Jackson JSON,不可变的类和接口

| 我正在玩Jackson的示例,并且在进行反序列化以使用不可变的类和接口时遇到一些麻烦。 下面是我的代码:
package com.art.starter.jackson_starter;

import java.io.IOException;
import java.io.StringReader;
import java.io.StringWriter;

import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;
/**  * Hello world!  *  */ public class App  {
    public static void main( String[] args ) throws JsonGenerationException, JsonMappingException, IOException
    {
        System.out.println( \"Hello World!\" );

        AddressImpl.AddressBuilder builder = new AddressImpl.AddressBuilder();
        NameImpl.Builder nameBuilder = new NameImpl.Builder();
        UserImpl.Builder userBuilder = new UserImpl.Builder();


        Name name = nameBuilder.first(\"FirstName\")
                  .last(\"LastName\")
                  .build();

        Address address =  builder.setCity(\"TestCity\")
               .setCountry(\"TestCountry\")
               .setState(\"PA\")
               .setStreet(\"TestAddress\")
               .setZip(123)
               .build();      

        User user = userBuilder.address(address)
                 .gender(User.Gender.MALE)
                 .isVerified(true)
                 .userImage(new byte[5])
                 .build();

        System.out.println(address);        
        System.out.println(name);
        System.out.println(user);

        StringWriter sw = new StringWriter();
        ObjectMapper mapper = new ObjectMapper();
        mapper.writeValue(sw, user);
        System.out.println(sw);


       StringReader sr = new StringReader(\"{\\\"address\\\":{\\\"state\\\":\\\"PA\\\",\\\"country\\\":\\\"TestCountry\\\",\\\"street\\\":\\\"TestAddress\\\",\\\"city\\\":\\\"TestCity\\\",\\\"zip\\\":123},\\\"verified\\\":true,\\\"gender\\\":\\\"MALE\\\",\\\"userImage\\\":\\\"AAAAAAA=\\\"}\");

       /* 
          This line throws the Exception           
       */
       User user2 = mapper.readValue(sr, UserImpl.class);

       System.out.println(user2);
    } }

package com.art.starter.jackson_starter;

import java.util.Arrays;

import org.codehaus.jackson.annotate.JsonCreator;
import org.codehaus.jackson.annotate.JsonProperty;

public final class UserImpl implements User
{
   private final Address address;
   private final Gender gender;
   private final byte[] userImage;
   private final boolean isVerified;

   public static class Builder
   {
      private Address address;
      private Gender gender;
      //      private Name name;
      private byte[] userImage;
      private boolean isVerified;

      public Builder address(Address address)
      {
         this.address = address;
         return this;
      }

      public Builder gender(Gender gender)
      {
         this.gender = gender;
         return this;
      }

      //      public Builder name(Name name)
      //      {
      //         this.name = name;
      //         return this;
      //      }

      public Builder userImage(byte[] userImage)
      {
         this.userImage = userImage;
         return this;
      }

      public Builder isVerified(boolean isVerified)
      {
         this.isVerified = isVerified;
         return this;
      }

      public UserImpl build()
      {
         return new UserImpl(address, gender, userImage, isVerified);
      }
   }

   @JsonCreator
   public UserImpl(@JsonProperty(\"address\") Address address, @JsonProperty(\"gender\") Gender gender, @JsonProperty(\"userImage\") byte[] userImage,
         @JsonProperty(\"verified\") boolean isVerified)
   {
      super();
      this.address = address;
      this.gender = gender;
      this.userImage = userImage;
      this.isVerified = isVerified;
   }

   public Address getAddress()
   {
      return address;
   }

   public Gender getGender()
   {
      return gender;
       }

   public byte[] getUserImage()
   {
      return userImage;
   }

   public boolean isVerified()
   {
      return isVerified;
   }

   @Override
   public String toString()
   {
      StringBuilder builder2 = new StringBuilder();
      builder2.append(\"UserImpl [address=\");
      builder2.append(address);
      builder2.append(\", gender=\");
      builder2.append(gender);
      builder2.append(\", isVerified=\");
      builder2.append(isVerified);
      builder2.append(\", name=\");
      builder2.append(\", userImage=\");
      builder2.append(Arrays.toString(userImage));
      builder2.append(\"]\");
      return builder2.toString();
   }

}

package com.art.starter.jackson_starter;

import org.codehaus.jackson.annotate.JsonCreator;
import org.codehaus.jackson.annotate.JsonProperty;

public final class AddressImpl implements Address
{
   private final String city;
   private final String country;
   private final String street;
   private final String state;
   private final int zip;

   public static class AddressBuilder
   {
      private String city;
      private String country;
      private String street;
      private String state;
      private int zip;

      public AddressBuilder setCity(String city)
      {
         this.city = city;
         return this;
      }

      public AddressBuilder setCountry(String country)
      {
         this.country = country;
         return this;
      }

      public AddressBuilder setStreet(String street)
      {
         this.street = street;
         return this;
      }

      public AddressBuilder setState(String state)
      {
         this.state = state;
         return this;
      }

      public AddressBuilder setZip(int zip)
      {
         this.zip = zip;
         return this;
      }

      public AddressImpl build()
      {
         return new AddressImpl(city, country, street, state, zip);
      }

   }

   @JsonCreator
   public AddressImpl(@JsonProperty(\"city\") String city, @JsonProperty(\"country\") String country, @JsonProperty(\"street\") String street,
         @JsonProperty(\"state\") String state, @JsonProperty(\"zip\") int zip)
   {
      this.city = city;
      this.country = country;
      this.street = street;
      this.state = state;
      this.zip = zip;
   }

   public String getCity()
   {
      return city;
   }

   public String getCountry()
   {
      return country;
   }

   public String getStreet()
   {
      return street;
   }

   public String getState()
   {
      return state;
   }

   public int getZip()
   {
      return zip;
   }

   @Override
   public String toString()
   {
      StringBuilder builder = new StringBuilder();
      builder.append(\"AddressImpl [city=\");
      builder.append(city);
      builder.append(\", country=\");
      builder.append(country);
      builder.append(\", state=\");
      builder.append(state);
      builder.append(\", street=\");
      builder.append(street);
      builder.append(\", zip=\");
      builder.append(zip);
      builder.append(\"]\");
      return builder.toString();
   }

}
问题似乎出在地址上。我得到这个例外:
Exception in thread \"main\" org.codehaus.jackson.map.JsonMappingException: Can not construct instance of com.art.starter.jackson_starter.Address, problem: abstract types can only be instantiated with additional type information
 at [Source: java.io.StringReader@785f8172; line: 1, column: 2]
    at org.codehaus.jackson.map.JsonMappingException.from(JsonMappingException.java:163)
    at org.codehaus.jackson.map.deser.StdDeserializationContext.instantiationException(StdDeserializationContext.java:212)
    at org.codehaus.jackson.map.deser.AbstractDeserializer.deserialize(AbstractDeserializer.java:97)
    at org.codehaus.jackson.map.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:230)
    at org.codehaus.jackson.map.deser.BeanDeserializer._deserializeUsingPropertyBased(BeanDeserializer.java:595)
    at org.codehaus.jackson.map.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:472)
    at org.codehaus.jackson.map.deser.BeanDeserializer.deserialize(BeanDeserializer.java:350)
    at org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:2391)
    at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1614)
    at com.art.starter.jackson_starter.App.main(App.java:56)
我确定这是因为Jackson无法解析地址,而地址是作为具体实现的地址接口的接口。我一直在浏览文档,并查看了有关@JsonDeserialize(as = AddressImpl.class)的几篇文章,但是没有用。所以我很沮丧。有没有人让它起作用,甚至得到了支持吗? 如果我在
UserImpl
类中将
Address
替换为
AddressImpl
,它将像冠军一样工作。     
已邀请:
        以防万一您没有看到它,这是一个博客条目,讨论使用不可变对象和Jackson。 但是通过将ѭ5添加到Address.java接口(直接或通过混合使用),或将其添加到字段或属性,您肯定应该能够使用ѭ5。要注意的一件事是,对于反序列化,它必须在您使用的访问器旁边;如果您在字段旁边有一个,则使用setter。注释尚未(在访问者之间)共享;因此例如将其添加到\'getter \'将不起作用。 杰克逊1.8最终还允许注册从抽象到具体的类型(有关更多详细信息,请参见http://jira.codehaus.org/browse/JACKSON-464),这可能是表明\'AddressImpl \'的最佳选择。用于\'地址\'。     

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