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copied!<blockquote> <p><em>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?</em></p> </blockquote> <p><a href="http://code.google.com/p/google-gson/" rel="noreferrer">Google Gson</a> supports generics and nested beans. The <code>[]</code> in JSON represents an array and should map to a Java collection such as <a href="http://docs.oracle.com/javase/6/docs/api/java/util/List.html" rel="noreferrer"><code>List</code></a> or just a plain Java array. The <code>{}</code> in JSON represents an object and should map to a Java <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Map.html" rel="noreferrer"><code>Map</code></a> or just some JavaBean class.</p> <p>You have a JSON object with several properties of which the <code>groups</code> property represents an array of nested objects of the very same type. This can be parsed with Gson the following way:</p> <pre><code>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); } } </code></pre> <p>Fairly simple, isn't it? Just have a suitable JavaBean and call <a href="http://google-gson.googlecode.com/svn/tags/1.3/docs/javadocs/com/google/gson/Gson.html#fromJson%28java.lang.String,%20java.lang.Class%29" rel="noreferrer"><code>Gson#fromJson()</code></a>.</p> <h3>See also:</h3> <ul> <li><a href="http://json.org/" rel="noreferrer">Json.org</a> - Introduction to JSON</li> <li><a href="https://github.com/google/gson/blob/master/UserGuide.md" rel="noreferrer">Gson User Guide</a> - Introduction to Gson</li> </ul>

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