Question

使用弹簧启动设计新应用程序时。我希望有一个休息终点来找到所有具有下面过滤器的实体

获取http://foo.com/entities?firstName=test&lastName=test2

实现如下所示。

@RequestMapping(value = /entities, method = RequestMethod.GET)
public List<Entity> getAll(@RequestParam(value = "firstName", required = false) String firstName, @RequestParam(value = "lastName", required = false) String lastName) {
  if (firstName != null && lastName != null) {
    return entityRepository.findByFirstNameAndLastName(firstName, lastName);
  } else if (firstName != null) {
    return entityRepository.findByFirstName(firstName);
  } else if (lastName != null) {
    return entityRepository.findByLastName(lastName);
  } else {
    return StreamSupport.stream(entityRepository.findAll().spliterator(), false).collect(Collectors.toList());
  }
}

如果我们必须添加新参数，我们可以看到这有点失控。减轻这种情况的最简单方法是什么？或者我应该改变设计。我认为这是标准做法？

请注意。存储库是一个带有添加方法的CRUDRepository。

Answer 1

我认为您应该创建某种“SearchUtils”并使用Criteria API。例如：

public class SearchCriteria {

public SearchCriteria() {
}

private String firstName;

private String lastName;

public String getFirstName() {
    return firstName;
}

public void setFirstName(String firstName) {
    this.firstName = firstName;
}

public String getLastName() {
    return lastName;
}

public void setLastName(String lastName) {
    this.lastName = lastName;
}

}

SearchUtils类：

public class SearchUtils {


List<Entity> search(SearchCriteria criteria){

    //use Criteria API here



}

}

和控制器：

@RequestMapping(value = /entities, method = RequestMethod.GET)
public List<Entity> getAll(@Valid SearchCriteria searchCriteria) 
{
return searchUtils.search(searchCriteria);
}

详细了解CriteriaAPI here或here

Answer 2

此处记录了前进的方向 https://docs.spring.io/spring-data/jpa/docs/current/reference/html/#query-by-example

使用Spring Web和数据过滤findAll

2 个答案: