org.apache.ibatis.mapping.ResultSetType Java Examples

protected void addMappedStatement(String id, SqlSource sqlSource,
		StatementType statementType, SqlCommandType sqlCommandType, Integer fetchSize,
		Integer timeout, String parameterMap, Class<?> parameterType,
		String resultMap, Class<?> resultType, ResultSetType resultSetType,
		boolean flushCache, boolean useCache, boolean resultOrdered,
		KeyGenerator keyGenerator, String keyProperty, String keyColumn,
		String databaseId, LanguageDriver lang, String resultSets) {

	assistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType,
			fetchSize, timeout, parameterMap, parameterType, resultMap, resultType,
			resultSetType, flushCache, useCache, resultOrdered, keyGenerator,
			keyProperty, keyColumn, databaseId, lang, resultSets);

}
 

private KeyGenerator handleSelectKeyAnnotation(SelectKey selectKeyAnnotation, String baseStatementId, Class<?> parameterTypeClass, LanguageDriver languageDriver) {
  String id = baseStatementId + SelectKeyGenerator.SELECT_KEY_SUFFIX;
  Class<?> resultTypeClass = selectKeyAnnotation.resultType();
  StatementType statementType = selectKeyAnnotation.statementType();
  String keyProperty = selectKeyAnnotation.keyProperty();
  String keyColumn = selectKeyAnnotation.keyColumn();
  boolean executeBefore = selectKeyAnnotation.before();

  // defaults
  boolean useCache = false;
  KeyGenerator keyGenerator = new NoKeyGenerator();
  Integer fetchSize = null;
  Integer timeout = null;
  boolean flushCache = false;
  String parameterMap = null;
  String resultMap = null;
  ResultSetType resultSetTypeEnum = null;

  SqlSource sqlSource = buildSqlSourceFromStrings(selectKeyAnnotation.statement(), parameterTypeClass, languageDriver);
  SqlCommandType sqlCommandType = SqlCommandType.SELECT;

  assistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType, fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass, resultSetTypeEnum,
      flushCache, useCache, false,
      keyGenerator, keyProperty, keyColumn, null, languageDriver, null);

  id = assistant.applyCurrentNamespace(id, false);

  MappedStatement keyStatement = configuration.getMappedStatement(id, false);
  SelectKeyGenerator answer = new SelectKeyGenerator(keyStatement, executeBefore);
  configuration.addKeyGenerator(id, answer);
  return answer;
}
 

private void setStatementResultMap(
    String resultMap,
    Class<?> resultType,
    ResultSetType resultSetType,
    MappedStatement.Builder statementBuilder) {
  resultMap = applyCurrentNamespace(resultMap, true);

  List<ResultMap> resultMaps = new ArrayList<ResultMap>();
  if (resultMap != null) {
    //2.1 resultMap是高级功能
    String[] resultMapNames = resultMap.split(",");
    for (String resultMapName : resultMapNames) {
      try {
        resultMaps.add(configuration.getResultMap(resultMapName.trim()));
      } catch (IllegalArgumentException e) {
        throw new IncompleteElementException("Could not find result map " + resultMapName, e);
      }
    }
  } else if (resultType != null) {
    //2.2 resultType,一般用这个足矣了
    //<select id="selectUsers" resultType="User">
    //这种情况下,MyBatis 会在幕后自动创建一个 ResultMap,基于属性名来映射列到 JavaBean 的属性上。
    //如果列名没有精确匹配,你可以在列名上使用 select 字句的别名来匹配标签。
    //创建一个inline result map, 把resultType设上就OK了，
    //然后后面被DefaultResultSetHandler.createResultObject()使用
    //DefaultResultSetHandler.getRowValue()使用
    ResultMap.Builder inlineResultMapBuilder = new ResultMap.Builder(
        configuration,
        statementBuilder.id() + "-Inline",
        resultType,
        new ArrayList<ResultMapping>(),
        null);
    resultMaps.add(inlineResultMapBuilder.build());
  }
  statementBuilder.resultMaps(resultMaps);

  statementBuilder.resultSetType(resultSetType);
}
 

/** Backward compatibility signature */
//向后兼容方法
public MappedStatement addMappedStatement(
  String id,
  SqlSource sqlSource,
  StatementType statementType,
  SqlCommandType sqlCommandType,
  Integer fetchSize,
  Integer timeout,
  String parameterMap,
  Class<?> parameterType,
  String resultMap,
  Class<?> resultType,
  ResultSetType resultSetType,
  boolean flushCache,
  boolean useCache,
  boolean resultOrdered,
  KeyGenerator keyGenerator,
  String keyProperty,
  String keyColumn,
  String databaseId,
  LanguageDriver lang) {
  return addMappedStatement(
    id, sqlSource, statementType, sqlCommandType, fetchSize, timeout, 
    parameterMap, parameterType, resultMap, resultType, resultSetType, 
    flushCache, useCache, resultOrdered, keyGenerator, keyProperty, 
    keyColumn, databaseId, lang, null);
}
 

private void parseSelectKeyNode(String id, XNode nodeToHandle, Class<?> parameterTypeClass, LanguageDriver langDriver, String databaseId) {
  String resultType = nodeToHandle.getStringAttribute("resultType");
  Class<?> resultTypeClass = resolveClass(resultType);
  StatementType statementType = StatementType.valueOf(nodeToHandle.getStringAttribute("statementType", StatementType.PREPARED.toString()));
  String keyProperty = nodeToHandle.getStringAttribute("keyProperty");
  String keyColumn = nodeToHandle.getStringAttribute("keyColumn");
  boolean executeBefore = "BEFORE".equals(nodeToHandle.getStringAttribute("order", "AFTER"));

  //defaults
  boolean useCache = false;
  boolean resultOrdered = false;
  KeyGenerator keyGenerator = new NoKeyGenerator();
  Integer fetchSize = null;
  Integer timeout = null;
  boolean flushCache = false;
  String parameterMap = null;
  String resultMap = null;
  ResultSetType resultSetTypeEnum = null;

  SqlSource sqlSource = langDriver.createSqlSource(configuration, nodeToHandle, parameterTypeClass);
  SqlCommandType sqlCommandType = SqlCommandType.SELECT;

  builderAssistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType,
      fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass,
      resultSetTypeEnum, flushCache, useCache, resultOrdered,
      keyGenerator, keyProperty, keyColumn, databaseId, langDriver, null);

  id = builderAssistant.applyCurrentNamespace(id, false);

  MappedStatement keyStatement = configuration.getMappedStatement(id, false);
  configuration.addKeyGenerator(id, new SelectKeyGenerator(keyStatement, executeBefore));
}
 

protected ResultSetType resolveResultSetType(String alias) {
  if (alias == null) {
    return null;
  }
  try {
    return ResultSetType.valueOf(alias);
  } catch (IllegalArgumentException e) {
    throw new BuilderException("Error resolving ResultSetType. Cause: " + e, e);
  }
}
 

private KeyGenerator handleSelectKeyAnnotation(SelectKey selectKeyAnnotation, String baseStatementId, Class<?> parameterTypeClass, LanguageDriver languageDriver) {
  String id = baseStatementId + SelectKeyGenerator.SELECT_KEY_SUFFIX;
  Class<?> resultTypeClass = selectKeyAnnotation.resultType();
  StatementType statementType = selectKeyAnnotation.statementType();
  String keyProperty = selectKeyAnnotation.keyProperty();
  String keyColumn = selectKeyAnnotation.keyColumn();
  boolean executeBefore = selectKeyAnnotation.before();

  // defaults
  boolean useCache = false;
  KeyGenerator keyGenerator = new NoKeyGenerator();
  Integer fetchSize = null;
  Integer timeout = null;
  boolean flushCache = false;
  String parameterMap = null;
  String resultMap = null;
  ResultSetType resultSetTypeEnum = null;

  SqlSource sqlSource = buildSqlSourceFromStrings(selectKeyAnnotation.statement(), parameterTypeClass, languageDriver);
  SqlCommandType sqlCommandType = SqlCommandType.SELECT;

  assistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType, fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass, resultSetTypeEnum,
      flushCache, useCache, false,
      keyGenerator, keyProperty, keyColumn, null, languageDriver, null);

  id = assistant.applyCurrentNamespace(id, false);

  MappedStatement keyStatement = configuration.getMappedStatement(id, false);
  SelectKeyGenerator answer = new SelectKeyGenerator(keyStatement, executeBefore);
  configuration.addKeyGenerator(id, answer);
  return answer;
}
 

private void setStatementResultMap(
    String resultMap,
    Class<?> resultType,
    ResultSetType resultSetType,
    MappedStatement.Builder statementBuilder) {
  resultMap = applyCurrentNamespace(resultMap, true);

  List<ResultMap> resultMaps = new ArrayList<ResultMap>();
  if (resultMap != null) {
    //2.1 resultMap是高级功能
    String[] resultMapNames = resultMap.split(",");
    for (String resultMapName : resultMapNames) {
      try {
        resultMaps.add(configuration.getResultMap(resultMapName.trim()));
      } catch (IllegalArgumentException e) {
        throw new IncompleteElementException("Could not find result map " + resultMapName, e);
      }
    }
  } else if (resultType != null) {
    //2.2 resultType,一般用这个足矣了
    //<select id="selectUsers" resultType="User">
    //这种情况下,MyBatis 会在幕后自动创建一个 ResultMap,基于属性名来映射列到 JavaBean 的属性上。
    //如果列名没有精确匹配,你可以在列名上使用 select 字句的别名来匹配标签。
    //创建一个inline result map, 把resultType设上就OK了，
    //然后后面被DefaultResultSetHandler.createResultObject()使用
    //DefaultResultSetHandler.getRowValue()使用
    ResultMap.Builder inlineResultMapBuilder = new ResultMap.Builder(
        configuration,
        statementBuilder.id() + "-Inline",
        resultType,
        new ArrayList<ResultMapping>(),
        null);
    resultMaps.add(inlineResultMapBuilder.build());
  }
  statementBuilder.resultMaps(resultMaps);

  statementBuilder.resultSetType(resultSetType);
}
 

/** Backward compatibility signature */
//向后兼容方法
public MappedStatement addMappedStatement(
  String id,
  SqlSource sqlSource,
  StatementType statementType,
  SqlCommandType sqlCommandType,
  Integer fetchSize,
  Integer timeout,
  String parameterMap,
  Class<?> parameterType,
  String resultMap,
  Class<?> resultType,
  ResultSetType resultSetType,
  boolean flushCache,
  boolean useCache,
  boolean resultOrdered,
  KeyGenerator keyGenerator,
  String keyProperty,
  String keyColumn,
  String databaseId,
  LanguageDriver lang) {
  return addMappedStatement(
    id, sqlSource, statementType, sqlCommandType, fetchSize, timeout, 
    parameterMap, parameterType, resultMap, resultType, resultSetType, 
    flushCache, useCache, resultOrdered, keyGenerator, keyProperty, 
    keyColumn, databaseId, lang, null);
}
 

private void parseSelectKeyNode(String id, XNode nodeToHandle, Class<?> parameterTypeClass, LanguageDriver langDriver, String databaseId) {
  String resultType = nodeToHandle.getStringAttribute("resultType");
  Class<?> resultTypeClass = resolveClass(resultType);
  StatementType statementType = StatementType.valueOf(nodeToHandle.getStringAttribute("statementType", StatementType.PREPARED.toString()));
  String keyProperty = nodeToHandle.getStringAttribute("keyProperty");
  String keyColumn = nodeToHandle.getStringAttribute("keyColumn");
  boolean executeBefore = "BEFORE".equals(nodeToHandle.getStringAttribute("order", "AFTER"));

  //defaults
  boolean useCache = false;
  boolean resultOrdered = false;
  KeyGenerator keyGenerator = new NoKeyGenerator();
  Integer fetchSize = null;
  Integer timeout = null;
  boolean flushCache = false;
  String parameterMap = null;
  String resultMap = null;
  ResultSetType resultSetTypeEnum = null;

  SqlSource sqlSource = langDriver.createSqlSource(configuration, nodeToHandle, parameterTypeClass);
  SqlCommandType sqlCommandType = SqlCommandType.SELECT;

  builderAssistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType,
      fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass,
      resultSetTypeEnum, flushCache, useCache, resultOrdered,
      keyGenerator, keyProperty, keyColumn, databaseId, langDriver, null);

  id = builderAssistant.applyCurrentNamespace(id, false);

  MappedStatement keyStatement = configuration.getMappedStatement(id, false);
  configuration.addKeyGenerator(id, new SelectKeyGenerator(keyStatement, executeBefore));
}
 

protected ResultSetType resolveResultSetType(String alias) {
  if (alias == null) {
    return null;
  }
  try {
    return ResultSetType.valueOf(alias);
  } catch (IllegalArgumentException e) {
    throw new BuilderException("Error resolving ResultSetType. Cause: " + e, e);
  }
}
 

public MappedStatement addMappedStatement(
    String id,
    SqlSource sqlSource,
    StatementType statementType,
    SqlCommandType sqlCommandType,
    Integer fetchSize,
    Integer timeout,
    String parameterMap,
    Class<?> parameterType,
    String resultMap,
    Class<?> resultType,
    ResultSetType resultSetType,
    boolean flushCache,
    boolean useCache,
    boolean resultOrdered,
    KeyGenerator keyGenerator,
    String keyProperty,
    String keyColumn,
    String databaseId,
    LanguageDriver lang,
    String resultSets) {
  
  if (unresolvedCacheRef) {
    throw new IncompleteElementException("Cache-ref not yet resolved");
  }
  
  //为id加上namespace前缀
  id = applyCurrentNamespace(id, false);
  //是否是select语句
  boolean isSelect = sqlCommandType == SqlCommandType.SELECT;

  //又是建造者模式
  MappedStatement.Builder statementBuilder = new MappedStatement.Builder(configuration, id, sqlSource, sqlCommandType);
  statementBuilder.resource(resource);
  statementBuilder.fetchSize(fetchSize);
  statementBuilder.statementType(statementType);
  statementBuilder.keyGenerator(keyGenerator);
  statementBuilder.keyProperty(keyProperty);
  statementBuilder.keyColumn(keyColumn);
  statementBuilder.databaseId(databaseId);
  statementBuilder.lang(lang);
  statementBuilder.resultOrdered(resultOrdered);
  statementBuilder.resulSets(resultSets);
  setStatementTimeout(timeout, statementBuilder);

  //1.参数映射
  setStatementParameterMap(parameterMap, parameterType, statementBuilder);
  //2.结果映射
  setStatementResultMap(resultMap, resultType, resultSetType, statementBuilder);
  setStatementCache(isSelect, flushCache, useCache, currentCache, statementBuilder);

  MappedStatement statement = statementBuilder.build();
  //建造好调用configuration.addMappedStatement
  configuration.addMappedStatement(statement);
  return statement;
}
 

public void parseStatementNode() {
   String id = context.getStringAttribute("id");
   String databaseId = context.getStringAttribute("databaseId");

   //如果databaseId不匹配，退出
   if (!databaseIdMatchesCurrent(id, databaseId, this.requiredDatabaseId)) {
     return;
   }

   //暗示驱动程序每次批量返回的结果行数
   Integer fetchSize = context.getIntAttribute("fetchSize");
   //超时时间
   Integer timeout = context.getIntAttribute("timeout");
   //引用外部 parameterMap,已废弃
   String parameterMap = context.getStringAttribute("parameterMap");
   //参数类型
   String parameterType = context.getStringAttribute("parameterType");
   Class<?> parameterTypeClass = resolveClass(parameterType);
   //引用外部的 resultMap(高级功能)
   String resultMap = context.getStringAttribute("resultMap");
   //结果类型
   String resultType = context.getStringAttribute("resultType");
   //脚本语言,mybatis3.2的新功能
   String lang = context.getStringAttribute("lang");
   //得到语言驱动
   LanguageDriver langDriver = getLanguageDriver(lang);

   Class<?> resultTypeClass = resolveClass(resultType);
   //结果集类型，FORWARD_ONLY|SCROLL_SENSITIVE|SCROLL_INSENSITIVE 中的一种
   String resultSetType = context.getStringAttribute("resultSetType");
   //语句类型, STATEMENT|PREPARED|CALLABLE 的一种
   StatementType statementType = StatementType.valueOf(context.getStringAttribute("statementType", StatementType.PREPARED.toString()));
   ResultSetType resultSetTypeEnum = resolveResultSetType(resultSetType);

   //获取命令类型(select|insert|update|delete)
   String nodeName = context.getNode().getNodeName();
   SqlCommandType sqlCommandType = SqlCommandType.valueOf(nodeName.toUpperCase(Locale.ENGLISH));
   boolean isSelect = sqlCommandType == SqlCommandType.SELECT;
   boolean flushCache = context.getBooleanAttribute("flushCache", !isSelect);
   //是否要缓存select结果
   boolean useCache = context.getBooleanAttribute("useCache", isSelect);
   //仅针对嵌套结果 select 语句适用：如果为 true，就是假设包含了嵌套结果集或是分组了，这样的话当返回一个主结果行的时候，就不会发生有对前面结果集的引用的情况。
   //这就使得在获取嵌套的结果集的时候不至于导致内存不够用。默认值：false。 
   boolean resultOrdered = context.getBooleanAttribute("resultOrdered", false);

   // Include Fragments before parsing
   //解析之前先解析<include>SQL片段
   XMLIncludeTransformer includeParser = new XMLIncludeTransformer(configuration, builderAssistant);
   includeParser.applyIncludes(context.getNode());

   // Parse selectKey after includes and remove them.
   //解析之前先解析<selectKey>
   processSelectKeyNodes(id, parameterTypeClass, langDriver);
   
   // Parse the SQL (pre: <selectKey> and <include> were parsed and removed)
   //解析成SqlSource，一般是DynamicSqlSource
   SqlSource sqlSource = langDriver.createSqlSource(configuration, context, parameterTypeClass);
   String resultSets = context.getStringAttribute("resultSets");
   //(仅对 insert 有用) 标记一个属性, MyBatis 会通过 getGeneratedKeys 或者通过 insert 语句的 selectKey 子元素设置它的值
   String keyProperty = context.getStringAttribute("keyProperty");
   //(仅对 insert 有用) 标记一个属性, MyBatis 会通过 getGeneratedKeys 或者通过 insert 语句的 selectKey 子元素设置它的值
   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 {
     keyGenerator = context.getBooleanAttribute("useGeneratedKeys",
         configuration.isUseGeneratedKeys() && SqlCommandType.INSERT.equals(sqlCommandType))
         ? new Jdbc3KeyGenerator() : new NoKeyGenerator();
   }

//又去调助手类
   builderAssistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType,
       fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass,
       resultSetTypeEnum, flushCache, useCache, resultOrdered, 
       keyGenerator, keyProperty, keyColumn, databaseId, langDriver, resultSets);
 }
 

public MappedStatement addMappedStatement(
    String id,
    SqlSource sqlSource,
    StatementType statementType,
    SqlCommandType sqlCommandType,
    Integer fetchSize,
    Integer timeout,
    String parameterMap,
    Class<?> parameterType,
    String resultMap,
    Class<?> resultType,
    ResultSetType resultSetType,
    boolean flushCache,
    boolean useCache,
    boolean resultOrdered,
    KeyGenerator keyGenerator,
    String keyProperty,
    String keyColumn,
    String databaseId,
    LanguageDriver lang,
    String resultSets) {
  
  if (unresolvedCacheRef) {
    throw new IncompleteElementException("Cache-ref not yet resolved");
  }
  
  //为id加上namespace前缀
  id = applyCurrentNamespace(id, false);
  //是否是select语句
  boolean isSelect = sqlCommandType == SqlCommandType.SELECT;

  //又是建造者模式
  MappedStatement.Builder statementBuilder = new MappedStatement.Builder(configuration, id, sqlSource, sqlCommandType);
  statementBuilder.resource(resource);
  statementBuilder.fetchSize(fetchSize);
  statementBuilder.statementType(statementType);
  statementBuilder.keyGenerator(keyGenerator);
  statementBuilder.keyProperty(keyProperty);
  statementBuilder.keyColumn(keyColumn);
  statementBuilder.databaseId(databaseId);
  statementBuilder.lang(lang);
  statementBuilder.resultOrdered(resultOrdered);
  statementBuilder.resulSets(resultSets);
  setStatementTimeout(timeout, statementBuilder);

  //1.参数映射
  setStatementParameterMap(parameterMap, parameterType, statementBuilder);
  //2.结果映射
  setStatementResultMap(resultMap, resultType, resultSetType, statementBuilder);
  setStatementCache(isSelect, flushCache, useCache, currentCache, statementBuilder);

  MappedStatement statement = statementBuilder.build();
  //建造好调用configuration.addMappedStatement
  configuration.addMappedStatement(statement);
  return statement;
}
 

public void parseStatementNode() {
   String id = context.getStringAttribute("id");
   String databaseId = context.getStringAttribute("databaseId");

   //如果databaseId不匹配，退出
   if (!databaseIdMatchesCurrent(id, databaseId, this.requiredDatabaseId)) {
     return;
   }

   //暗示驱动程序每次批量返回的结果行数
   Integer fetchSize = context.getIntAttribute("fetchSize");
   //超时时间
   Integer timeout = context.getIntAttribute("timeout");
   //引用外部 parameterMap,已废弃
   String parameterMap = context.getStringAttribute("parameterMap");
   //参数类型
   String parameterType = context.getStringAttribute("parameterType");
   Class<?> parameterTypeClass = resolveClass(parameterType);
   //引用外部的 resultMap(高级功能)
   String resultMap = context.getStringAttribute("resultMap");
   //结果类型
   String resultType = context.getStringAttribute("resultType");
   //脚本语言,mybatis3.2的新功能
   String lang = context.getStringAttribute("lang");
   //得到语言驱动
   LanguageDriver langDriver = getLanguageDriver(lang);

   Class<?> resultTypeClass = resolveClass(resultType);
   //结果集类型，FORWARD_ONLY|SCROLL_SENSITIVE|SCROLL_INSENSITIVE 中的一种
   String resultSetType = context.getStringAttribute("resultSetType");
   //语句类型, STATEMENT|PREPARED|CALLABLE 的一种
   StatementType statementType = StatementType.valueOf(context.getStringAttribute("statementType", StatementType.PREPARED.toString()));
   ResultSetType resultSetTypeEnum = resolveResultSetType(resultSetType);

   //获取命令类型(select|insert|update|delete)
   String nodeName = context.getNode().getNodeName();
   SqlCommandType sqlCommandType = SqlCommandType.valueOf(nodeName.toUpperCase(Locale.ENGLISH));
   boolean isSelect = sqlCommandType == SqlCommandType.SELECT;
   boolean flushCache = context.getBooleanAttribute("flushCache", !isSelect);
   //是否要缓存select结果
   boolean useCache = context.getBooleanAttribute("useCache", isSelect);
   //仅针对嵌套结果 select 语句适用：如果为 true，就是假设包含了嵌套结果集或是分组了，这样的话当返回一个主结果行的时候，就不会发生有对前面结果集的引用的情况。
   //这就使得在获取嵌套的结果集的时候不至于导致内存不够用。默认值：false。 
   boolean resultOrdered = context.getBooleanAttribute("resultOrdered", false);

   // Include Fragments before parsing
   //解析之前先解析<include>SQL片段
   XMLIncludeTransformer includeParser = new XMLIncludeTransformer(configuration, builderAssistant);
   includeParser.applyIncludes(context.getNode());

   // Parse selectKey after includes and remove them.
   //解析之前先解析<selectKey>
   processSelectKeyNodes(id, parameterTypeClass, langDriver);
   
   // Parse the SQL (pre: <selectKey> and <include> were parsed and removed)
   //解析成SqlSource，一般是DynamicSqlSource
   SqlSource sqlSource = langDriver.createSqlSource(configuration, context, parameterTypeClass);
   String resultSets = context.getStringAttribute("resultSets");
   //(仅对 insert 有用) 标记一个属性, MyBatis 会通过 getGeneratedKeys 或者通过 insert 语句的 selectKey 子元素设置它的值
   String keyProperty = context.getStringAttribute("keyProperty");
   //(仅对 insert 有用) 标记一个属性, MyBatis 会通过 getGeneratedKeys 或者通过 insert 语句的 selectKey 子元素设置它的值
   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 {
     keyGenerator = context.getBooleanAttribute("useGeneratedKeys",
         configuration.isUseGeneratedKeys() && SqlCommandType.INSERT.equals(sqlCommandType))
         ? new Jdbc3KeyGenerator() : new NoKeyGenerator();
   }

//又去调助手类
   builderAssistant.addMappedStatement(id, sqlSource, statementType, sqlCommandType,
       fetchSize, timeout, parameterMap, parameterTypeClass, resultMap, resultTypeClass,
       resultSetTypeEnum, flushCache, useCache, resultOrdered, 
       keyGenerator, keyProperty, keyColumn, databaseId, langDriver, resultSets);
 }