场景:
应用MyBatis Plus 和通用Mapper
继承自ServiceImpl实现对Service里的方法进行包装再处理。
public interface IServiceBase2<T extends AbstractDTO> {
}
public class ServiceBaseImpl2<M extends BaseMapper<P>,P extends Model<P>,D extends AbstractDTO> extends ServiceImpl<M,P>  implements IServiceBase2<D> {
    private Class<P> poClazz;
    private Class<D> dtoClazz;
    public ServiceBaseImpl2(){
        Type superClass = getClass().getGenericSuperclass();
        if (superClass instanceof ParameterizedType) {
            ParameterizedType parameterizedType = (ParameterizedType) superClass;
            Type[] types = parameterizedType.getActualTypeArguments();
            if (types != null && types.length == 3) {
                if (types[1] instanceof Class) {
                    poClazz = (Class<P>) types[1];
                }
                if (types[2] instanceof Class) {
                    dtoClazz = (Class<D>) types[2];
                }
            }
        }
    }
    @Override
    public D selectByIdDTO(Serializable var1) throws ClassNotFoundException, IllegalAccessException, InstantiationException, NoSuchMethodException, InvocationTargetException {
        P p = super.selectById(var1);
        String classPath = poClazz.getName() + "POJOMapperImpl";// "com.api.modular.clinicalcase.dto.mapper.ClinicalcasePOJOMapperImpl";
        classPath = classPath.replace("model","dto.mapper");
        Class mapperClazz = Class.forName(classPath);
        Object newInstance = mapperClazz.newInstance();
        Method[] methods = mapperClazz.getMethods();
        Method method = mapperClazz.getMethod("doToDto", poClazz);
        D result = (D) method.invoke(newInstance, p);
        return result;
    }
}
错误:
启动项目报错:No qualifying bean of type 'com.baomidou.mybatisplus.mapper.BaseMapper<?>' available: expected single matching bean but found 4
解决:
将ServiceBaseImpl 更改为抽象类
public abstract class ServiceBaseImpl2<M extends BaseMapper<P>,P extends Model<P>,D extends AbstractDTO> extends ServiceImpl<M,P>  implements IServiceBase2<D> {
}
来源:https://www.cnblogs.com/icebutterfly/p/9851853.html