Jenkins usage data parser

UsageData.java

package org.jenkinsci.tools;

import java.io.File;
import java.io.IOException;

import org.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonParseException;
import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.JsonToken;

public class UsageData {

    public UsageData(final String filename, final String pluginName) throws JsonParseException, IOException {
        JsonFactory jsonFactory = new JsonFactory();
        JsonParser jp = jsonFactory.createJsonParser(new File(filename));

        int installCount = 0;
        int pluginCount = 0;

        String name;
        JsonToken token;
        boolean inPluginArray = false;
        boolean pluginSeen = false;
        while (jp.nextToken() != null) {
            token = jp.getCurrentToken();

            switch (token) {
            case VALUE_STRING:
                break;
            case START_ARRAY:
                if (jp.getCurrentName().equals("plugins")) {
                    inPluginArray = true;
                }
                break;
            case END_ARRAY:
                inPluginArray = false;
                break;
            default:
                // Skip all other token types
                continue;
            }

            name = jp.getCurrentName();
            if (token == JsonToken.START_ARRAY && name.length() == 64) {
                // Found list of reports for a new installation
                installCount++;
                pluginSeen = false;
            }

            if (!pluginSeen && inPluginArray && token == JsonToken.VALUE_STRING && name.equals("name")) {
                if (jp.getText().equals(pluginName)) {
                    pluginCount++;
                    pluginSeen = true;
                }
            }
        }
        jp.close();

        System.out.println("Total install count: "+ installCount);
        System.out.println(pluginName +" count:  "+ pluginCount);
    }

    public static void main(String[] args) throws JsonParseException, IOException {
        new UsageData("201108.json", "ssh-slaves");
    }

}