "User [id=" + id + ", name=" + name + ", age=" + age + "]"; }} CommService
package com.yj.service;import java.io.IOException;import java.util.Map;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import com.yj.comm.model.DbProperties;import com.yj.comm.util.CommUtil;import com.yj.dao.CommDao;@Servicepublic class CommService { @Autowired private CommDao commDao; public void insert(Object object, DbProperties dbProperties) { Map map = CommUtil.objectToMap(object); commDao.insert(map, dbProperties); } public void deleteByPrimaryKey(Object object, DbProperties dbProperties) { Map map = CommUtil.objectToMap(object); commDao.deleteByPrimaryKey(map, dbProperties); } public void updateByPrimaryKey(Object object, DbProperties dbProperties) { Map map = CommUtil.objectToMap(object); commDao.updateByPrimaryKey(map, dbProperties); } public Object selectByPrimaryKey(Object object, DbProperties dbProperties) throws IOException { Map map = CommUtil.objectToMap(object); map=commDao.selectByPrimaryKey(map, dbProperties); return CommUtil.mapToObject(map, object.getClass()); }} CommUtil
package com.yj.comm.util;import java.beans.BeanInfo;import java.beans.Introspector;import java.beans.PropertyDescriptor;import java.lang.reflect.Method;import java.sql.Timestamp;import java.text.SimpleDateFormat;import java.util.HashMap;import java.util.Map;import java.util.regex.Matcher;import java.util.regex.Pattern;import com.alibaba.fastjson.JSON;public class CommUtil { private static Pattern pattern = Pattern.compile("_(\\w)"); private static SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); public static String camelToUnderline(String str) { int len = str.length(); StringBuilder sb = new StringBuilder(len); for (int i = 0; i < len; i++) { char c = str.charAt(i); if (Character.isUpperCase(c)) { sb.append("_"); sb.append(Character.toLowerCase(c)); } else { sb.append(c); } } return sb.toString(); } public static String underlineToCamel(String str) { str = str.toLowerCase(); final StringBuffer sb = new StringBuffer(); Matcher m = pattern.matcher(str); while (m.find()) { m.appendReplacement(sb, m.group(1).toUpperCase()); } m.appendTail(sb); return sb.toString(); } public static Map objectToMap(Object bean) { Map returnMap = null; try { Class type = bean.getClass(); returnMap = new HashMap (); BeanInfo beanInfo = Introspector.getBeanInfo(type); PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors(); for (int i = 0; i < propertyDescriptors.length; i++) { PropertyDescriptor descriptor = propertyDescriptors[i]; String propertyName = descriptor.getName(); if (!propertyName.equals("class")) { Method readMethod = descriptor.getReadMethod(); Object result = readMethod.invoke(bean, new Object[0]); if (result != null) { returnMap.put(CommUtil.camelToUnderline(propertyName), result); } else { returnMap.put(CommUtil.camelToUnderline(propertyName), ""); } } } } catch (Exception e) { e.printStackTrace(); } return returnMap; } public static T mapToObject(Map map, Class clazz) { T result = null; Map dataMap = new HashMap<>(); for (Map.Entry entry : map.entrySet()) { String key = CommUtil.underlineToCamel(entry.getKey()); Object value = entry.getValue(); if (value instanceof Timestamp) { value = format.format(value); } dataMap.put(key, value); } String json = JSON.toJSONString(dataMap); result = JSON.parseObject(json, clazz); return result; }} 准备完毕，我们进行单元测试
CommServiceTest
package com.yj.service;import java.io.IOException;import org.junit.Test;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Autowired;import com.yj.ApplicationTest;import com.yj.comm.model.DbProperties;import com.yj.model.User;public class CommServiceTest extends ApplicationTest{ private Logger log = LoggerFactory.getLogger(this.getClass()); @Autowired private CommService commService; @Test public void insert() { User user =new User(); user.setName("test1"); user.setAge(18); DbProperties dbProperties=new DbProperties(); dbProperties.setPrimaryKeyName("id"); dbProperties.setTableName("user"); commService.insert(user, dbProperties); } @Test public void deleteByPrimaryKey() { User user =new User(); user.setId(14); DbProperties dbProperties=new DbProperties(); dbProperties.setPrimaryKeyName("id"); dbProperties.setTableName("user"); commService.deleteByPrimaryKey(user, dbProperties); } @Test public void updateByPrimaryKey() { User user =new User(); user.setId(13); user.setName("aaa"); user.setAge(19); DbProperties dbProperties=new DbProperties(); dbProperties.setPrimaryKeyName("id"); dbProperties.setTableName("user"); commService.updateByPrimaryKey(user, dbProperties); } @Test public void selectByPrimaryKey() throws IOException { User user =new User(); user.setId(13); DbProperties dbProperties=new DbProperties(); dbProperties.setPrimaryKeyName("id"); dbProperties.setTableName("user"); User result=(User) commService.selectByPrimaryKey(user, dbProperties); log.info("result:"+result); }} 基于动态SQL的最基本增删改查的操作成功
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