在DM中的Neo4j Recursivenes

Question

我最近一直致力于我的项目领域模型，其中一个NeoUser可以拥有多个NeoPost。每个Neopost都使用名为user的字段引用其所有者。 现在我注意到当我将Neopost设置为NeoUser.thisusersposts中的条目以及作为用户的NeoImage对象时，我得到递归关系和Stackoverflow错误。

我想要实现的模型应该是这样的：

NEOPOST：

@Id
@GeneratedValue
Long postId;

@NotNull
@NotBlank
@Size(min = 1, max = 600)
String question;

/**
 * Images that are involved in that post
 */
@NotEmpty
@Relationship(type = "STARES", direction = Relationship.OUTGOING)
Set<Neoimage> neoimageSet = new HashSet<>();

/**
 * User that made this post
 */
@Relationship(type = "WAS_CREATED_BY", direction = Relationship.OUTGOING)
NeoUser user;


/**
 * Users that somehow in a way possible described in Userinteractiontype enum
 * with this current post.
 */
@Relationship(type = "INTERACTED_WITH", direction = Relationship.INCOMING)
Set<NeoInteraction> incomingInteractions = new HashSet<>();

NeoUser：

 @Id
@GeneratedValue
Long nodeId;

@Size(min = 2, max = 20, message = "Username length has to be between 2 and 20 characters.")
@Property(name = "user")
String username;

//Relationships / Interactions that were initiated by this user with image of another user
@Relationship(type = "INTERACTED_WITH", direction = Relationship.OUTGOING)
Set<NeoInteraction> outgoingInteraction = new HashSet<>();

//Posts that this user created
@Relationship(type = "OWNS", direction = Relationship.OUTGOING)
Set<NeoPost> thisusersposts = new HashSet<>();

@Relationship(type = "SUBSCRIBED", direction = Relationship.OUTGOING)
Set<NeoUser> usersubscriptions = new HashSet<>();

我现在要问的是：

是否有一些注释可以防止这种递归，从而阻止Stackoverflow错误？非常感谢你。

Answer 1

好吧，我找到了解决问题的方法。 经过数小时的调试，我通过使用Lombok注释排除NeoPost中的用户来消除哈希码中的循环引用：

// firebase access key
define( 'API_ACCESS_KEY', 'AAAAAG78XmM:APA91bFRHpzuEIgiQRmPUm4uRy8bygNGr1h2Oq3ydc5WtKbrfJA8NVAaGIAxbQELfcOWwN2OR4pf5NzSRuuWOYj_P-XXXXXXXX');        
// target device 'fcm' id
$device[0]='JI8YHo7GEo:APA9-aGWOU3U3CXXXXXXXXXXX';
$device[1]='JI8YHo7GEo:APA9-aGWOU3U3CXXXXXXXXXXX';

    $url = 'https://fcm.googleapis.com/fcm/send';

    // "to": "e1w6hEbZn-8:APA91bEUIb2JewYCIiApsMu5JfI5Ak...",   // for single device (insted of "registration_ids"=>"$device"  )
    $data = array("registration_ids" => $device,            // for multiple devices 
        "notification" => array( 
        "title" => "Party Night", 
        "body" => "Invitation for pool party!",
        "message"=>"Come at evening...",
        'icon'=>'https://www.example.com/images/icon.png'
    ),
        "data"=>array(
        "name"=>"xyz",
        'image'=>'https://www.example.com/images/minion.jpg'
        ) 
    ); 

    $data_string = json_encode($data); 
    $headers = array ( 'Authorization: key=' . API_ACCESS_KEY, 'Content-Type: application/json' ); 
    $ch = curl_init(); 
    curl_setopt( $ch,CURLOPT_URL,$url ); 
    curl_setopt( $ch,CURLOPT_POST, true ); 
    curl_setopt( $ch,CURLOPT_HTTPHEADER, $headers ); 
    curl_setopt( $ch,CURLOPT_RETURNTRANSFER, true ); 
    curl_setopt( $ch,CURLOPT_POSTFIELDS, $data_string); 
    $result = curl_exec($ch);