副本列表<;A>;要列出的项目<;B>;使用Java流API的项目
我正在尝试将列表元素从副本列表<;A>;要列出的项目<;B>;使用Java流API的项目,java,collections,java-8,Java,Collections,Java 8,我正在尝试将列表元素从列表复制到列表,并遇到一些类型错误 我的代码: List<AttachmentTypeDto> attachmentTypeList=clientDetails.getAttachmentTypeDto(); List<ClientAttachmentTypeEntity> mappedAttachmentList=attachmentTypeList.stream().map(temp ->{ ClientAttac
列表
复制到列表
,并遇到一些类型错误
我的代码:
List<AttachmentTypeDto> attachmentTypeList=clientDetails.getAttachmentTypeDto();
List<ClientAttachmentTypeEntity> mappedAttachmentList=attachmentTypeList.stream().map(temp ->{
ClientAttachmentTypeEntity toAttachmentObject=new ClientAttachmentTypeEntity();
toAttachmentObject.setAttachmentTypeId(temp.getAttachmentTypeId());
toAttachmentObject.setClientId(temp.getClientId());
}).collect(Collectors.toList());
List attachmentTypeList=clientDetails.getAttachmentTypeDto();
List mappedAttachmentList=attachmentTypeList.stream().map(临时->{
ClientAttachmentTypeEntity to AttachmentObject=新ClientAttachmentTypeEntity();
toAttachmentObject.setAttachmentTypeId(temp.getAttachmentTypeId());
toAttachmentObject.setClientId(temp.getClientId());
}).collect(Collectors.toList());
它给了我这样的错误:
The method map(Function<? super AttachmentTypeDto,? extends R>) in the type Stream<AttachmentTypeDto> is not applicable for the arguments ((<no type> temp) -> {})
方法映射(函数我不明白为什么有人投票-1你应该在映射函数中返回toAttachmentObject
。.map(temp->{…return toAttachmentObject;}).
这确实解决了我的问题,谢谢@Hadi JA备注:我建议提取映射过程(即.map中的lambda体)(…)
在单独的方法中,例如,convertAttachmentDtoToClientAttachmentDto(…)
然后调用map(this::convertAttachmentDtoToClientAttachmentDto)
。太好了,我正在研究相同的解决方案:)我不明白为什么有人投票-1你应该在map函数中返回toAttachmentObject
。.map>(temp->{…return to attachmentobject;}).
这真的解决了我的问题,谢谢@Hadi JA备注:我建议用单独的方法提取映射过程(即.map(…)
中的lambda体,例如convertAttachmentDtoToClientAttachmentDto(…)
然后调用映射(this::convertAttachmentDtoToClientAttachmentDto)
。太好了,我正在使用相同的解决方案:)