我正在使用 spring 数据 (mongoDb),并且我有我的存储库:
public interface StoriesRepository extends PagingAndSortingRepository<Story, String> {}
然后我有一个 Controller :
@RequestMapping(method = RequestMethod.GET)
public ResponseEntity<Page<StoryResponse>> getStories(Pageable pageable) {
Page<StoryResponse> stories = storiesRepository.findAll(pageable).map(StoryResponseMapper::toStoryResponse);
return ResponseEntity.ok(stories);
}
一切正常,但我无法使用 RestTemplate getForEntity 方法使用我的端点:
def entity = restTemplate.getForEntity(getLocalhost("/story"), new TypeReference<Page<StoryResponse>>(){}.class)
我应该提供什么类来成功反序列化我的实体页面?
最佳答案
new TypeReference<Page<StoryResponse>>() {}
此语句的问题在于 Jackson 无法实例化抽象类型。您应该向 Jackson 提供有关如何使用具体类型实例化 Page
的信息。但它的具体类型 PageImpl
没有默认构造函数或任何 @JsonCreator
,因此您也可以不使用以下代码:
new TypeReference<PageImpl<StoryResponse>>() {}
由于您无法将所需的信息添加到 Page
类中,因此最好为 Page
接口(interface)创建一个自定义实现,该接口(interface)具有默认的无参数构造函数,就像这个 answer .然后在类型引用中使用该自定义实现,如下所示:
new TypeReference<CustomPageImpl<StoryResponse>>() {}
这是从链接问题复制的自定义实现:
public class CustomPageImpl<T> extends PageImpl<T> {
private static final long serialVersionUID = 1L;
private int number;
private int size;
private int totalPages;
private int numberOfElements;
private long totalElements;
private boolean previousPage;
private boolean firstPage;
private boolean nextPage;
private boolean lastPage;
private List<T> content;
private Sort sort;
public CustomPageImpl() {
super(new ArrayList<>());
}
@Override
public int getNumber() {
return number;
}
public void setNumber(int number) {
this.number = number;
}
@Override
public int getSize() {
return size;
}
public void setSize(int size) {
this.size = size;
}
@Override
public int getTotalPages() {
return totalPages;
}
public void setTotalPages(int totalPages) {
this.totalPages = totalPages;
}
@Override
public int getNumberOfElements() {
return numberOfElements;
}
public void setNumberOfElements(int numberOfElements) {
this.numberOfElements = numberOfElements;
}
@Override
public long getTotalElements() {
return totalElements;
}
public void setTotalElements(long totalElements) {
this.totalElements = totalElements;
}
public boolean isPreviousPage() {
return previousPage;
}
public void setPreviousPage(boolean previousPage) {
this.previousPage = previousPage;
}
public boolean isFirstPage() {
return firstPage;
}
public void setFirstPage(boolean firstPage) {
this.firstPage = firstPage;
}
public boolean isNextPage() {
return nextPage;
}
public void setNextPage(boolean nextPage) {
this.nextPage = nextPage;
}
public boolean isLastPage() {
return lastPage;
}
public void setLastPage(boolean lastPage) {
this.lastPage = lastPage;
}
@Override
public List<T> getContent() {
return content;
}
public void setContent(List<T> content) {
this.content = content;
}
@Override
public Sort getSort() {
return sort;
}
public void setSort(Sort sort) {
this.sort = sort;
}
public Page<T> pageImpl() {
return new PageImpl<>(getContent(), new PageRequest(getNumber(),
getSize(), getSort()), getTotalElements());
}
}
关于java - 如何使用 Spring RestTemplate 使用 Page<Entity> 响应,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/34099559/