[Demonstration 1]

[Buggy Method]
private void gen_configfile() {
    FileWriter fw = null;
    BufferedWriter bw = null;
    try {
        File f = new File("cliquecon.cfg");
        fw = new FileWriter(f);
        bw = new BufferedWriter(fw);
        bw.write("cliquefile=" + this.clique_base_filename + "\n");
        bw.write("maxclosure=" + String.valueOf(this.k_closure) + "\n");
        bw.write("graphfile=" + graph_base_filename + "\n");
        bw.write("outputdir=" + fullpath_output);
    } catch (IOException ex) {
        Logger.getLogger(Iterative_trans_closure_forpython.class.getName()).log(Level.SEVERE, null, ex);
    } finally {
        try {
            bw.close();
        } catch (IOException ex) {
            Logger.getLogger(Iterative_trans_closure_forpython.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

[Buggy Hunk]
bw.write("maxclosure=" + String.valueOf(this.k_closure) + "\n");

[Patch]
bw.write("maxclosure=" + String.valueOf(this.maxclique) + "\n");

[Demonstration 2]

[Buggy Method]
@EventHandler(priority = EventPriority.LOWEST)
public void onCmd(PlayerCommandPreprocessEvent e) {
    String command = e.getMessage().toLowerCase();
    List<String> blockedCmds = wild.getConfig().getStringList("BlockCommands");
    if (TeleportTarget.cmdUsed.contains(e.getPlayer().getUniqueId())) {
        for (String cmd : blockedCmds) {
            if (command.contains(cmd))
                ;
            {
                e.getPlayer().sendMessage(ChatColor.translateAlternateColorCodes('&', wild.getConfig().getString("Blocked_Command_Message")));
                e.setCancelled(true);
                break;
            }
        }
    } else if (e.getMessage().equalsIgnoreCase("wild") && wild.getConfig().getBoolean("FBasics")) {
        e.setCancelled(true);
        CheckPerms check = new CheckPerms(wild);
        Checks checks = new Checks(wild);
        Player p = e.getPlayer();
        if (!checks.world(p))
            p.sendMessage(ChatColor.translateAlternateColorCodes('&', wild.getConfig().getString("WorldMsg")));
        else
            check.check(p);
    }
}

[Buggy Hunk]
if (command.contains(cmd)) ;

[Patch]
if (command.contains(cmd))

[Demonstration 3]

[Buggy Method]
@Override
public void print(PrintWriter writer, String tabs) throws IOException {
    writer.write(tabs + "=\n");
    writer.write(tabs + "    " + id + "\n");
    value.print(writer, "    " + tabs);
}

[Buggy Hunk]
writer.write(tabs+"    "+id+"\n");

[Patch]
id.print(writer, tabs);