mark mybatis annotation driven

mybatis annotaion方式并不像spring，需要指定annotation-driven来启用annotaion特性。

mybatis默认支持annotation，参考MapperRegistry#addMapper

/**
* MapperRegistry Configuration实现annotaion mapper注册的帮助类
**/
public <T> void addMapper(Class<T> type) {
if (type.isInterface()) {
try {
MapperAnnotationBuilder parser = new MapperAnnotationBuilder(config, type);
parser.parse();
} finally {
//...
}
}
}

接下来就是对Method对象的parse，解析出完整的mapped-statement 配置

public void parse() {
// Class级别解析
parseCache();
parseCacheRef();
Method[] methods = type.getMethods();
// Method级别解析
for (Method method : methods) {
try {
// 根据Annotation解析完整的MappedStatement信息
parseStatement(method);
} catch (IncompleteElementException e) {
// 加入待处理队列
configuration.addIncompleteMethod(new MethodResolver(this, method));
}
}
// 再次尝试解析 IncompleteMethod
parsePendingMethods();
}

最后，将解析完的mapped-statement 归入configuration

MappedStatement.Builder statementBuilder = new MappedStatement.Builder(configuration, id, sqlSource, sqlCommandType);
// ......
MappedStatement statement = statementBuilder.build();
configuration.addMappedStatement(statement);

附：mybatis Mapper XML 解析顺序

循环指定的mapperLocations，创建对应XMLMapperBuilder

解析mapper node，addMappedStatement

guess xml namespace(Class)，引入Annotation处理流程

创建MapperAnnotationBuilder

解析 Class.method annotation，addMappedStatement

……