Question 109024 in Json Question posted in
Our archive of expertly curated questions and answers provides insights and solutions to common problems related to this popular data interchange format. From parsing and manipulating JSON data to integrating it with various programming languages and web services, our archive has got you covered. Start exploring today and take your JSON skills to the next level

@JsonIgnore does not ignore fields I do not want displaying

This is roughly my code.

I am trying to have Jackson ignore a field when it takes my POJO and creates JSON out of it:

    
import com.fasterxml.jackson.annotation.JsonIgnore;

public class MyPOJO {

    @JsonIgnore
    private String socialSecurityNumber = "111-11-1111";

    // ...

    public String getSocialSecurityNumber() {
        return socialSecurityNumber;
    }

    // ...
}

import java.util.ArrayList;
import java.util.List;
import java.io.IOException;

import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;

public class FormatAlerts {
    List<Message> alerts = new ArrayList<>();

    public FormatAlerts(List<Message>alerts) {
        this.alerts = alerts;
    }

    public List<String> formatAlerts() {
        List<String> formattedAlerts = new ArrayList<>();

        ObjectMapper om = new ObjectMapper();
        try {
            for(Message m : alerts) {
                String alert = om.defaultPrettyPrintingWriter()
                        .writeValueAsString(m);
                formattedAlerts.add(alert);
            }
        } catch(Exception e) {
            e.printStackTrace();
        }

        return formattedAlerts;
    }
}

The JSON is ouputted fine, but the class members that have @JsonIgnore are NOT ignored.

I have these dependencies in my Maven pom.xml

<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.codehaus.jackson</groupId>
        <artifactId>jackson-xc</artifactId>
        <version>1.9.12</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.14.2</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>2.14.2</version>
    </dependency>
</dependencies>

Those are my only Jackson and Json entries in my pom.xml

Do I need a different combination of versions?

Tags:

2

Answers


  1. 0

    Please add the jackson dependencies as follows. Remove the others.

    <dependency> 
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-core</artifactId>
  <version>2.14.2</version>
</dependency>
<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-annotations</artifactId>
  <version>2.14.2</version>
</dependency>
<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>
  <version>2.14.2</version>
</dependency>
    Login or Signup to reply.
  2. 0

    Long story short, you are mixing two incompatible libraries.

    Jackson project was originally started under Codehaus project, but at least 10 years ago it was moved.

    The jackson-xc released in 2013 under org.codehaus namespace.
    You are using an ObjectMapper in FormatAlerts

    import org.codehaus.jackson.map.ObjectMapper;

    That kind of ObjectMapper using own @JsonIgnore annotation which placed under org.codehaus.jackson.annotate.JsonIgnore.

    In fact, the ObjectMapper from org.codehaus project doesn’t recognize the @JsonIgnore annotaion from com.fasterxml namespace.

    You should consolidate those project. I strongly recommend use com.fasterxml because org.codehaus is no longer maintained.

    Step 1.

    <dependency>
    <groupId>org.codehaus.jackson</groupId>
    <artifactId>jackson-xc</artifactId>
    <version>1.9.12</version>
</dependency>

    was moved to

    <dependency>
    <groupId>com.fasterxml.jackson.module</groupId>
    <artifactId>jackson-module-jaxb-annotations</artifactId>
    <version>2.14.2</version>
</dependency>

    Step 2.

    Now, the right dependency included, but it has some changes.

    Import ObjectMapper from the right package

    import com.fasterxml.jackson.databind.ObjectMapper;

    Don’t worry it also have pretty print feature, but the method name changed.

    public List<String> formatAlerts() {
    List<String> formattedAlerts = new ArrayList<>();

    // be sure it's imported from com.fasterxml.jackson.databind.ObjectMapper;
    ObjectMapper om = new ObjectMapper();

    try {
        for(Message m : alerts) {
            // changed from om.defaultPrettyPrintingWriter()
            String alert = om.writerWithDefaultPrettyPrinter()
                    .writeValueAsString(m);
            formattedAlerts.add(alert);
        }
    } catch(Exception e) {
        e.printStackTrace();
}
    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search