json to pojo java example

How to convert the following JSON String to POJO

stackoverflow.com › questions › 41499935 › how-to-convert-the-following-json-string-to-pojo

I think it should work. I've executed this code and it works fine. Here is my example.

import com.fasterxml.jackson.databind.ObjectMapper;
import java.io.IOException;

public class TestJackson {

public static void main(String[] args) throws IOException {
        ObjectMapper mapper = new ObjectMapper();
        String testJson = "{\n" + "  \"user\": {\n" + "    \"0\": {\n" + "      \"firstName\": \"Monica\",\n" + "      \"lastName\": \"Belluci\"\n" + "    },\n" + "    \"1\": {\n" + "      \"firstName\": \"John\",\n" + "      \"lastName\": \"Smith\"\n" + "    },\n" + "    \"2\": {\n" + "      \"firstName\": \"Owen\",\n" + "      \"lastName\": \"Hargreaves\"\n" + "    }\n" + "  }\n" + "}";
        User readValue = mapper.readValue(testJson, User.class);
        System.out.println("readValue = " + readValue);
    }
}

and the User.class:

import java.util.HashMap;
import java.util.Map;

class User {
    private Map<String, MyObject> user = new HashMap<String, MyObject>();

    public Map<String, MyObject> getUser() {
        return user;
    }

    public void setUser(Map<String, MyObject> user) {
        this.user = user;
    }

    @Override
    public String toString() {
        return "User{" +
                "user=" + user +
                '}';
    }
}

class MyObject {
    private String firstName;
    private String lastName;

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    @Override
    public String toString() {
        return "MyObject{" +
                "firstName='" + firstName + '\'' +
                ", lastName='" + lastName + '\'' +
                '}';
    }
}

Answer from K. Gol on Stack Overflow

Json2CSharp

json2csharp.com › code-converters › json-to-pojo

Convert JSON to POJO Objects in Java Online

Here's how you can convert your JSON string to JAVA objects, we will be using the converter and external libraries like Jackson objectmapper to parse our object. You can find the source code for this example: HERE · Make sure that your JSON object is not large (over 5MB) and is formatted. You can use any JSON format validator online. You can choose from the settings to format the POJOs ...

Jsonschema2pojo

jsonschema2pojo.org

jsonschema2pojo

Using the format rule for a property can influence the Java type chosen to represent your property values. When you use a format value that jsonschema2pojo recognises, it will use a better (more appropriate) type for your Java bean property. For example, when I define a JSON property in my schema of type string, if I also attach the rule "format" : "uri" to that property (because my string is actually a URI) then my corresponding Java property will now have the type java.net.URI instead of java.lang.String.

Discussions

java - How to convert the following JSON String to POJO - Stack Overflow

I had one additional issue, that i faced when converting JSON to Java POJO: com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of class out of START_ARRAY token ... More on stackoverflow.com

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