动态生成带@ 和返回值的mapper方法

好的，下面是一个示例的完整代码：

@Repository
public class DynamicMapperCreator {

  private final SqlSessionFactory sqlSessionFactory;

  @Autowired
  public DynamicMapperCreator(SqlSessionFactory sqlSessionFactory) {
    this.sqlSessionFactory = sqlSessionFactory;
  }

  public <T> void createSelectMethod(Class<T> type, String columnName) throws Exception {
    SqlSession sqlSession = sqlSessionFactory.openSession();
    try {
      Configuration configuration = sqlSession.getConfiguration();
      // 创建动态 MapperBuilderAssistant
      MapperBuilderAssistant assistant = new MapperBuilderAssistant(configuration, "");
      // 构建 @Select 注解
      SelectProviderAnnotationBuilder annotationBuilder =
          new SelectProviderAnnotationBuilder(assistant, type);
      // 生成 Mapper 方法名
      String methodName = "selectBy" + StringUtils.capitalize(columnName);
      // 创建 Mapper 方法
      Method method = type.getDeclaredMethod(methodName, String.class);
      // 生成 Mapper 接口
      Class<?> mapperInterface = createMapperInterface(type, methodName, method.getReturnType());
      // 注册 Mapper 接口
      configuration.addMapper(mapperInterface);
      // 输出 Mapper 接口代码
      System.out.println("Dynamic Mapper Interface: ");
      System.out.println(ReflectUtils.getFullClassName(mapperInterface));
      System.out.println(ReflectUtils.getCode(mapperInterface));
    } finally {
      sqlSession.close();
    }
  }

  /**
   * 动态创建 Mapper 接口
   *
   * @param type 实体类类型
   * @param methodName 方法名
   * @param returnType 返回值类型
   * @return Mapper 接口类型
   */
  private <T> Class<?> createMapperInterface(Class<T> type, String methodName,
      Class<?> returnType) {
    MapperBuilder mapperBuilder = new MapperBuilder(type);
    return mapperBuilder.addStatement(
            "org.apache.ibatis.annotations.SelectProvider(type = "
                + SelectProviderAnnotationBuilder.class.getName()
                + ".class, method = \"buildSql\")")
        .addMethod(
            new MethodBuilder(returnType, methodName)
                .addParameter(String.class, "value")
                .toMethod())
        .toMapper();
  }
}

class MapperBuilder {

  private final Class<?> type;
  private final List<String> methods = new ArrayList<>();

  public MapperBuilder(Class<?> type) {
    this.type = type;
  }

  public MapperBuilder addStatement(String statement) {
    methods.add(statement);
    return this;
  }

  public MapperBuilder addMethod(Method method) {
    methods.add(method.toString());
    return this;
  }

  public Class<?> toMapper() {
    StringBuilder sb = new StringBuilder();
    sb.append("package ").append(type.getPackage().getName()).append(";\n\n");
    sb.append("public interface ").append(type.getSimpleName()).append("Mapper {\n\n");
    for (String method : methods) {
      sb.append("  ").append(method).append(";\n\n");
    }
    sb.append("}\n");
    return ReflectUtils.compile(type.getSimpleName() + "Mapper", sb.toString());
  }
}

class MethodBuilder {

  private final Class<?> returnType;
  private final String methodName;
  private final List<String> parameters = new ArrayList<>();

  public MethodBuilder(Class<?> returnType, String methodName) {
    this.returnType = returnType;
    this.methodName = methodName;
  }

  public MethodBuilder addParameter(Class<?> type, String name) {
    parameters.add(type.getSimpleName() + " " + name);
    return this;
  }

  public Method toMethod() {
    StringBuilder sb = new StringBuilder();
    sb.append("@SuppressWarnings(\"all\")\n");
    sb.append("public ").append(ReflectUtils.getTypeName(returnType