Mybatis如何自動(dòng)生成數(shù)據(jù)庫(kù)表結(jié)構(gòu)總結(jié)

更新時(shí)間：2019年11月02日 10:14:03 作者：Dream Young

這篇文章主要給大家介紹了關(guān)于Mybatis如何自動(dòng)生成數(shù)據(jù)庫(kù)表結(jié)構(gòu)的相關(guān)資料，文中通過(guò)示例代碼介紹的非常詳細(xì)，對(duì)大家的學(xué)習(xí)或者使用Mybatis具有一定的參考學(xué)習(xí)價(jià)值，需要的朋友們下面來(lái)一起學(xué)習(xí)學(xué)習(xí)吧

一般情況下，用Mybatis的時(shí)候是先設(shè)計(jì)表結(jié)構(gòu)再進(jìn)行實(shí)體類(lèi)以及映射文件編寫(xiě)的，特別是用代碼生成器的時(shí)候。

但有時(shí)候不想用代碼生成器，也不想定義表結(jié)構(gòu)，那怎么辦？

這個(gè)時(shí)候就會(huì)想到Hibernate，然后想到它的hibernate.hbm2ddl.auto配置項(xiàng)。

所以手工創(chuàng)表的問(wèn)題可以很方便的迅速用Hibernate來(lái)解決。那有人問(wèn)啦：就是不想用Hibernate才換的Mybatis，你這又兜回去了嗎？

其實(shí)不是的，我們需要的就是單單一個(gè)hbm2ddl功能。

其實(shí)應(yīng)該這么想：有一款工具能夠自動(dòng)根據(jù)注解的實(shí)體類(lèi)來(lái)生成各種數(shù)據(jù)庫(kù)相應(yīng)的表結(jié)構(gòu)，只需要加幾個(gè)jar包 (經(jīng)測(cè)試后只要7個(gè)）并且 少量配置(3個(gè)配置項(xiàng)） 。

這款工具就是Hibernate。為什么不能是它呢?。?！

原理說(shuō)來(lái)也是超級(jí)的簡(jiǎn)單：加入hibernate的包，注解實(shí)體類(lèi)，程序開(kāi)始時(shí)初始化一下hibernate的SessionFactory并清除它。

示例：

需要的Hibernate相關(guān)的JAR包 (本例基于Hibernate5.0.7，僅需要7個(gè)）：

hibernate-core-5.0.7.Final.jar

hibernate-commons-annotations-5.0.1.Final.jar

hibernate-jpa-2.1-api-1.0.0.Final.jar

geronimo-jta_1.1_spec-1.1.1.jar

jboss-logging-3.3.0.Final.jar

dom4j-1.6.1.jar

javassist-3.18.1-GA.jar

Hibernate.cfg.xml文件：（去掉多余的，精簡(jiǎn)后的內(nèi)容）

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
 "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
 "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
 <session-factory>
  <!--不采用InnoDB方式加快速度 -->
  <property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>

  <!-- 注意update方式時(shí)對(duì)于屬性的刪減并不會(huì)刪除數(shù)據(jù)庫(kù)字段 -->
  <property name="hibernate.hbm2ddl.auto">update</property>

  <!-- 注意注解的話，只能用class一個(gè)一個(gè)引用。除非與Spring整合才能掃描文件夾路徑 -->
  <mapping class="com.sunwii.mybatis.bean.User" />
 </session-factory>
</hibernate-configuration>

注解的實(shí)體類(lèi)：

@Entity
@Table(name = "t_user")
@Data
@NoArgsConstructor
@ToString
public class User implements Serializable {
 private static final long serialVersionUID = -4013951528313410972L;

 @Id
 @GeneratedValue(strategy = GenerationType.IDENTITY)
 @Column(name = "id")
 private Integer id;

 @Column(length = 30)
 private String name;

 @Column
 private Float height;

 @Column
 private Double salary;

 @Column
 private Integer vip;

 @Column
 @Temporal(TemporalType.DATE)
 private Date birthday;

 @Column
 @Temporal(TemporalType.TIMESTAMP)
 private Date lastlogin;

 @Column
 @Enumerated(EnumType.STRING)
 // mybatis 默認(rèn)會(huì)將枚舉轉(zhuǎn)化為字符串類(lèi)型存儲(chǔ),此時(shí)數(shù)據(jù)庫(kù)為varchar型
 private State state;
 
 @Column
 @Enumerated(EnumType.ORDINAL)
 // 可以為mybatis設(shè)置枚舉類(lèi)型存儲(chǔ)為其索引值存儲(chǔ)，此時(shí)數(shù)據(jù)庫(kù)為int型
 private Level level;

 @Column(length = 10)
 @Enumerated(EnumType.ORDINAL)
 // mybatis 自定義類(lèi)型轉(zhuǎn)換器將枚舉轉(zhuǎn)化為相應(yīng)數(shù)字類(lèi)型存儲(chǔ)，此時(shí)數(shù)據(jù)庫(kù)為int型
 private Sex sex;
 
 @Column
 @Type(type = "string")
 // mybatis 自定義類(lèi)型轉(zhuǎn)換器將列表轉(zhuǎn)化為相應(yīng)字符串類(lèi)型存儲(chǔ)，此時(shí)數(shù)據(jù)庫(kù)為varchar型
 private List<String> tels;
 

 public User(int id) {
  super();
  this.id = id;
 }

 public User(int id, String name) {
  super();
  this.id = id;
  this.name = name;
 }

 public User(String name) {
  super();
  this.name = name;
 }
}

注意：以上實(shí)體類(lèi)用了Lombok插件來(lái)減少代碼量（只要是為了不寫(xiě)setter/getter、toString等。Lombok插件的使用請(qǐng)參考其它地方。）

@Data

@NoArgsConstructor

@ToString

三個(gè)注解屬于Lombok插件注解，分別指示生成SETTER/GETTER、生成無(wú)參構(gòu)造器、生成ToString

其它注解都屬于Hibernate（JPA規(guī)范）的注解，生成DDL就靠它們了。

注解-說(shuō)明：

@Entity
@Table(name = "t_user")
這里指實(shí)體類(lèi)對(duì)應(yīng)了t_user表

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
這里指表主健自動(dòng)增長(zhǎng)

@Column
這里指表字段名稱與屬性同名,它可以另外指定長(zhǎng)度，名稱。
@Temporal(TemporalType.DATE)
這里指表字段采用Date類(lèi)型存儲(chǔ)
@Enumerated(EnumType.STRING)
這里指表字段采用varchar類(lèi)型來(lái)存儲(chǔ)枚舉屬性



這個(gè)簡(jiǎn)短示例僅列出簡(jiǎn)單的類(lèi)型的注解，并不涉及表關(guān)聯(lián)之間的注解，幸好的是，注解并不多，更多注解可以參考Hibernate(JPA)注解相關(guān)內(nèi)容。

至此，只需要在使用SqlSessionFactory（Mybatis）之前就構(gòu)造SessionFactory（Hibernate）然后銷(xiāo)毀它就可以了。至于如何初始化Hibernate的SessionFactory，應(yīng)該都知道。如下：

Mybatis與Spring整合時(shí)：簡(jiǎn)單地配置一個(gè)hibernate的SessionFactory相關(guān)的BEAN了事。這里不談。

Mybatis不與Spring整合時(shí)：

Mybatis的工具類(lèi)中添加新方法，用于自動(dòng)構(gòu)造DDL：

package com.sunwii.mybatis.util;

import java.io.IOException;
import java.io.InputStream;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import com.sunwii.mybatis.constant.Constants;

public class SessionFactoryUtil {
 public static SqlSessionFactory creat(String configFile) {

  SqlSessionFactory factory = null;
  InputStream inputStream;
  try {
   inputStream = Resources.getResourceAsStream(configFile);
   factory = new SqlSessionFactoryBuilder().build(inputStream);
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  return factory;
 }

 //這里是新方法，通過(guò)判斷標(biāo)記決定是否要用于自動(dòng)生成DDL
 public static SqlSessionFactory creat(String configFile, boolean hibernateAutoDdl) {
  if (hibernateAutoDdl) {
   String hibernateConfigFile = Constants.Hibernate_LOCATION;
   // 使用hibernate自動(dòng)創(chuàng)建DDL
   HibernateUtil.buildSessionFactory(hibernateConfigFile);
  }

  return creat(configFile);
 }
}

其中用到的Hibernate工具類(lèi)為：

package com.sunwii.mybatis.util;

import java.util.Properties;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

import com.sunwii.mybatis.constant.Constants;

public class HibernateUtil {
 public static void buildSessionFactory(String hibernateConfigFile) {
  String jdbcPropertiesLocation = Constants.JDBC_LOCATION;
  Properties jdbcProperties = PropertiesUtil.loadFromClassPath(jdbcPropertiesLocation);

  Properties hibernateJdbcProperties = new Properties();
  hibernateJdbcProperties.setProperty("hibernate.connection.driver_class", jdbcProperties.getProperty("driver"));
  hibernateJdbcProperties.setProperty("hibernate.connection.url", jdbcProperties.getProperty("url"));
  hibernateJdbcProperties.setProperty("hibernate.connection.username", jdbcProperties.getProperty("user"));
  hibernateJdbcProperties.setProperty("hibernate.connection.password", jdbcProperties.getProperty("password"));

  final Configuration cfg = new Configuration();
  cfg.addProperties(hibernateJdbcProperties);
  cfg.configure(hibernateConfigFile);
  SessionFactory sessionFactory = cfg.buildSessionFactory();

  // 啟動(dòng)后銷(xiāo)毀
  sessionFactory.close();
  sessionFactory = null;

 }

}

PropertiesUtil工具類(lèi)：

package com.sunwii.mybatis.util;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

public class PropertiesUtil {
 public static Properties loadFromClassPath(String fileName) {
  Properties props = new Properties();
  while(fileName!=null && fileName.length()>0 && (fileName.startsWith("/") || fileName.startsWith("\\"))) {
   fileName = fileName.substring(1);
  }
  InputStream is = Class.class.getResourceAsStream("/"+fileName);
  try {
   props.load(is);
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  return props;
 }
}

常量配置類(lèi)Constant:

package com.sunwii.mybatis.constant;

public class Constants {
 public static String JDBC_LOCATION = "jdbc.properties";
 public static String Hibernate_LOCATION = "hibernate.cfg.xml";
}

Mybatis配置文件：

<?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>
 <!-- 別名 -->
 <typeAliases>
  <!-- 指定包下所有別名為類(lèi)名的簡(jiǎn)名 -->
  <package name="com.sunwii.mybatis.bean" />
 </typeAliases>

 <!-- 類(lèi)型處理器 -->
 <typeHandlers>
  <!-- 改變默認(rèn)處理枚舉(枚舉轉(zhuǎn)換為int) -->
  <typeHandler
   handler="org.apache.ibatis.type.EnumOrdinalTypeHandler"
   javaType="com.sunwii.mybatis.enums.Level" />

  <!-- 自定義處理枚舉(枚舉轉(zhuǎn)換為枚舉鍵值對(duì)的數(shù)字值) -->
  <typeHandler
   handler="com.sunwii.mybatis.typehandle.SexEnumTypeHandler"
   javaType="com.sunwii.mybatis.enums.Sex" />

  <!-- 自定義處理列表(列表轉(zhuǎn)換為字符串連接) -->
  <!-- 注意，由于是非內(nèi)置的轉(zhuǎn)換類(lèi)型，所以僅對(duì)select有效,insert/update/delete需要另行指定 -->
  <!-- 另行指定示例：${tels,typeHandler=com.sunwii.mybatis.typehandle.ListTypeHandler} -->
  <typeHandler
   handler="com.sunwii.mybatis.typehandle.ListTypeHandler"
   javaType="java.util.List" />
 </typeHandlers>


 <environments default="development">
  <environment id="development">
   <transactionManager type="JDBC" />
   <!-- 自定義MyPoolDataSourceFactory簡(jiǎn)化配置 -->
   <dataSource type="com.sunwii.mybatis.pool.MyPoolDataSourceFactory" />
  </environment>
 </environments>

 <mappers>
  <package name="com/sunwii/mybatis/mapper" />
 </mappers>
</configuration>

連接池裝飾類(lèi)（用于簡(jiǎn)化Mybatis配置并統(tǒng)一jdbc配置文件路徑常量）：

package com.sunwii.mybatis.pool;

import java.util.Properties;

import org.apache.ibatis.datasource.pooled.PooledDataSource;
import org.apache.ibatis.datasource.pooled.PooledDataSourceFactory;

import com.sunwii.mybatis.constant.Constants;
import com.sunwii.mybatis.util.PropertiesUtil;

public class MyPoolDataSourceFactory extends PooledDataSourceFactory {
 public MyPoolDataSourceFactory() {
  PooledDataSource dataSource = new PooledDataSource();

  // 更多屬性可以通過(guò)<property>來(lái)設(shè)置。 
  String jdbcPropertiesFile = Constants.JDBC_LOCATION;
  Properties prop = PropertiesUtil.loadFromClassPath(jdbcPropertiesFile);

  dataSource.setDriver(prop.getProperty("driver"));
  dataSource.setUrl(prop.getProperty("url"));
  dataSource.setUsername(prop.getProperty("user"));
  dataSource.setPassword(prop.getProperty("password")); 
  this.dataSource = dataSource;
 }

}

用到的幾個(gè)枚舉類(lèi)：

package com.sunwii.mybatis.enums;

public enum Level {
 LEVEL_0, 
 LEVEL_1, 
 LEVEL_2, 
 LEVEL_3, 
 LEVEL_4, 
 LEVEL_5
}


package com.sunwii.mybatis.enums;

import java.util.HashMap;

public enum Sex {
 MAN("男", 0), WOMAN("女", 1);

 private String key;
 public String getKey() {
  return key;
 }

 public void setKey(String key) {
  this.key = key;
 }

 public Integer getValue() {
  return value;
 }

 public void setValue(Integer value) {
  this.value = value;
 }

 private Integer value;

 private static HashMap<Integer, Sex> valueMap = new HashMap<Integer, Sex>();
 private static HashMap<String, Sex> keyMap = new HashMap<String, Sex>();

 static {
  for (Sex item : Sex.values()) {
   valueMap.put(item.value, item);
   keyMap.put(item.key, item);
  }
 }

 Sex(String key, Integer value) {
  this.key = key;
  this.value = value;
 }

 public static Sex getByValue(int value) {
  Sex result = valueMap.get(value);
  return result;
 }

 public static Sex getByKey(String key) {
  Sex result = keyMap.get(key);
  return result;
 }
}


package com.sunwii.mybatis.enums;

public enum State {
 OK, ERROR, UNKNOWN
}

用到的類(lèi)型轉(zhuǎn)換器：

package com.sunwii.mybatis.typehandle;

import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandler;

import com.sunwii.mybatis.enums.Sex;

/**
 * -必須實(shí)現(xiàn)所有方法，不然的話查詢有可能查詢到為null
 * @author Administrator
 *
 */
public class SexEnumTypeHandler implements TypeHandler<Sex> {

 /**
  * 轉(zhuǎn)換到數(shù)據(jù)庫(kù)的值
  */
 @Override
 public void setParameter(PreparedStatement ps, int i, Sex parameter, JdbcType jdbcType) throws SQLException {
  ps.setInt(i, parameter.getValue());
 }

 /**
  * 從數(shù)據(jù)庫(kù)轉(zhuǎn)換得到
  */
 @Override
 public Sex getResult(ResultSet rs, String columnName) throws SQLException {
  return Sex.getByValue(rs.getInt(columnName));
 }

 /**
  * 從數(shù)據(jù)庫(kù)轉(zhuǎn)換得到
  */
 @Override
 public Sex getResult(ResultSet rs, int columnIndex) throws SQLException {
  return Sex.getByValue(rs.getInt(columnIndex));
 }

 /**
  * 從數(shù)據(jù)庫(kù)轉(zhuǎn)換得到
  */
 @Override
 public Sex getResult(CallableStatement cs, int columnIndex) throws SQLException {
  return Sex.getByValue(cs.getInt(columnIndex));
 }

}

package com.sunwii.mybatis.typehandle;

import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.List;

import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandler;

import com.sunwii.mybatis.util.ArrayUtil;

/**
 * -必須實(shí)現(xiàn)所有方法，不然的話查詢有可能查詢到為null
 * @author Administrator
 *
 */
public class ListTypeHandler implements TypeHandler<List<?>> {

 @SuppressWarnings({ "unchecked", "rawtypes" })
 @Override
 public void setParameter(PreparedStatement ps, int i, List parameter, JdbcType jdbcType) throws SQLException {
  String[] strArr = ArrayUtil.fromList((List<String>) parameter);
  String strs = ArrayUtil.asString(",", strArr);
  ps.setString(i, strs);
 }

 @Override
 public List<String> getResult(ResultSet rs, String columnName) throws SQLException {
  List<String> list = null;
  String strs = rs.getString(columnName);
  if (strs != null && strs.length() > 0) {
   list = Arrays.asList(strs.split(","));
  }
  return list;
 }

 @Override
 public List<String> getResult(ResultSet rs, int columnIndex) throws SQLException {
  List<String> list = null;
  String strs = rs.getString(columnIndex);
  if (strs != null && strs.length() > 0) {
   list = Arrays.asList(strs.split(","));
  }
  return list;
 }

 @Override
 public List<String> getResult(CallableStatement cs, int columnIndex) throws SQLException {
  List<String> list = null;
  String strs = cs.getString(columnIndex);
  if (strs != null && strs.length() > 0) {
   list = Arrays.asList(strs.split(","));
  }
  return list;
 }

}

用到的數(shù)組集合轉(zhuǎn)換工具類(lèi)：

package com.sunwii.mybatis.util;

import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class ArrayUtil {
 @SuppressWarnings("unchecked")
 public static <T> List<T> asList(T... args) {
  return Arrays.asList(args);
 }

 public static <T> List<T> asListFromSet(Set<T> set) {
  if (set == null || set.size() < 1) {
   return null;
  }
  List<T> list = new ArrayList<T>();
  for (T t : set) {
   list.add(t);
  }

  return list;
 }

 public static <T> List<T> asListFromArray(T[] array) {
  if (array == null || array.length < 1) {
   return null;
  }
  List<T> list = new ArrayList<T>();
  for (T t : array) {
   list.add(t);
  }

  return list;
 }

 public static <T> List<T> asListFromMapKey(Map<T, ?> map) {
  if (map == null || map.size() < 1) {
   return null;
  }

  return ArrayUtil.asListFromSet(map.keySet());
 }

 public static <T> List<T> asListFromMapValue(Map<?, T> map) {
  if (map == null || map.size() < 1) {
   return null;
  }

  List<T> list = new ArrayList<T>();
  Collection<T> values = map.values();
  for (T t : values) {
   list.add(t);
  }
  return list;
 }

 @SuppressWarnings("unchecked")
 public static <T> T[] fromArray(T... args) {
  if (args == null || args.length < 1) {
   return null;
  }

  T[] array = (T[]) Array.newInstance(args[0].getClass(), args.length);

  for (int i = 0; i < args.length; i++) {
   array[i] = args[i];
  }

  return array;
 }

 @SuppressWarnings("unchecked")
 public static <T> T[] fromList(List<T> list) {
  if (list == null || list.size() < 1) {
   return null;
  }

  Class<T> clz = null;
  for (T t : list) {
   clz = (Class<T>) t.getClass();
   break;
  }

  T[] array = (T[]) Array.newInstance(clz, list.size());

  int i = 0;
  for (T t : list) {
   array[i] = t;
   i++;
  }

  return array;
 }

 @SuppressWarnings("unchecked")
 public static <T> T[] fromSet(Set<T> set) {
  if (set == null || set.size() < 1) {
   return null;
  }

  Class<T> clz = null;
  for (T t : set) {
   clz = (Class<T>) t.getClass();
   break;
  }

  T[] array = (T[]) Array.newInstance(clz, set.size());

  int i = 0;
  for (T t : set) {
   array[i] = t;
   i++;
  }

  return array;
 }

 public static <T> T[] fromMapKey(Map<T, ?> map) {
  if (map == null || map.size() < 1) {
   return null;
  }

  Set<T> set = map.keySet();

  return ArrayUtil.fromSet(set);
 }

 public static <T> T[] fromMapValue(Map<?, T> map) {
  if (map == null || map.size() < 1) {
   return null;
  }

  List<T> list = new ArrayList<T>();
  Collection<T> values = map.values();
  for (T t : values) {
   list.add(t);
  }
  return ArrayUtil.fromList(list);
 }

 @SuppressWarnings("unchecked")
 public static <T> Set<T> asSet(T... args) {
  if (args == null || args.length < 1) {
   return null;
  }
  Set<T> set = new HashSet<T>();
  for (int i = 0; i < args.length; i++) {
   if (!set.contains(args[i])) {
    set.add(args[i]);
   }
  }

  return set;
 }

 public static <T> Set<T> asSetFromArray(T[] array) {
  if (array == null || array.length < 1) {
   return null;
  }
  Set<T> set = new HashSet<T>();
  for (T t : array) {
   set.add(t);
  }

  return set;
 }

 public static <T> Set<T> asSetFromMapKey(Map<T, ?> map) {
  if (map == null || map.size() < 1) {
   return null;
  }

  return map.keySet();
 }

 public static <T> Set<T> asSetFromMapValue(Map<?, T> map) {
  if (map == null || map.size() < 1) {
   return null;
  }

  Set<T> set = new HashSet<T>();
  Collection<T> values = map.values();
  for (T t : values) {
   set.add(t);
  }
  return set;
 }

 public static <T1, T2> Map<T1, T2> asMapFrom(Set<T1> keySet, Set<T2> valueSet) {
  if (keySet == null || keySet.size() < 1 || valueSet == null || valueSet.size() < 1) {
   return null;
  }

  Map<T1, T2> map = new HashMap<T1, T2>();
  List<T2> list = ArrayUtil.asListFromSet(valueSet);
  int i = 0;
  for (T1 t : keySet) {
   try {
    map.put(t, list.get(i++));
   } catch (Exception e) {// 超長(zhǎng)
    map.put(t, null);
   }
  }

  return map;
 }

 @SuppressWarnings("unchecked")
 public static <T> String asString(String separator, T... args) {
  if (args == null || args.length < 1) {
   return null;
  }
  StringBuilder sp = new StringBuilder();
  for (int i = 0; i < args.length; i++) {

   sp.append(args[i]);
   if (i != args.length - 1) {
    sp.append(separator);
   }
  }

  return sp.toString();
 }
}

Mapper接口：UserMapper.java

package com.sunwii.mybatis.mapper;

import java.util.List;

import com.sunwii.mybatis.bean.User;

public interface UserMapper {
 public User selectById(int id);

 public List<User> selectByName(String name);

 public int insert(User user);

 public int update(User user);

 public int delete(int id);
}

映射文件：UserMapper.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="com.sunwii.mybatis.mapper.UserMapper">
 <select id="selectById" parameterType="Integer"
  resultType="User">
  select * from t_user where id = #{id}
 </select>

 <select id="selectByName" parameterType="String"
  resultType="User">
  select * from t_user where name like "%"#{name}"%"
 </select>

 <insert id="insert">
  insert into
  t_user(
  name, birthday, vip, salary, height, lastlogin,level,state,sex,tels
  )values(
  #{name},
  #{birthday},
  #{vip},
  #{salary},
  #{height},
  #{lastlogin},
  #{level},
  #{state},
  #{sex},
  #{tels,typeHandler=com.sunwii.mybatis.typehandle.ListTypeHandler}
  )
 </insert>

 <update id="update">
  update t_user set
  name=#{name},
  birthday=#{birthday},
  vip=#{vip},
  salary=#{salary},
  height=#{height},
  lastlogin=#{lastlogin},
  level=#{level},
  state=#{state},
  sex=#{sex},
  tels=#{tels,typeHandler=com.sunwii.mybatis.typehandle.ListTypeHandler}
  where id=#{id}
 </update>

 <delete id="delete" parameterType="Integer">
  delete from t_user where
  id=#{id}
 </delete>
</mapper>

日期工具：CurrentUtil.java

package com.sunwii.mybatis.util;

import java.sql.Timestamp;
import java.util.Date;

public class CurrentUtil {
  public static long currentTime() {
    return new Date().getTime();
  }

  public static Date currentDate() {
    return new Date();
  }

  public static java.sql.Date currentSqlDate() {
    return new java.sql.Date(currentTime());
  }

  public static Timestamp currentTimestamp() {
    return new java.sql.Timestamp(currentTime());
  }
}

測(cè)試示例：

package com.sunwii.mybatis.test.mapper;

import java.util.Arrays;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.junit.Test;

import com.sunwii.mybatis.bean.User;
import com.sunwii.mybatis.enums.Level;
import com.sunwii.mybatis.enums.Sex;
import com.sunwii.mybatis.enums.State;
import com.sunwii.mybatis.mapper.UserMapper;
import com.sunwii.mybatis.test.insert.TestInsert;
import com.sunwii.mybatis.util.CurrentUtil;
import com.sunwii.mybatis.util.SessionFactoryUtil;

public class testMapper {
  private static Log log = LogFactory.getLog(TestInsert.class);
  private static SqlSessionFactory sf = SessionFactoryUtil.creat("mybatis-config.xml", true);

  @Test
  public void testMapperInsert() {
    User user = new User();
    //user.setId(50);
    user.setName("sunwii");
    user.setVip(1);
    user.setSalary(3333.00);
    user.setHeight(1.70f);
    user.setBirthday(CurrentUtil.currentDate());
    user.setLastlogin(CurrentUtil.currentTimestamp());
    user.setLevel(Level.LEVEL_3);
    user.setState(State.OK);
    user.setSex(Sex.WOMAN);
    user.setTels(Arrays.asList("133xxxxxxx", "159xxxxxxxx"));

    int rs = 0;
    SqlSession session = sf.openSession();
    UserMapper userMapper = session.getMapper(UserMapper.class);
    try {
      rs = userMapper.insert(user);
      session.commit();
    } catch (Exception e) {
      rs = 0;
      session.rollback();
      e.printStackTrace();
    } finally {
      session.close();
    }

    log.info("操作結(jié)果：" + rs);

  }

  @Test
  public void testMapperUpdate() {
    User user = new User();
    user.setId(1);
    user.setName("sunwii--55550");
    user.setVip(1);
    user.setSalary(3333.00);
    user.setHeight(1.70f);
    user.setBirthday(CurrentUtil.currentDate());
    user.setLastlogin(CurrentUtil.currentTimestamp());
    user.setLevel(Level.LEVEL_2);
    user.setState(State.ERROR);
    user.setSex(Sex.MAN);
    user.setTels(Arrays.asList("136xxxxxx", "139xxxxxxx"));

    int rs = 0;
    SqlSession session = sf.openSession();
    UserMapper userMapper = session.getMapper(UserMapper.class);
    try {
      rs = userMapper.update(user);
      session.commit();
    } catch (Exception e) {
      rs = 0;
      session.rollback();
      e.printStackTrace();
    } finally {
      session.close();
    }

    log.info("操作結(jié)果：" + rs);

  }

  @Test
  public void testMapperDelete() {
    User user = new User(50);

    int rs = 0;
    SqlSession session = sf.openSession();
    UserMapper userMapper = session.getMapper(UserMapper.class);
    try {
      rs = userMapper.delete(user.getId());
      session.commit();
    } catch (Exception e) {
      rs = 0;
      session.rollback();
      e.printStackTrace();
    } finally {
      session.close();
    }

    log.info("操作結(jié)果：" + rs);

  }

  @Test
  public void testMapperGetOne() {
    Integer id = 50;
    User user = null;
    SqlSession session = sf.openSession();
    UserMapper userMapper = session.getMapper(UserMapper.class);
    user = userMapper.selectById(id);

    log.info(user);

  }

  @Test
  public void testMapperGetList() {
    String userName = "sunwii";

    List<User> users = null;
    SqlSession session = sf.openSession();
    UserMapper userMapper = session.getMapper(UserMapper.class);
    users = userMapper.selectByName(userName);

    for (User user : users) {
      log.info(user);
    }

  }
}

<<Mybatis總結(jié)之如何自動(dòng)生成數(shù)據(jù)庫(kù)表結(jié)構(gòu)>>

說(shuō)明：

這里多余的步驟僅僅是為了存檔下代碼（以及方便一些初學(xué)者不看代碼不知道怎么回事的原因:里邊涉及了各種常用類(lèi)型的轉(zhuǎn)換和映射）。

本文中最重要的就是Hibernate的幾個(gè)包的選取，以及配置文件的精簡(jiǎn)，還有就是加載Hibernate的SessionFactory的方法。

這些說(shuō)來(lái)說(shuō)去都是Hibernate的東西。跟Mybatis原本是沒(méi)有一點(diǎn)關(guān)系的。只不過(guò)需要用于，那純屬相當(dāng)于復(fù)習(xí)一下Hibernate了。

總結(jié)

以上就是這篇文章的全部?jī)?nèi)容了，希望本文的內(nèi)容對(duì)大家的學(xué)習(xí)或者工作具有一定的參考學(xué)習(xí)價(jià)值，謝謝大家對(duì)腳本之家的支持。

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