Google GSON does this; I've used it on several projects and it's simple and works well. It can do the translation for simple objects with no intervention, but there's a mechanism for customizing the translation (in both directions,) as well.

Gson g = ...;
String jsonString = g.toJson(new Customer());

JSONObject json = new JSONObject(yourdata);
String statistics = json.getString("statistics");
JSONObject name1 = json.getJSONObject("John");
String ageJohn = name1.getString("Age");

For getting those items in a dynamic way:

JSONObject json = new JSONObject(yourdata);
String statistics = json.getString("statistics");

for (Iterator key=json.keys();key.hasNext();) {
    JSONObject name = json.get(key.next());
    //now name contains the firstname, and so on... 
}

It's usually a good idea to separate the serialization method (JSON) from your business logic so that if in the future you decide to use some other type of serialization, you can do so without affecting the business logic.

Jackson is probably the most popular open-source library for JSON serialization/deserialization in Java.

In the situation where some amount of transformation is needed between the data received from your customer database and what you actually return to the caller, I usually create a separate DTO (data-transfer object) class that contains only the fields to be serialized.

On the other hand, if you always need to remove the same fields from the customer data before transmittal and don't mind putting serialization-specific annotations on your POJOs, you can use Jackson's @JsonIgnore (or similar) on those fields and skip the DTO.

I looked at Google's Gson as a potential JSON plugin. Can anyone offer some form of guidance as to how I can generate Java from this JSON string?

Google Gson supports generics and nested beans. The [] in JSON represents an array and should map to a Java collection such as List or just a plain Java array. The {} in JSON represents an object and should map to a Java Map or just some JavaBean class.

You have a JSON object with several properties of which the groups property represents an array of nested objects of the very same type. This can be parsed with Gson the following way:

package com.stackoverflow.q1688099;

import java.util.List;
import com.google.gson.Gson;

public class Test {

    public static void main(String... args) throws Exception {
        String json = 
            "{"
                + "'title': 'Computing and Information systems',"
                + "'id' : 1,"
                + "'children' : 'true',"
                + "'groups' : [{"
                    + "'title' : 'Level one CIS',"
                    + "'id' : 2,"
                    + "'children' : 'true',"
                    + "'groups' : [{"
                        + "'title' : 'Intro To Computing and Internet',"
                        + "'id' : 3,"
                        + "'children': 'false',"
                        + "'groups':[]"
                    + "}]" 
                + "}]"
            + "}";

        // Now do the magic.
        Data data = new Gson().fromJson(json, Data.class);

        // Show it.
        System.out.println(data);
    }

}

class Data {
    private String title;
    private Long id;
    private Boolean children;
    private List<Data> groups;

    public String getTitle() { return title; }
    public Long getId() { return id; }
    public Boolean getChildren() { return children; }
    public List<Data> getGroups() { return groups; }

    public void setTitle(String title) { this.title = title; }
    public void setId(Long id) { this.id = id; }
    public void setChildren(Boolean children) { this.children = children; }
    public void setGroups(List<Data> groups) { this.groups = groups; }
    
    public String toString() {
        return String.format("title:%s,id:%d,children:%s,groups:%s", title, id, children, groups);
    }
}

Fairly simple, isn't it? Just have a suitable JavaBean and call Gson#fromJson().

See also:

• Json.org - Introduction to JSON
• Gson User Guide - Introduction to Gson