JSON Formatting with Jersey and Jackson

[James Dekker]

Using Java 6, Tomcat 7, Jersey 1.15, Jackson 1.9.9, created a simple web service which has the following architecture:

My POJOs (model classes):

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Family {

	private String father;
	private String mother;
	
	private List<Children> children;
		
	// Getter & Setters
}

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Children {
	
	private String name;
	private String age;
	private String gender;
	
	// Getters & Setters
}

Using a Utility Class, I decided to hard code the POJOs as follows:

public class FamilyUtil {
	public static Family getFamily() {
		Family family = new Family();
		family.setFather("Joe");
		family.setMother("Jennifer");
		
		Children child = new Children();
		child.setName("Jimmy");
		child.setAge("12");
		child.setGender("male");
		List<Children> children = new ArrayList<Children>();
		
		children.add(child);
		
		family.setChildren(children);
		return family;
	}
}

MyWebService:

@Path("")
public class MyWebService {
	
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public Family getFamily {
		return FamilyUtil.getFamily();
	}
}

Produces:

{ "children": [{"age":"12","gender":"male","name":"Jimmy"}],"father":"Joe", "mother":"Jennifer"}

What I need to do is have it produce it in a more legible manner:

{ 
	"father":"Joe", 
	"mother":"Jennifer",
	"children": 
	[
		{
			"name":"Jimmy",
			"age":"12","
            "gender":"male"
		}
	]
}

Just am seeking a way to implement so it can display some type of formatting with indentation / tabs.

Would be very grateful if someone could assist me.

Thank you for taking the time to read this.

[Praful Thakare]

have you tried any json libraries ?

1) googles json lib
2) JSON try toString method from this lib.

-P

[James Dekker]

Praful,

Thanks for the response!

When I tried this:

@GET
@Produces(MediaType.APPLICATION_JSON)
public Family getFamily() throws JsonGenerationException, JsonMappingException, IOException {
     ObjectMapper mapper = new ObjectMapper();
	 mapper.configure(SerializationConfig.Feature.INDENT_OUTPUT, true); 
	 return mapper.readValue(mapper.writeValueAsString(FamilyUtil.getFamily()), FamilyUtil.getFamily().getClass());
}

Using the curl command in Linux (this is my actual web service client):

curl -X GET http://localhost:8080/mywebservice

This is the response I got:

{"children":[{"age":"12","gender":"male","name":"Jimmy"}],"father":"Joe","mother":"Jennifer"}

Doesn't seem like anything happened...

Here are the dependencies listed in my pom.xml file:

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.0.6</version>
</dependency>

<dependency>
     <groupId>com.fasterxml.jackson.core</groupId>
     <artifactId>jackson-annotations</artifactId>
     <version>2.0.6</version>
</dependency>

<dependency>
     <groupId>com.fasterxml.jackson.core</groupId>
     <artifactId>jackson-databind</artifactId>
     <version>2.0.6</version>
</dependency>

Does anyone know what I am possibly doing wrong?

[Praful Thakare]

I have not used fasterxml.jackson so no idea about it, try this

 <dependency>
      <groupId>com.google.code.gson</groupId>
      <artifactId>gson</artifactId>
      <version>2.2.2</version>
      <scope>compile</scope>
    </dependency>

@Path("")  
public class MyWebService {  
      
    @GET  
    @Produces(MediaType.APPLICATION_JSON)  
    public String getFamily {  
         Gson gson = new GsonBuilder().setPrettyPrinting().create();
        String jsonOutput = gson.toJson( FamilyUtil.getFamily());

        return jsonOutput;
    }  
}  
 
  

NOTE:- Retrun Type is String now
I get following output

$ curl -X GET http://xbox.localhost:8080/MYAPP/rest//getFamily
{
  "father": "Joe",
  "mother": "Jennifer",
  "children": [
    {
      "name": "Jimmy",
      "age": "12",
      "gender": "male"
    }
  ]
}

Also, are you sure you paste correct code? I checked the online API of fasterxml and there is nothing like SerializationConfig.Feature.INDENT, it is SerializationConfigFeature.INDENT

-P