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copied!<p>There's a few parts implicit to your question, and it's not clear where you're having trouble:</p> <ol> <li>How do you take a JSON string and make usable Java objects out of it. (I'm assuming Java, not JavaScript, since you've tagged your question with "java".)</li> <li>How do you sort those objects after they're made?</li> <li>How do you handle sorting the nested parts? (In your example, "idx-server" has sub-tenants.)</li> </ol> <p>Not sure exactly which parts of this you're having trouble with, so here's some notes for all three.</p> <p>Part 1: Getting Java objects</p> <p>I agree with the other guy that <a href="http://jackson.codehaus.org/" rel="nofollow">Jackson</a> is a good JSON parser to use. Here's a couple lines of code you could use to parse some JSON:</p> <pre><code>String jsonString = "..."; // Load this in whatever way makes sense for you ObjectMapper mapper = new ObjectMapper(); Map<String,Object> parsedJson = mapper.readValue(jsonString, Map.class); </code></pre> <p>If your JSON string is really huge, then there are other <code>readValue</code> overloads that you can use to avoid reading the whole String into memory.</p> <p>Part 2: Sorting Java objects</p> <p>Once you've got the parsed JSON, sorting is just a matter of calling <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Collections.html#sort%28java.util.List,%20java.util.Comparator%29" rel="nofollow"><code>Collections.sort(...)</code></a>, passing in the <code>tenants</code> array. Plus you'll need to write a <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Comparator.html" rel="nofollow">Comparator</a> that defines the ordering that you want. For example, here's a comparator that sorts by name:</p> <pre><code>public class NameComparator implements Comparator<Map<String,Object>> { public int compare(Map<String,Object> o1, Map<String,Object> o2) { String name1 = (String) o1.get("name"); String name2 = (String) o2.get("name"); return name1.compareTo(name2); } } </code></pre> <p>Then you get the tenants array out (Jackson makes them into <a href="http://docs.oracle.com/javase/6/docs/api/java/util/ArrayList.html" rel="nofollow"><code>ArrayList</code></a> objects) and call <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Collections.html#sort%28java.util.List,%20java.util.Comparator%29" rel="nofollow"><code>Collections.sort(...)</code></a>. For example,</p> <pre><code>List<Map<String,Object>> tenants = (List<Map<String,Object>>) parsedJson.get("tenants"); Collections.sort(tenants, new NameComparator()); </code></pre> <p>Part 3: Handling the nesting</p> <p>The clearest way to do this is to add some extra code to walk through your JSON looking for any object with a tenants array, and sort it. For example, here's a recursive function that should do it:</p> <pre><code>public static void recursiveSortTenants(Map<String,Object> jsonObject) { List<Map<String,Object>> tenants = (List<Map<String,Object>>) jsonObject.get("tenants"); if (tenants != null) { Collections.sort(tenants, new NameComparator()); // For each tenant, see if it has sub-tenants. If so, // call this function again to sort them. for (Map<String,Object> tenant : tenants) { if (tenants.containsKey("tenants")) { recursiveSortTenants(tenant); } } } } </code></pre> <p>Hope this helps!</p>

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