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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