Jackson JSON处理器在反序列化过程中覆盖对象的属性

Question

我有一个有趣的问题。 Jackson使用具有相同名称的'child'对象的属性值覆盖'父'对象上的属性值。所以，更确切地说，这是Java的结构，我有

public class Contact { 
    ... 
    String name; 
    List<Email> emails; 
    List<PhoneNumbers> phoneNumbers; 
    Account account; 
    ... 
} 

public class Account { 
    ... 
    String accountName; 
    List<Email> emails; 
    List<PhoneNumbers> phoneNumbers; 
    Account account; 
    ... 
} 

所以，当我形成联系JSON对象，并将其发送到服务器，一切都很正常，直到BeanDeserializer进入Contact类的帐户属性。然后，它开始读取JSON账户部分的proeprties，这是可以的，但不会创建Account实例来设置联系人 - 它将账户属性的值写入具有相同Contact名称的属性中。

我很困惑，不知道从哪里开始寻找如何解决这个问题。

Answer 1

我无法重现与原始问题中描述的相似的任何问题。

以下基于原始问题描述创建的示例按预期工作，没有错误或不正确的反序列化。

import java.util.LinkedList; 
import java.util.List; 

import org.codehaus.jackson.annotate.JsonAutoDetect.Visibility; 
import org.codehaus.jackson.annotate.JsonCreator; 
import org.codehaus.jackson.annotate.JsonProperty; 
import org.codehaus.jackson.map.ObjectMapper; 

public class JacksonFoo 
{ 
    public static void main(String[] args) throws Exception 
    { 
    Account account1 = new Account(); 
    account1.accountName = "account 1"; 
    account1.emails = new LinkedList<Email>(); 
    account1.emails.add(new Email("email_11@google.com")); 
    account1.emails.add(new Email("email_12@google.com")); 
    account1.phoneNumbers = new LinkedList<PhoneNumbers>(); 
    account1.phoneNumbers.add(new PhoneNumbers(1111, 1112)); 
    account1.phoneNumbers.add(new PhoneNumbers(1113, 1114)); 

    Account account2 = new Account(); 
    account2.accountName = "account 2"; 
    account2.emails = new LinkedList<Email>(); 
    account2.emails.add(new Email("email_21@google.com")); 
    account2.emails.add(new Email("email_22@google.com")); 
    account2.phoneNumbers = new LinkedList<PhoneNumbers>(); 
    account2.phoneNumbers.add(new PhoneNumbers(2221, 2222)); 
    account2.phoneNumbers.add(new PhoneNumbers(2223, 2224)); 
    account2.account = account1; 

    Contact contact = new Contact(); 
    contact.name = "contact"; 
    contact.emails = new LinkedList<Email>(); 
    contact.emails.add(new Email("email_31@google.com")); 
    contact.emails.add(new Email("email_32@google.com")); 
    contact.phoneNumbers = new LinkedList<PhoneNumbers>(); 
    contact.phoneNumbers.add(new PhoneNumbers(3331, 3332)); 
    contact.phoneNumbers.add(new PhoneNumbers(3333, 3334)); 
    contact.account = account2; 

    ObjectMapper mapper = new ObjectMapper(); 
    mapper.setVisibilityChecker( 
     mapper.getVisibilityChecker() 
      .withFieldVisibility(Visibility.ANY)); 

    String account1Json = mapper.writeValueAsString(account1); 
    String account2Json = mapper.writeValueAsString(account2); 
    String contactJson = mapper.writeValueAsString(contact); 

    System.out.println(account1Json); // {"accountName":"account 1","emails":[{"email":"email_11@google.com"},{"email":"email_12@google.com"}],"phoneNumbers":[{"phone1":1111,"phone2":1112},{"phone1":1113,"phone2":1114}],"account":null} 
    System.out.println(account2Json); // {"accountName":"account 2","emails":[{"email":"email_21@google.com"},{"email":"email_22@google.com"}],"phoneNumbers":[{"phone1":2221,"phone2":2222},{"phone1":2223,"phone2":2224}],"account":{"accountName":"account 1","emails":[{"email":"email_11@google.com"},{"email":"email_12@google.com"}],"phoneNumbers":[{"phone1":1111,"phone2":1112},{"phone1":1113,"phone2":1114}],"account":null}} 
    System.out.println(contactJson); // {"name":"contact","emails":[{"email":"email_31@google.com"},{"email":"email_32@google.com"}],"phoneNumbers":[{"phone1":3331,"phone2":3332},{"phone1":3333,"phone2":3334}],"account":{"accountName":"account 2","emails":[{"email":"email_21@google.com"},{"email":"email_22@google.com"}],"phoneNumbers":[{"phone1":2221,"phone2":2222},{"phone1":2223,"phone2":2224}],"account":{"accountName":"account 1","emails":[{"email":"email_11@google.com"},{"email":"email_12@google.com"}],"phoneNumbers":[{"phone1":1111,"phone2":1112},{"phone1":1113,"phone2":1114}],"account":null}}} 

    Account account1Copy = mapper.readValue(account1Json, Account.class); 
    Account account2Copy = mapper.readValue(account2Json, Account.class); 
    Contact contactCopy = mapper.readValue(contactJson, Contact.class); 

    System.out.println(account1.equals(account1Copy)); // true 
    System.out.println(account2.equals(account2Copy)); // true 
    System.out.println(contact.equals(contactCopy)); // true 
    } 
} 

class Contact 
{ 
    String name; 
    List<Email> emails; 
    List<PhoneNumbers> phoneNumbers; 
    Account account; 

    @Override 
    public boolean equals(Object o) 
    { 
    Contact c = (Contact) o; 
    if (name.equals(c.name)) 
     if (emails.containsAll(c.emails)) 
     if (c.emails.containsAll(emails)) 
      if (phoneNumbers.containsAll(c.phoneNumbers)) 
      if (c.phoneNumbers.containsAll(phoneNumbers)) 
       return account.equals(c.account); 
    return false; 
    } 
} 

class Account 
{ 
    String accountName; 
    List<Email> emails; 
    List<PhoneNumbers> phoneNumbers; 
    Account account; 

    @Override 
    public boolean equals(Object o) 
    { 
    Account a = (Account) o; 
    if (accountName.equals(a.accountName)) 
     if (emails.containsAll(a.emails)) 
     if (a.emails.containsAll(emails)) 
      if (phoneNumbers.containsAll(a.phoneNumbers)) 
      if (a.phoneNumbers.containsAll(phoneNumbers)) 
       if (account != null && a.account != null) 
       return account.equals(a.account); 
       else if (account == null && a.account == null) 
       return true; 
    return false; 
    } 
} 

class Email 
{ 
    String email; 

    @JsonCreator 
    Email(@JsonProperty("email") String e) {email = e;} 

    @Override 
    public boolean equals(Object o) 
    { 
    Email e = (Email) o; 
    return email.equals(e.email); 
    } 
} 

class PhoneNumbers 
{ 
    long phone1; 
    long phone2; 

    @JsonCreator 
    PhoneNumbers(@JsonProperty("phone1") long p1, @JsonProperty("phone2")long p2) {phone1 = p1; phone2 = p2;} 

    @Override 
    public boolean equals(Object o) 
    { 
    PhoneNumbers p = (PhoneNumbers) o; 
    return phone1 == p.phone1 && phone2 == p.phone2; 
    } 
}