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Why doesn't the file get deleted and renamed?

I have two models in my program, Bus and Learner.
Each is stored in a txt file, name Busses.txt and Learners.txt, respectively.
I am experiencing an issue where the method to delete a learner entry works, but the method to delete a bus entry does not, even though the code is practically identical.
Learner delete method:
public void deleteLearner(String ID) {
removeBlankLines("Learners.txt");
File oldFile = new File("Learners.txt");
File tempFile = new File("tempFile.txt");
String removeKey = ID;
String LearnerID;
String nameSurname;
boolean status;
String busOfLearner;
String line;
String lineToKeep;
try {
Scanner scFile = new Scanner(new File("Learners.txt"));
while (scFile.hasNext()) {
line = scFile.nextLine();
Scanner scLine = new Scanner(line).useDelimiter("#");
LearnerID = scLine.next();
nameSurname = scLine.next();
status = scLine.nextBoolean();
if (scLine.hasNext()) {
busOfLearner = scLine.next();
} else {
busOfLearner = "";
}
if (!LearnerID.equalsIgnoreCase(removeKey)) {
lineToKeep = LearnerID + "#" + nameSurname + "#" + status + "#" + busOfLearner + "\n";
FileWriter fWriter = new FileWriter(tempFile,true);
BufferedWriter bWriter = new BufferedWriter(fWriter);
bWriter.write(lineToKeep);
bWriter.close();
fWriter.close();
}
scLine.close();
}
scFile.close();
boolean successfulDelete = oldFile.delete();
File transfer = new File("Learners.txt");
boolean successfulRename = tempFile.renameTo(transfer);
}
catch (Exception e) {
System.out.println("An error has occured deleting a learner record " + e);
}
}
Delete bus method:
public void deleteBus(String removeBusName) {
removeBlankLinesBus("Busses.txt");
File oldFile = new File("Busses.txt");
File newFile = new File("NewBusFile.txt");
String deleteKey = removeBusName;
String currentBusName;
int currentNumSeats;
String currentPickLocation;
String currentDropLocation;
String currentPickTime;
String currentDropTime;
String line;
String lineToKeep;
try {
Scanner scFile = new Scanner(new File("Busses.txt"));
while (scFile.hasNext()) {
line = scFile.nextLine();
Scanner scLine = new Scanner(line).useDelimiter("#");
currentBusName = scLine.next();
currentNumSeats = scLine.nextInt();
currentPickLocation = scLine.next();
currentDropLocation = scLine.next();
currentPickTime = scLine.next();
currentDropTime = scLine.next();
if (!currentBusName.equalsIgnoreCase(deleteKey)) {
lineToKeep = currentBusName + "#" + currentNumSeats + "#" + currentPickLocation + "#" + currentDropLocation + "#" + currentPickTime + "#" + currentDropTime + "\n";
FileWriter fWriter = new FileWriter(newFile,true);
BufferedWriter bWriter = new BufferedWriter(fWriter);
bWriter.write(lineToKeep);
bWriter.close();
fWriter.close();
}
scLine.close();
}
scFile.close();
boolean successfulDelete = oldFile.delete();
File transfer = new File("Busses.txt");
boolean successfulRename = newFile.renameTo(transfer);
}
catch (Exception e) {
System.out.println("An error has occured deleting " + removeBusName + " from the file: " + e);
}
}
Problem:
With the delete bus method, the old file doesn't get deleted and the temporary or new file doesn't get renamed to the original file.
I am very confident that all files, streams, scanners, etc. are closed, as it is exactly the same as I did in the delete learner method, which does work and the files are deleted and renamed in the learner delete method as it should.
Assistance would be greatly appreciated.
EDIT: Implementation of methods:
Learner:
System.out.println(myController.PrintLearnerArr(myController.LoadLearner("Learners.txt")));
String delete = "0210045112055";
myController.deleteLearner(delete);
System.out.println(myController.PrintLearnerArr(myController.LoadLearner("Learners.txt")));
Bus:
System.out.println(myController.PrintBusArr(myController.LoadBus("Busses.txt")));
String deleteKey = "deleteme";
myController.deleteBus(deleteKey);
System.out.println(myController.PrintBusArr(myController.LoadBus("Busses.txt")));

How do I separate Big chunk of code of JDBC into different classes?

I wrote a big chunk of codes that downloads CSV file from url, then i bulk inserted into sql database, then call data from SQL server and display on Java console. Finally select the column I want to keep and export as a new CSV file.
but all of those codes are in the same class right now. How can I separate them into different class like I want a class for just download file and another class just do the Bulk insert and another class to just do the Select Query.
Thanks for helping me out
below is my code in one class now
public class ProjectTest extends CreateTable {
public static void main(String[] args) throws MalformedURLException {
BufferedReader br = null;
String line = "";
String cvsSplitBy = ",";
URL url = new URL(
"https://quality.data.gov.tw/dq_download_csv.php?nid=43983&md5_url=9d38afbca8243a24b5b89d03a8070aff");
try (InputStream inputStream = url.openStream();
FileOutputStream fos = new FileOutputStream(
"C:\\Users\\ALICE\\Desktop\\Java\\Dropbox\\Java\\virus.csv");
Connection connection = DriverManager
.getConnection("jdbc:sqlserver://localhost:1433;databaseName=JDBCDB", "andy3", "andy"); // andy3
// //
// ,andy
Statement stmt = connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
ResultSet.CONCUR_UPDATABLE);
FileOutputStream fos2 = new FileOutputStream(
"C:\\Users\\ALICE\\Desktop\\Java\\Dropbox\\Java\\NEWvirus.csv");
OutputStreamWriter osw = new OutputStreamWriter(fos2, "MS950");
BufferedWriter bw = new BufferedWriter(osw);
) {
byte[] buffer = new byte[1024];
int length;
while ((length = inputStream.read(buffer)) != -1) {
fos.write(buffer, 0, length);
}
fos.close();
stmt.executeUpdate("DROP TABLE Virus");
boolean rs = stmt.execute(CreateTable);
System.out.println("Database Created");
PreparedStatement pstmt = connection.prepareStatement(InsertData);
int executeUpdate = pstmt.executeUpdate();
if (executeUpdate > 0) {
System.out.println("Data Inserted");
} else {
System.out.println("Insert ERROR");
}
ResultSet rs4 = stmt.executeQuery("SELECT Count(*) FROM Virus");
int numberOfData = rs4.getInt(1);
System.out.println(numberOfData);
ResultSet rs3 = stmt.executeQuery(selectQuery);
ResultSetMetaData metaData = rs3.getMetaData();
DatabaseMetaData DmetaData = connection.getMetaData();
String[] types = { "TABLE" };
ResultSet rs5 = DmetaData.getTables(null, null, "Virus", types);
List<String> ColNameList = new ArrayList<String>();
while (rs5.next()) {
String tableName = rs5.getString("TABLE_NAME");
ResultSet columnRs = DmetaData.getColumns(null, null, tableName, null);
while (columnRs.next()) {
String columnName = columnRs.getString("COLUMN_NAME");
ColNameList.add(columnName);
}
System.out.print("|" + ColNameList.get(0) + " |");
System.out.print(ColNameList.get(1) + " |");
System.out.print(ColNameList.get(2) + "|");
System.out.print(ColNameList.get(3) + "|");
System.out.print(ColNameList.get(4) + "　|");
System.out.print(ColNameList.get(5) + "　|");
System.out.print(ColNameList.get(6) + "　 |");
System.out.print(ColNameList.get(7) + "　 |");
System.out.print(ColNameList.get(8) + "|");
System.out.print(ColNameList.get(9) + "　　　　 |");
System.out.print(ColNameList.get(10) + " |");
System.out.print(ColNameList.get(11) + "|");
System.out.print(ColNameList.get(12) + " |");
System.out.print(ColNameList.get(13) + " |");
System.out.print(ColNameList.get(14) + " |");
System.out.print(ColNameList.get(15) + "");
}
System.out.println();
while (rs3.next()) {
coList1.add(rs3.getString(1));
coList2.add(rs3.getString(2));
coList3.add(rs3.getString(3));
coList4.add(rs3.getString(4));
coList5.add(rs3.getString(5));
coList6.add(rs3.getString(6));
coList7.add(rs3.getString(7));
coList8.add(rs3.getString(8));
coList9.add(rs3.getString(9));
coList10.add(rs3.getString(10));
coList11.add(rs3.getString(11));
coList12.add(rs3.getString(12));
coList13.add(rs3.getString(13));
coList14.add(rs3.getString(14));
coList15.add(rs3.getString(15));
coList16.add(rs3.getString(16));
coList17.add(rs3.getString(17));
}
for (int p = 0; p < 20; p++) { // coList9.size(
System.out.print("|" + coList1.get(p) + "|");
String str2 = coList2.get(p);
if (str2.length() < 3) {
String blank = "　";
String repeated = new String(new char[(3 - str2.length())]).replace("\0", blank);
System.out.print(repeated + coList2.get(p) + "|");
} else {
System.out.print(coList2.get(p) + "|");
}
System.out.print("　" + coList3.get(p) + "|");
System.out.print(coList4.get(p) + "|");
System.out.print(coList5.get(p) + "|");
System.out.print(coList6.get(p) + "|");
System.out.print(coList7.get(p) + "|");
System.out.print(coList8.get(p) + "|");
String str = coList9.get(p);
if (str.length() < 5) {
String blank = "　";
String repeated = new String(new char[(5 - str.length())]).replace("\0", blank);
System.out.print(repeated + coList9.get(p) + "|");
} else {
System.out.print(coList9.get(p) + "|");
}
System.out.print(coList10.get(p) + "|");
System.out.print(coList11.get(p) + "|");
String str12 = coList12.get(p);
if (str12.length() < 5) {
String blank = " ";
String repeated = new String(new char[(6 - str12.length())]).replace("\0", blank);
System.out.print(repeated + coList12.get(p) + "|");
} else {
System.out.print(coList12.get(p) + "|");
}
String str13 = coList13.get(p);
if (str13.length() < 5) {
String blank = " ";
String repeated = new String(new char[(4 - str13.length())]).replace("\0", blank);
System.out.print(repeated + coList13.get(p) + "|");
} else {
System.out.print(coList12.get(p) + "|");
}
System.out.print(coList14.get(p) + "|");
System.out.print(coList15.get(p) + "|");
System.out.print(coList16.get(p) + "|");
System.out.print(coList17.get(p) + "|");
System.out.println();
}
rs3.beforeFirst();
StringBuilder builder = new StringBuilder();
builder.append("CaseID").append(",").append("Age").append(",").append("Gender").append(",").append("City")
.append(",").append("SampleDate").append(",").append("VirusType").append(",")
.append("SubType").append(",").append("Locus").append(",").append("Primer").append(",").append("GeneDirection")
.append(",").append("TypingMethod").append(",").append("DNASeq").append(",").append("AminoAcidSeq");
System.out.println(rs3.next());
while (rs3.next()) {
builder.append(System.lineSeparator());
builder.append(rs3.getString(1)).append(",").append(rs3.getString(2)).append(",")
.append(rs3.getString(3)).append(",").append(rs3.getString(5)).append(",")
.append(rs3.getString(7)).append(",").append(rs3.getString(10)).append(",")
.append(rs3.getString(11)).append(",").append(rs3.getString(12)).append(",")
.append(rs3.getString(13)).append(",").append(rs3.getString(14)).append(",")
.append(rs3.getString(15)).append(",").append(rs3.getString(16)).append(",").append(rs3.getString(17)).append(",");
}
bw.write(builder.toString());
} catch (IOException e) {
e.printStackTrace();
} catch (SQLException e1) {
e1.printStackTrace();
}
}
}

Start refactoring your code in small steps and then iteratively improve your design if needed.
As you have mentioned the algorithmic approach, leveraging that this should be your starting step.
CSV file from url,
then i bulk inserted into sql database,
then call data from SQL server and
display on Java console.
Finally select the column I want to keep
and export as a new CSV file.
Small helper functions for each of these steps.
Read more about SOLID design principles if that helps in improving your solution.

Can't access a variable declared in an interface even though it's implemented in another class

I have a interface called StringInput with the following code.
public static ArrayList<String[]> fileInput() throws IOException {
ArrayList<String[]> lines = new ArrayList<>();
try (BufferedReader br = new BufferedReader(new FileReader(file))) {
String line;
while ((line = br.readLine()) != null) {
String[] formatted = format(line);
lines.add(formatted);
System.out.println(line);
}
}
return lines;
}
public static String[] format(String s) {
String[] data = new String[9];
String logEntryPattern = "^([\\d.]+) (\\S+) (\\S+) \\[([\\w:/]+\\s[+\\-]\\d{4})\\] \"(.+?)\" (\\d{3}) (\\d+) \"([^\"]+)\" \"([^\"]+)\"";
System.out.println("Using RE Pattern:");
System.out.println(logEntryPattern);
System.out.println("Combined Apache Log Format (VERBOSE)");
System.out.println("Input line is:");
System.out.println(s);
Pattern p = Pattern.compile(logEntryPattern);
Matcher matcher = p.matcher(s);
if (!matcher.matches()
|| NUM_FIELDS != matcher.groupCount()) {
System.err.println("Bad log entry (or problem with RE?):");
System.err.println(s);
return null;
}
System.out.println("IP Address: " + matcher.group(1));
String clientIP = matcher.group(1);
System.out.println("Identd: " + matcher.group(2));
String identd = matcher.group(2);
System.out.println("UserID: " + matcher.group(3));
String userID = matcher.group(3);
System.out.println("Date&Time: " + matcher.group(4));
String dateTime = matcher.group(4);
System.out.println("Request: " + matcher.group(5));
String protocol = matcher.group(5);
System.out.println("Response: " + matcher.group(6));
String respCode = matcher.group(6);
System.out.println("Bytes Sent: " + matcher.group(7));
String respSize = matcher.group(7);
System.out.println("Referer: " + matcher.group(8));
String refer = matcher.group(8);
System.out.println("Browser: " + matcher.group(9));
String userAgent = matcher.group(9);
data[0] = clientIP;
data[1] = identd;
data[2] = userID;
data[3] = dateTime;
data[4] = protocol;
data[5] = respCode;
data[6] = respSize;
data[7] = refer;
data[8] = userAgent;
return data;
}
and another class called ParseUpload which implements the interface and contains a main method. Inside the main method I have a prepared statement trying to call a variable from the interface. However, I can't. I have no idea and since I don't usually work with interfaces, not instantiating it is weird for me.
Any help? Thanks.
EDIT: This is the other class.
public class ParseUpload implements StringInput {
public static void main(String argv[]) {
try {
StringInput.fileInput();
} catch (Exception e) {
e.printStackTrace();
}
//while (logEntryLine !=null){
// for (int i = 0; i < file.length(); i++){
//System.out.println(fileExists); ignore/For testing purposes
Connection conn = null;
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:5294/mysql", "root", "Iu&#KR489)(");
System.out.println("Database Connection Established!");
String query = " insert into alogs(clientIP, identd, userID, dateTime, protocol, respCode, respSize, refer, userAgent)"
+ " values (?, ?, ?, ? ,? ,? ,?, ?, ?)";
PreparedStatement preparedStmt = con.prepareStatement(query);
preparedStmt.setString(1, data);
preparedStmt.setString(2, identd);
preparedStmt.setString(3, userID);
preparedStmt.setString(4, dateTime);
preparedStmt.setString(5, protocol);
preparedStmt.setString(6, respCode);
preparedStmt.setString(7, respSize);
preparedStmt.setString(8, refer);
preparedStmt.setString(9, userAgent);
preparedStmt.execute();
con.close();
} catch (SQLException ex) {
System.out.println("****************************Can't Connect to the database***********************************");
System.out.println("SQLException: " + ex.getMessage());
System.out.println("SQLState: " + ex.getSQLState());
System.out.println("VendorError: " + ex.getErrorCode());
} catch (ClassNotFoundException e) {
System.out.println("Class Not Found");
}
// }
}
}

Your problem isn't an interface problem.
In your case you should have :
StringInput as a class with some statics methods (these methods will return a variable and you'll be able to use it)
ParseUpload calling these methods in order to get a result and use it.
Here is a short example :
public class StringInput {
public static String[] format() {
String[] datas = new String[2];
datas[0] = "Some";
datas[1] = "thing";
return datas;
}
}
And :
public class ParseUpload {
public static void main(String[] args) {
String[] resultOfFormatCall = StringInput.format();
// Now you have the result of your format method, and you are able to use it
System.out.println("result[0]" + resultOfFormatCall[0] + ";result[1]" + resultOfFormatCall[1]);
}
}

Text not being written to file

I cannot seem to figure this out. In the method below I'm trying to write a boolean to a file in 2 places, however nothing is actually being written. Any help would be greatly appreciated.
private void renameTables(){
String path = MessengerMain.getInstance().getDataFolder() + File.separator + "v3-0-0 Table Rename.txt";
File f = new File(path);
try(ResultSet rs = conn.getMetaData().getTables(null, null, "%", null); Writer w = new PrintWriter(new FileOutputStream(f, false))){
if (!f.exists()){
f.createNewFile();
w.write("false");
w.flush();
}
List<String> lines = Files.readAllLines(Paths.get(path));
if (lines.get(0).equalsIgnoreCase("false")){
System.out.println("[Messenger] Verifying table names...");
int count = 0;
List<String> tables = new ArrayList<String>();
tables.add("messages");
tables.add("scores");
tables.add("contacts");
while (rs.next()){
String table = rs.getString("TABLE_NAME");
if (tables.contains(table)){
update("ALTER TABLE " + table + " RENAME TO " + ("messenger_" + table) + ";");
count++;
}
}
if (count > 0){
System.out.println("[Messenger] Done. " + count + " table" + (count == 1 ? "" : "s") + " renamed.");
}else{
System.out.println("[Messenger] Done. No tables need to be renamed.");
}
w.write("true");
w.flush();
}
} catch (SQLException | IOException e){
e.printStackTrace();
}
}
Following Elliot Frisch's advice (same results):
private void renameTables(){
String path = MessengerMain.getInstance().getDataFolder() + File.separator + "v3-0-0 Table Rename.txt";
File f = new File(path);
try(ResultSet rs = conn.getMetaData().getTables(null, null, "%", null)){
Writer w = new PrintWriter(new FileOutputStream(f, false));
if (!f.exists()){
f.createNewFile();
w.write("false");
w.close(); //close here
}
List<String> lines = Files.readAllLines(Paths.get(path));
if (lines.get(0).equalsIgnoreCase("false")){
System.out.println("[Messenger] Verifying table names...");
int count = 0;
List<String> tables = new ArrayList<String>();
tables.add("messages");
tables.add("scores");
tables.add("contacts");
while (rs.next()){
String table = rs.getString("TABLE_NAME");
if (tables.contains(table)){
update("ALTER TABLE " + table + " RENAME TO " + ("messenger_" + table) + ";");
count++;
}
}
if (count > 0){
System.out.println("[Messenger] Done. " + count + " table" + (count == 1 ? "" : "s") + " renamed.");
}else{
System.out.println("[Messenger] Done. No tables need to be renamed.");
}
w = new PrintWriter(new FileOutputStream(f, false)); //create a new writer
w.write("true");
w.close(); //close here
}
} catch (SQLException | IOException e){
e.printStackTrace();
}
}

Here is a working full minimal, complete, verifiable example
public static void main(String[] args) {
File f = new File(System.getProperty("user.home"), "temp.txt");
String path = f.getPath();
try (Writer w = new FileWriter(f)) {
w.write("false");
} catch (IOException e) {
e.printStackTrace();
}
try {
List<String> lines = Files.readAllLines(Paths.get(path));
System.out.println(lines);
} catch (IOException e) {
e.printStackTrace();
}
}
Output is (as expected)
[false]

How to find closer maven repository close to my home

I am wondering how to find the maven repository close to my home?

Actually, the listing at http://docs.codehaus.org/display/MAVENUSER/Mirrors+Repositories is problematic. Is Central in San Francisco, California or in St. Louis, Missouri? (I guess this is an inadvertent lesson on why code, or even xml, should not be commented). To make things more confusing, the owner of the domain (according to http://whois.net/whois/maven.org) is in Fulton, MD.
Maybe the question was not "Where are the repositories?" (which esaj answered), but really:
"How can I find the maven repository closest to my home?"
That question bugged me, too.
On the other hand, does it really matter, given how fast packets travel across the world?
But it still bugged me.
There are two ways to find out which host is the closest:
Open a browser, go to http://freegeoip.net, and type in the hostname. If you know where you are, then you can go to GoogleMaps, get directions, and check the distance.
Open a terminal window, and ping the hostname to find the average round trip transit time in milliseconds. This will give you the electronic distance, which is really more important for file transfer times.
Repeat for each hostname (i.e. about 40 times, if you're looking at the download sites for Maven itself)
Sort by the distance measured by the GoogleMaps directions, or by the transit time.
For 40 hosts you could probably do that manually in 20 tedious minutes, but a true professional would rather spend a few hours writing the Selenium and java code that could do it in 5 minutes.
In my copious amounts of spare time, I threw together only half the job (i.e. no Selenium):
public class ClosestUrlFinder {
/**
* Find out where a hostname is.
* Adapted from http://www.mkyong.com/java/how-to-send-http-request-getpost-in-java/
* Send HTTP GET requests to: freegeoip.net/{format}/{ip_or_hostname}
* The API supports both HTTP and HTTPS.
* Supported formats are csv, xml or json.
* E.G. http://freegeoip.net/xml/www.poolsaboveground.com
* returns <Response><Ip>207.58.184.93</Ip><CountryCode>US</CountryCode>
* <CountryName>United States</CountryName><RegionCode>VA</RegionCode><RegionName>Virginia</RegionName>
* <City>Mclean</City><ZipCode>22101</ZipCode>
* <Latitude>38.9358</Latitude><Longitude>-77.1621</Longitude>
* <MetroCode>511</MetroCode><AreaCode>703</AreaCode></Response>
* #param urlOrHostname
* #return
*/
public String getUrlLocation(String urlOrHostname) {
String USER_AGENT = "Mozilla/5.0";
BufferedReader in = null;
URL urlObject;
StringBuilder response = null;
try {
urlObject = new URL("http://freegeoip.net/xml/" + urlOrHostname);
HttpURLConnection connection = (HttpURLConnection) urlObject.openConnection();
connection.setRequestMethod("GET");
connection.setRequestProperty("User-Agent", USER_AGENT);
int responseCode = connection.getResponseCode();
System.out.println("\nSending 'GET' request to URL : " + urlOrHostname);
System.out.println("Response Code : " + responseCode);
in = new BufferedReader( new InputStreamReader(connection.getInputStream()));
String inputLine;
response = new StringBuilder();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (in != null) {
try { in.close(); }
catch (IOException e) {
e.printStackTrace();
}
}
}
//System.out.println(response.toString());
return response.toString();
}
/*
* Fixed version of code from http://stackoverflow.com/questions/11506321/java-code-to-ping-an-ip-address
*/
public String runDosCommand(List<String> command)
{
String string = "", result = "";
ProcessBuilder pBuilder = new ProcessBuilder(command);
Process process;
try {
process = pBuilder.start();
BufferedReader stdInput = new BufferedReader(new InputStreamReader(process.getInputStream()));
BufferedReader stdError = new BufferedReader(new InputStreamReader(process.getErrorStream()));
//System.out.println("Standard output of the command:");
while ((string = stdInput.readLine()) != null)
{
System.out.println(string);
result = result + "\n" + string;
}
while ((string = stdError.readLine()) != null)
{
System.out.println("stdError: "+ string);
result = result + "\nstdError: " + string;
}
} catch (IOException e) {
System.out.println("Error with command "+command);
e.printStackTrace();
}
return result;
}
public String pingUrl(String url) {
List<String> command = new ArrayList<String>();
String averagePingTime = "0", geoText = "", loss = "";
command.add("ping");
command.add("-n");
command.add("2");
url = url.replace("ftp://", "");
url = Utils.first(url.replace("/", " "));
url = Utils.first(url.replace(":", " "));
command.add(url);
System.out.println("command is: "+command);
String pingResult = runDosCommand(command);
String timeoutString = "Request timed out";
String timeout = Utils.grep(timeoutString, pingResult);
String noHostString = "Ping request could not find host";
String noHost = Utils.grep(noHostString, pingResult);
String unreachableString = "Destination net unreachable";
String unreachable = Utils.grep(unreachableString, pingResult);
if (Utils.isNullOrEmptyString(timeout) && Utils.isNullOrEmptyString(noHost)
&& Utils.isNullOrEmptyString(unreachable)) {
String lostString = "Lost =";
loss = Utils.grep(lostString, pingResult);
int index = loss.indexOf(lostString);
loss = loss.substring(index);
if (!loss.equals("Lost = 0 (0% loss),")) {
System.out.println("Non-zero loss for " + url);
averagePingTime = "0";
} else {
String replyString = "Reply from";
String replyFrom = Utils.grep(replyString, pingResult);
String ipAddress = Utils.nth(replyFrom, 3);
System.out.println("reply Ip="+ipAddress.replace(":", ""));
String averageString = "Average =";
averagePingTime = Utils.grep(averageString, pingResult);
index = averagePingTime.indexOf(averageString);
averagePingTime = averagePingTime.substring(index);
averagePingTime = Utils.last(averagePingTime).replace("ms", "");
String xml = getUrlLocation(url);
//System.out.println("xml="+xml);
geoText = extractTextFromXML(xml);
System.out.println("geoText="+geoText);
}
} else {
averagePingTime = "0";
System.out.println("Error. Either could not find host, Request timed out, or unreachable network for " + url);;
}
System.out.println("Results for " + url + " are: " + loss + " " + averagePingTime + " miliseconds.");
return url + " " + averagePingTime + " " + geoText ;
}
public ArrayList<Entry<String,Integer>> pingManyUrls() {
ArrayList<Entry<String,Integer>> mirrorTimeList = new ArrayList<>();
String[] urls = Utils.readTextFile("resources/MavenUrls.txt").split("\\s+");
System.out.println("Start pingManyUrls with "+urls.length + " urls.");
for (String url : urls) {
url = url.trim();
System.out.println("************************************\npingManyUrls: Check Url " + url);
if (arrayListContainsKey(url, mirrorTimeList)) {
System.out.println("Key " + url + " already in array.");
} else {
String pingInfo = pingUrl(url);
String averagePingString = Utils.nth(pingInfo, 2);
if (!averagePingString.equals("0")) {
int averagePingMilliseconds = Integer.parseInt(averagePingString);
pingInfo = Utils.rest(pingInfo); //chop the first term (the url)
pingInfo = Utils.rest(pingInfo); // chop the 2nd term (the time)
url = url + " " + pingInfo;
System.out.println(" Adding Key " + url + " " + averagePingMilliseconds + " to array.");
Entry<String,Integer> urlTimePair = new java.util.AbstractMap.SimpleEntry<>(url, averagePingMilliseconds);
mirrorTimeList.add(urlTimePair);
} else { System.out.println("Url " + url + " has a problem and therefore will be not be included."); }
}
}
Collections.sort(mirrorTimeList, new Comparator<Entry<String,Integer>>() {
#Override
public int compare (Entry<String,Integer> pair1, Entry<String,Integer> pair2) {
return pair1.getValue().compareTo(pair2.getValue());
}
});
return mirrorTimeList;
}
public boolean arrayListContainsKey(String key, ArrayList<Entry<String,Integer>> arrayList) {
for (Entry<String,Integer> keyValuePair : arrayList) {
//System.out.println(keyValuePair.getKey() + " =? " + key);
if (key.equalsIgnoreCase(keyValuePair.getKey())) { return true; }
}
return false;
}
public String extractFirstTagContents(Element parentElement, String tagname) {
NodeList list = parentElement.getElementsByTagName(tagname);
if (list != null && list.getLength()>0) {
String contents = list.item(0).getTextContent();
System.out.println("Tagname=" + tagname + " contents="+contents);
return contents;
}
return "";
}
public String extractTextFromXML(String xml) {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder;
String content = "";
try {
builder = factory.newDocumentBuilder();
Document document = builder.parse(new InputSource(new StringReader(xml)));
Element rootElement = document.getDocumentElement();
content = rootElement.getTextContent();
//System.out.println("content="+content);
// String city = extractFirstTagContents(rootElement, "City");
// String state = extractFirstTagContents(rootElement, "RegionName");
// String zipCode = extractFirstTagContents(rootElement, "ZipCode");
// String country = extractFirstTagContents(rootElement, "CountryName");
// String latitude = extractFirstTagContents(rootElement, "Latitude");
// String longitude = extractFirstTagContents(rootElement, "Longitude");
} catch (ParserConfigurationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SAXException saxex) {
// TODO Auto-generated catch block
saxex.printStackTrace();
} catch (IOException ioex) {
// TODO Auto-generated catch block
ioex.printStackTrace();
}
return content;
}
public static void main(String[] args) {
System.out.println("Starting ClosestUrlFinder");
ClosestUrlFinder ping = new ClosestUrlFinder();
ArrayList<Entry<String,Integer>> mirrorList = ping.pingManyUrls();
System.out.println("Final Results, sorted by trip travel time (out of "+mirrorList.size()+" successful pings).");
for (Entry<String,Integer> urlTime : mirrorList) {
System.out.println(urlTime.getKey() + " " + urlTime.getValue());
}
}
} // End of Class
Where the data in MavenUrls.txt is:
apache.claz.org
apache.cs.utah.edu
apache.mesi.com.ar
apache.mirrors.hoobly.com
apache.mirrors.lucidnetworks.net
apache.mirrors.pair.com
apache.mirrors.tds.net
apache.osuosl.org
apache.petsads.us
apache.spinellicreations.com
apache.tradebit.com
download.nextag.com
ftp.osuosl.org
ftp://mirror.reverse.net/pub/apache/
mirror.cc.columbia.edu/pub/software/apache/
mirror.cogentco.com/pub/apache/
mirror.metrocast.net/apache/
mirror.nexcess.net/apache/
mirror.olnevhost.net/pub/apache/
mirror.reverse.net/pub/apache/
mirror.sdunix.com/apache/
mirror.symnds.com/software/Apache/
mirror.tcpdiag.net/apache/
mirrors.gigenet.com/apache/
mirrors.ibiblio.org/apache/
mirrors.sonic.net/apache/
psg.mtu.edu/pub/apache/
supergsego.com/apache/
www.bizdirusa.com
www.bizdirusa.com/mirrors/apache/
www.carfab.com/apachesoftware/
www.dsgnwrld.com/am/
www.eng.lsu.edu/mirrors/apache/
www.gtlib.gatech.edu/pub/apache/
www.interior-dsgn.com/apache/
www.motorlogy.com/apache/
www.picotopia.org/apache/
www.poolsaboveground.com/apache/
www.trieuvan.com/apache/
www.webhostingjams.com/mirror/apache/
And my Utils class includes the following:
/**
* Given a string of words separated by spaces, returns the first word.
* #param string
* #return
*/
public static String first(String string) {
if (isNullOrEmptyString(string)) { return ""; }
string = string.trim();
int index = string.indexOf(" "); //TODO: shouldn't this be "\\s+" to handle double spaces and tabs? That means regexp version of indexOf
if (index<0) { return string; }
return string.substring(0, index);
}
/**
* Given a string of words separated by spaces, returns the rest of the string after the first word.
* #param string
* #return
*/
public static String rest(String string) {
if (isNullOrEmptyString(string)) { return ""; }
string = string.trim();
int index = string.indexOf(" "); //TODO: shouldn't this be "\\s+" to handle double spaces and tabs? That means regexp version of indexOf
if (index<0) { return ""; }
return string.substring(index+1);
}
public static String grep(String regexp, String multiLineStringToSearch) {
String result = "";
//System.out.println("grep for '"+ regexp + "'");
String[] lines = multiLineStringToSearch.split("\\n");
//System.out.println("grep input string contains "+ lines.length + " lines.");
Pattern pattern = Pattern.compile(regexp);
for (String line : lines) {
Matcher matcher = pattern.matcher(line);
if (matcher.find()) {
//System.out.println("grep found match="+ line);
result = result + "\n" + line;
}
}
return result.trim();
}
/**
* Given the path and name of a plain text (ascii) file,
* reads it and returns the contents as a string.
* #param filePath
* #return
*/
public static String readTextFile(String filePath) {
BufferedReader reader;
String result = "";
int counter = 0;
try {
reader = new BufferedReader(new FileReader(filePath));
String line = "";
StringBuilder stringBuilder = new StringBuilder();
String lineSeparator = System.getProperty("line.separator");
while ((line = reader.readLine()) != null) {
counter = counter + 1;
stringBuilder.append(line);
stringBuilder.append(lineSeparator);
}
reader.close();
result = stringBuilder.toString();
logger.info("readTextFile: Read "+filePath+" with "+ counter + " lines, "+result.length()+" characters.");
return result;
} catch (FileNotFoundException e) {
logger.fatal("readTextFile: Could not find file "+filePath+".");
e.printStackTrace();
} catch (IOException e) {
logger.fatal("readTextFile: Could not read file "+filePath+".");
e.printStackTrace();
}
return "";
}
public static boolean isNullOrEmptyString(String s) {
return (s==null || s.equals(""));
}
/**
* Given a string of words separated by one or more whitespaces, returns the Nth word.
* #param string
* #return
*/
public static String nth(String string, int n) {
string = string.trim();
String[] splitstring = string.split("\\s+");
String result = "";
if (splitstring.length<n) { return ""; }
else {
result = splitstring[n - 1];
}
return result.trim();
}
/**
* Given a string of words separated by spaces, returns the last word.
* #param string
* #return
*/
public static String last(String string) {
return string.substring(string.trim().lastIndexOf(" ")+1, string.trim().length());
}
Enjoy!

Here's there official central repository mirror listing (as xml-file) and here's another list of central repository mirrors.