Swing client to expose Cassandra java driver internals in tests

SwingClient.java

package com.datastax.driver.core;

import java.awt.Component;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Iterator;
import java.util.Set;

import javax.swing.*;

import com.datastax.driver.core.policies.LoadBalancingPolicy;

/**
 * To use from your test class:
 * 
 * 1) build your cluster as usual
 * 2) new SwingClient(cluster);
 */
public class SwingClient {
    private static final String DEFAULT_QUERY = "SELECT release_version FROM system.local";

    private final Cluster cluster;
    private final Session session;

    private final Gui gui;

    public SwingClient(Cluster cluster) {
        this.cluster = cluster;
        session = cluster.connect();
        gui = new Gui();
    }

    private void executeQuery() {
        ResultSet rs = session.execute(gui.getQuery());
        for (Row row : rs) {
            gui.output("%s%n", row.toString());
        }
    }

    private void getNodesStatuses() {
        Set<Host> hosts = cluster.getMetadata().getAllHosts();
        for (Host host : hosts) {
            HostDistance distance = cluster.getConfiguration().getPolicies().getLoadBalancingPolicy().distance(host);
            boolean isReconnectingFromSuspected = host.getInitialReconnectionAttemptFuture() != null && !host.getInitialReconnectionAttemptFuture().isDone();
            boolean isReconnectingFromDown = host.getReconnectionAttemptFuture() != null && !host.getReconnectionAttemptFuture().isDone();
            gui.output("[%s:%s:%s] version=%s, state=%s, dist=%s, reconnectFromSuspected=%s, reconnectFromDown=%s%n",
                host.getDatacenter(), host.getRack(), host.getAddress(),
                host.getCassandraVersion(),
                host.state,
                distance,
                isReconnectingFromSuspected,
                isReconnectingFromDown);
        }
    }

    private void computeQueryPlan() {
        gui.output("Query plan: ");
        LoadBalancingPolicy lbp = cluster.getConfiguration().getPolicies().getLoadBalancingPolicy();
        Iterator<Host> iter = lbp.newQueryPlan(null, new SimpleStatement(""));
        while (iter.hasNext()) {
            Host host = iter.next();
            gui.output("%s ", host);
        }
        gui.output("%n");
    }

    private void checkControlConnection() {
        ControlConnection connection = cluster.manager.controlConnection;
        if (connection.isOpen()) {
            gui.output("Control connection is open to %s%n", connection.connectedHost());
        } else {
            gui.output("Control connection is closed%n");
        }

    }

    class Gui {
        private JTextArea queryField;
        private JTextArea outputField;

        Gui() {
            SwingUtilities.invokeLater(new Runnable() {
                public void run() {
                    createAndShow();
                }
            });
        }

        void output(String format, Object... args) {
            outputField.append(String.format(format, args));
        }

        String getQuery() {
            return queryField.getText();
        }

        private void createAndShow() {
            JFrame frame = new JFrame("Cassandra Java driver");

            Container pane = frame.getContentPane();
            pane.setLayout(new BoxLayout(pane, BoxLayout.Y_AXIS));

            createQueryPanel(pane);
            createCommandsPanel(pane);
            createOutputPanel(pane);

            frame.pack();
            frame.setVisible(true);
        }

        private void createQueryPanel(Container pane) {
            JPanel panel = new JPanel();
            panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
            panel.setBorder(BorderFactory.createTitledBorder("Query"));
            pane.add(panel);

            queryField = new JTextArea(4, 50);
            queryField.setText(DEFAULT_QUERY);
            queryField.setLineWrap(true);
            JScrollPane scrollPane = new JScrollPane(queryField);
            panel.add(scrollPane);

            createButton(panel, "Run", new ActionListener() {
                public void actionPerformed(ActionEvent event) {
                    executeQuery();
                }
            }).setAlignmentX(Component.RIGHT_ALIGNMENT);
        }

        private void createCommandsPanel(Container pane) {
            JPanel panel = new JPanel();
            panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));
            createButton(panel, "Query plan", new ActionListener() {
                public void actionPerformed(ActionEvent event) {
                    computeQueryPlan();
                }
            });

            createButton(panel, "Hosts", new ActionListener() {
                public void actionPerformed(ActionEvent event) {
                    getNodesStatuses();
                }
            });
            pane.add(panel);

            createButton(panel, "Control Cnx", new ActionListener() {
                public void actionPerformed(ActionEvent event) {
                    checkControlConnection();
                }
            });
            pane.add(panel);
        }

        private void createOutputPanel(Container pane) {
            JPanel panel = new JPanel();
            panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
            panel.setBorder(BorderFactory.createTitledBorder("Output"));
            pane.add(panel);

            outputField = new JTextArea(8, 100);
            outputField.setLineWrap(true);
            outputField.setEditable(false);
            JScrollPane scrollPane = new JScrollPane(outputField);
            panel.add(scrollPane);

            createButton(panel, "Clear", new ActionListener() {
                public void actionPerformed(ActionEvent event) {
                    outputField.setText("");
                }
            }).setAlignmentX(Component.RIGHT_ALIGNMENT);
        }

        private JButton createButton(Container container, String label, ActionListener action) {
            JButton button = new JButton(label);
            button.addActionListener(action);
            container.add(button);
            return button;
        }
    }
}