深入探索MyBatis的动态代理模式

public class MyBatisMapperProxy<T> implements InvocationHandler {
    private final SqlSession sqlSession;
    private final Class<T> mapperInterface;
    private final Map<Method, MapperMethod> methodCache;

    public MyBatisMapperProxy(SqlSession sqlSession, Class<T> mapperInterface, Map<Method, MapperMethod> methodCache) {
        this.sqlSession = sqlSession;
        this.mapperInterface = mapperInterface;
        this.methodCache = methodCache;
    }

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        if (Object.class.equals(method.getDeclaringClass())) {
            try {
                // 处理 Object 中定义的方法，例如 hashCode(), equals() 等
                return method.invoke(this, args);
            } catch (Throwable t) {
                throw ExceptionUtil.unwrapThrowable(t);
            }
        }
        // 使用 MapperMethod 来执行具体的数据库操作
        final MapperMethod mapperMethod = cachedMapperMethod(method);
        return mapperMethod.execute(sqlSession, args);
    }

    private MapperMethod cachedMapperMethod(Method method) {
        MapperMethod mapperMethod = methodCache.get(method);
        if (mapperMethod == null) {
            mapperMethod = new MapperMethod(mapperInterface, method);
            methodCache.put(method, mapperMethod);
        }
        return mapperMethod;
    }
}