int countByExample(UserExample example); //下面是一個(gè)完整的案列UserExample example = new UserExample(); Criteria criteria = example.createCriteria(); criteria.andUsernameEqualTo("joe"); int count = userDAO.countByExample(example);

int deleteByExample(AccountExample example); //下面是一個(gè)完整的案例UserExample example = new UserExample(); Criteria criteria = example.createCriteria(); criteria.andUsernameEqualTo("joe"); userDAO.deleteByExample(example); 相當(dāng)于：delete from user where username='joe'

int deleteByPrimaryKey(Integer id);userDAO.deleteByPrimaryKey(101); 

delete from user where id=101 

int insert(Account record); //下面是完整的案例User user = new User(); //user.setId(101); user.setUsername("test"); user.setPassword("123456") user.setEmail("674531003@qq.com"); userDAO.insert(user);

insert into user(ID,username,password,email) values(101,'test','123456','674531003@qq.com');

int insertSelective(Account record);

List<Account> selectByExample(AccountExample example); //下面是一個(gè)完整的案例UserExample example = new UserExample();Criteria criteria = example.createCriteria();criteria.andUsernameEqualTo("joe");criteria.andUsernameIsNull();example.setOrderByClause("username asc,email desc");List<?>list = userDAO.selectByExample(example);相當(dāng)于：select * from user where username = 'joe' and username is null order by username asc,email desc //注：在iBator 生成的文件UserExample.java中包含一個(gè)static 的內(nèi)部類 Criteria ，在Criteria中有很多方法，主要是定義SQL 語句where后的查詢條件。

Account selectByPrimaryKey(Integer id);//相當(dāng)于select * from user where id = 變量id

int updateByExampleSelective(@Param("record") Account record, @Param("example") AccountExample example); //下面是一個(gè)完整的案列UserExample example = new UserExample(); Criteria criteria = example.createCriteria(); criteria.andUsernameEqualTo("joe"); User user = new User(); user.setPassword("123"); userDAO.updateByPrimaryKeySelective(user,example); 相當(dāng)于：update user set password='123' where username='joe'

int updateByExample(@Param("record") Account record, @Param("example") AccountExample example);

int updateByPrimaryKeySelective(Account record);//下面是一個(gè)完整的案例 User user = new User();user.setId(101);user.setPassword("joe");userDAO.updateByPrimaryKeySelective(user);

update user set password='joe' where id=101

int updateByPrimaryKeySelective(Account record); //下面是一個(gè)完整的案例  User user = new User();user.setId(101);user.setPassword("joe");userDAO.updateByPrimaryKeySelective(user);

int updateByPrimaryKey(Account record);//下面是一個(gè)完整的案例User user =new User(); user.setId(101); user.setUsername("joe"); user.setPassword("joe"); user.setEmail("joe@163.com"); userDAO.updateByPrimaryKey(user);

update user set username='joe',password='joe',email='joe@163.com' where id=101

int updateByPrimaryKey(Account record); //下面是一個(gè)完整的案例User user =new User(); user.setId(101); user.setUsername("joe"); user.setPassword("joe"); user.setEmail("joe@163.com"); userDAO.updateByPrimaryKey(user);

update user set username='joe',password='joe',email='joe@163.com' where id=101

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">     <property name="dataSource" ref="dataSource" />    <property name="configLocation" value="classpath:configuration.xml"></property>     <property name="mapperLocations" value="classpath:com/xxx/mybatis/mapper/*.xml"/>     <property name="typeAliasesPackage" value="com.tiantian.mybatis.model" />   </bean>  

if (!isEmpty(this.mapperLocations)) {    for (Resource mapperLocation : this.mapperLocations) {     if (mapperLocation == null) {      continue;     }      try {      XMLMapperBuilder xmlMapperBuilder = new XMLMapperBuilder(mapperLocation.getInputStream(),        configuration, mapperLocation.toString(), configuration.getSqlFragments());      xmlMapperBuilder.parse();     } catch (Exception e) {      throw new NestedIOException("Failed to parse mapping resource: '" + mapperLocation + "'", e);     } finally {      ErrorContext.instance().reset();     }      if (logger.isDebugEnabled()) {      logger.debug("Parsed mapper file: '" + mapperLocation + "'");     }    }   } 

public XMLMapperBuilder(Reader reader, Configuration configuration, String resource, Map<String, XNode> sqlFragments) {   this(new XPathParser(reader, true, configuration.getVariables(), new XMLMapperEntityResolver()),     configuration, resource, sqlFragments);  } private XMLMapperBuilder(XPathParser parser, Configuration configuration, String resource, Map<String, XNode> sqlFragments) {   super(configuration);   this.builderAssistant = new MapperBuilderAssistant(configuration, resource);   this.parser = parser;   this.sqlFragments = sqlFragments;   this.resource = resource;  } 

public void parse() {   //如果configuration對(duì)象還沒加載xml配置文件（避免重復(fù)加載，實(shí)際上是確認(rèn)是否解析了mapper節(jié)點(diǎn)的屬性及內(nèi)容，   //為解析它的子節(jié)點(diǎn)如cache、sql、select、resultMap、parameterMap等做準(zhǔn)備），   //則從輸入流中解析mapper節(jié)點(diǎn)，然后再將resource的狀態(tài)置為已加載   if (!configuration.isResourceLoaded(resource)) {    configurationElement(parser.evalNode("/mapper"));    configuration.addLoadedResource(resource);    bindMapperForNamespace();   }   //解析在configurationElement函數(shù)中處理resultMap時(shí)其extends屬性指向的父對(duì)象還沒被處理的<resultMap>節(jié)點(diǎn)   parsePendingResultMaps();   //解析在configurationElement函數(shù)中處理cache-ref時(shí)其指向的對(duì)象不存在的<cache>節(jié)點(diǎn)(如果cache-ref先于其指向的cache節(jié)點(diǎn)加載就會(huì)出現(xiàn)這種情況)   parsePendingChacheRefs();   //同上，如果cache沒加載的話處理statement時(shí)也會(huì)拋出異常   parsePendingStatements();  } 

private void configurationElement(XNode context) {   try {    //獲取mapper節(jié)點(diǎn)的namespace屬性    String namespace = context.getStringAttribute("namespace");    if (namespace.equals("")) {     throw new BuilderException("Mapper's namespace cannot be empty");    }    //設(shè)置當(dāng)前namespace    builderAssistant.setCurrentNamespace(namespace);    //解析mapper的<cache-ref>節(jié)點(diǎn)    cacheRefElement(context.evalNode("cache-ref"));    //解析mapper的<cache>節(jié)點(diǎn)    cacheElement(context.evalNode("cache"));    //解析mapper的<parameterMap>節(jié)點(diǎn)    parameterMapElement(context.evalNodes("/mapper/parameterMap"));    //解析mapper的<resultMap>節(jié)點(diǎn)    resultMapElements(context.evalNodes("/mapper/resultMap"));    //解析mapper的<sql>節(jié)點(diǎn)    sqlElement(context.evalNodes("/mapper/sql"));    //使用XMLStatementBuilder的對(duì)象解析mapper的<select>、<insert>、<update>、<delete>節(jié)點(diǎn),    //mybaits會(huì)使用MappedStatement.Builder類build一個(gè)MappedStatement對(duì)象,    //所以mybaits中一個(gè)sql對(duì)應(yīng)一個(gè)MappedStatement    buildStatementFromContext(context.evalNodes("select|insert|update|delete"));   } catch (Exception e) {    throw new BuilderException("Error parsing Mapper XML. Cause: " + e, e);   }  } 

public void parseStatementNode() {   //ID屬性   String id = context.getStringAttribute("id");   //databaseId屬性   String databaseId = context.getStringAttribute("databaseId");    if (!databaseIdMatchesCurrent(id, databaseId, this.requiredDatabaseId)) {    return;   }   //fetchSize屬性   Integer fetchSize = context.getIntAttribute("fetchSize");   //timeout屬性   Integer timeout = context.getIntAttribute("timeout");   //parameterMap屬性   String parameterMap = context.getStringAttribute("parameterMap");   //parameterType屬性   String parameterType = context.getStringAttribute("parameterType");   Class<?> parameterTypeClass = resolveClass(parameterType);   //resultMap屬性   String resultMap = context.getStringAttribute("resultMap");   //resultType屬性   String resultType = context.getStringAttribute("resultType");   //lang屬性   String lang = context.getStringAttribute("lang");   LanguageDriver langDriver = getLanguageDriver(lang);    Class<?> resultTypeClass = resolveClass(resultType);   //resultSetType屬性   String resultSetType = context.getStringAttribute("resultSetType");   StatementType statementType = StatementType.valueOf(context.getStringAttribute("statementType", StatementType.PREPARED.toString()));   ResultSetType resultSetTypeEnum = resolveResultSetType(resultSetType);    String nodeName = context.getNode().getNodeName();   SqlCommandType sqlCommandType = SqlCommandType.valueOf(nodeName.toUpperCase(Locale.ENGLISH));   //是否是<select>節(jié)點(diǎn)   boolean isSelect = sqlCommandType == SqlCommandType.SELECT;   //flushCache屬性   boolean flushCache = context.getBooleanAttribute("flushCache", !isSelect);   //useCache屬性   boolean useCache = context.getBooleanAttribute("useCache", isSelect);   //resultOrdered屬性   boolean resultOrdered = context.getBooleanAttribute("resultOrdered", false);    // Include Fragments before parsing   XMLIncludeTransformer includeParser = new XMLIncludeTransformer(configuration, builderAssistant);   includeParser.applyIncludes(context.getNode());    // Parse selectKey after includes and remove them.   processSelectKeyNodes(id, parameterTypeClass, langDriver);      // Parse the SQL (pre: <selectKey> and <include> were parsed and removed)   SqlSource sqlSource = langDriver.createSqlSource(configuration, context, parameterTypeClass);   //resultSets屬性   String resultSets = context.getStringAttribute("resultSets");   //keyProperty屬性   String keyProperty = context.getStringAttribute("keyProperty");   //keyColumn屬性   String keyColumn = context.getStringAttribute("keyColumn");   KeyGenerator keyGenerator;   String keyStatementId = id + SelectKeyGenerator.SELECT_KEY_SUFFIX;   keyStatementId = builderAssistant.applyCurrentNamespace(keyStatementId, true);   if (configuration.hasKeyGenerator(keyStatementId)) {    keyGenerator = configuration.getKeyGenerator(keyStatementId);   } else {    //useGeneratedKeys屬性    keyGenerator = context.getBooleanAttribute("useGeneratedKeys",      configuration.isUseGeneratedKeys() && SqlCommandType.INSERT.equals(sqlCommandType))      ? new Jdbc3KeyGenerator() : new NoKeyGenerator();   }    builderAssistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType,     fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass,     resultSetTypeEnum, flushCache, useCache, resultOrdered,      keyGenerator, keyProperty, keyColumn, databaseId, langDriver, resultSets);  }