查询 Hazelcast 分层树结构

Question

我正在尝试了解如何在 Hazelcast 中查询分层树结构。假设我有一个组织 class:

public class Organization {
  private long id;
  private long parentId;
}

我有一个用户 class:

public class NestupUser extends BaseEntity {
  private long id;
  private String firstName;
  private String lastName;
  private String email;
  private String password;
  private long organizationId;
}

现在，给定一个 organizationId，我想找到该组织的所有用户以及以该组织为父级的所有组织，以这些组织为父级的所有组织，等等。

我假设这会像某种 MapReduce 一样工作，但是是否有可能作为一个 MapReduce 的一部分启动更多的 MapReduce 任务？

感谢任何帮助。

Answer 1

我最终构建了一个非规范化的多图，因此我可以找到给定组织 ID 的所有可访问组织。这是在启动时设置结构的代码，如果它还没有被另一个节点设置的话。 class 还实现了入口侦听器接口，以便在事情发生变化时获得回调以保持结构同步（未显示，但不难做到）：

@PostConstruct
public void init() {
    IMap<String, Organization> organizationMap = organizationService.getMap();
    listenerRegistration = organizationMap.addLocalEntryListener(this);
    MultiMap<String, String> orgStructureMap = getOrgStructureMap();
    if (orgStructureMap.keySet().size() == 0) {
        Collection<Organization> all = organizationService.getAll(null);
        Set<String> visited = new HashSet<>();
        for (Organization next : all) {
            if (!visited.contains(next.getId())) {
                while (next != null && next.getParentId() != null && !visited.contains(next.getParentId())) {
                    next = next.getParentOrganization();
                }
                recurseReferences(visited, next);
            }
        }
    }
}

private void recurseReferences(Set<String> visited, Organization org) {
    addAllReferences(org);
    visited.add(org.getId());
    Set<Organization> childOrganizations = org.getChildOrganizations();
    for (Organization child : childOrganizations) {
        recurseReferences(visited, child);
    }
}

private void addAllReferences(Organization organization) {
    MultiMap<String, String> orgStructureMap = getOrgStructureMap();
    String parentId = organization.getParentId();
    if (parentId != null) {
        Set<Map.Entry<String, String>> entries = orgStructureMap.entrySet();
        for (Map.Entry<String, String> next : entries) {
            if (next.getValue().equals(parentId)) {
                orgStructureMap.put(next.getKey(),organization.getId());
            }
        }
    }
    orgStructureMap.put(organization.getId(), organization.getId());
}



private void removeAllReferences(Organization organization) {
    MultiMap<String, String> orgStructureMap = getOrgStructureMap();
    Set<String> keys = orgStructureMap.keySet();
    for (String key : keys) {
        orgStructureMap.remove(key, organization.getId());
    }
}

查询 Hazelcast 分层树结构

Querying Hazelcast hierarchical tree structures

mapreduce

hazelcast