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Parse a semicolon separated file in Java

I have a excel file and the contents are shown below.
First line is header, second line on wards is the data.
Cell A1 contains line below (Header)
**IsShooting; Velocity; Location_x; Location_y; Location_z; Onslaught_ONSAV ; ***Event***; EventParams...**
Cell A2 contains below
0;0;0;0;0;0;0;0;0;0;0.000;0.000;0;0.000;0.000;None;0;0;0.000;-1983.610;-
Cell A3 Contains below
;0.250;0.000;0.000;0.000;0.000;***BOT_KILLED***;CTF-Geothermal.GBxBot10;XWeapons.DamTypeFlakChunk
Cell A4 Contains below
4.110;161.900;0.000;0.000;0.000;0.000;0.000;0.000;0.000;0.000;0.000;0.000;0.000;0.000;0.000;4.320;0.000;0.260;0.000;0.000;***FLAG_PICKEDUP***;0;CTF-Geothermal.GBxBot10
I want to know if there are any open Source CSV Parsers, I can use so that, I can get the data from the excel.
The above excel file contains 400 lines of data. All I want from this is the COUNT of FLAG_PICKEDUP & BOT_KILLED.
Thanks!

This is the easiest way I can think of. Use a BufferedReader to read each line. For each line split it into a String array, then check each String to see if it equals the constants that define flag pickups or bot kills.
I think Apache makes csv parser, but I've never used it. For something this simple it might just be easier to code it yourself. This is what I came up with in about 5 mins.
NOTE: All due respect, stackoverflow generally asks that you attempt to solve the problem yourself first. Since you didn't post code, we can't help you debug and we don't know if you tried to solve the problem yourself. This was simple, so I helped but you may find it easier to get support if you post your (failed) solution first.
public static void main(String[] args) throws Exception
{
int botKilledCount = 0, flagPickedUpCount = 0;
String line, botLiteral = "***BOT_KILLED***", flagLiteral = "***FLAG_PICKEDUP***";
BufferedReader reader = new BufferedReader(new FileReader(new File("!!YOUR FILE HERE!!")));
while ((line = reader.readLine()) != null)
for (String s : line.split(";"))
if (s.equals(botLiteral))
botKilledCount++;
else if (s.equals(flagLiteral))
flagPickedUpCount++;
System.out.println("Bot Killed Count: " + botKilledCount + ", Flag Pickup Count: " + flagPickedUpCount);
}
This was the output:
Bot Killed Count: 1, Flag Pickup Count: 1

Read the five score in a textfile then print them back with the new score added to the list - ANDROID

In my program when the player submits a score it gets added to a local text file called localHighScores. This is list of the top five score the player has achieved while on that specific device.
I wasn't sure how to write to a new line using FileOutputStream (if you know please share), so instead I've inputted a space in between each score. Therefore what I am trying to do is when the player clicks submit the program will open the file and read any current data is saved. It will save it to an String Array, each element being one of the five score in the text file and when it hits a 'space' in the fie it will add the score just read to the write array element
The code I currently have is as follows:
String space = " ";
String currentScoreSaved;
String[] score = new String[5];
int i = 0;
try
{
BufferedReader inputReader = new BufferedReader(new InputStreamReader(openFileInput("localHighScore.txt")));
String inputString;StringBuffer stringBuffer = new StringBuffer();
while ((inputString = inputReader.readLine()) != null && i < 6)
{
if((inputString = inputReader.readLine()) != space)
{
stringBuffer.append(inputString + "\n");
i++;
score[i] = stringBuffer.toString();
}
}
currentScoreSaved = stringBuffer.toString();
FileOutputStream fos = openFileOutput("localHighScore.txt", Context.MODE_PRIVATE);
while (i < 6)
{
i++;
fos.write(score[i].getBytes());
fos.write(space.getBytes());
}
fos.write(localHighScore.getBytes());
//fos.newLine(); //I thought this was how you did a new line but sadly I was mistaken
fos.close();
}
catch(Exception e)
{
e.printStackTrace();
}
Now you will notice this doesn't re arrange the score if a new highscore is achieved. That I am planning on doing next. For the moment I am just trying to get the program to do the main thing which is read in the current data, stick it in an Array then print it back to that file along with the new score
Any Ideas how this might work, as currently it's printing out nothing even when I had score in the textfile before hand

I'm only a first year student in Java programming and I am a new user here at stackoverflow.com, so pardon me if coding for android has some special rules I don't know about, which prevents this simple and humble example from working. But here is how I would read from a file in the simplest of ways.
File tempFile = new File("<SubdirectoryIfAny/name_of_file.txt");
Scanner readFile = new Scanner( tempFile );
// Assuming that you can structure the file as you please with fx each bit of info
// on a new line.
int counter = 0;
while ( readFile.hasNextLine() ) {
score[counter] = readFile.nextLine();
counter++;
}
As for the writing back to the file? Put it in an entirely different method and simply make a simplified toString-like method, that prints out all the values the exact way you want them in the file, then create a "loadToFile" like method and use the to string method to print back into the file with a printstream, something like below.
File tempFile = new File("<SubdirectoryIfAny/name_of_file.txt");
PrintStream write = new PrintStream(tempFile);
// specify code for your particular program so that the toString method gets the
// info from the string array or something like that.
write.print( <objectName/this>.toStringLikeMethod() );
// remember the /n /n in the toStringLikeMethod so it prints properly in the file.
Again if this is something you already know, which is just not possible in this context please ignore me, but if not I hope it was useful. As for the exceptions, you can figure that you yourself. ;)

Since you are a beginner, and I assume you are trying to get things off the ground as quickly as possible, I'd recommend using SharedPreferences. Basically it is just a huge persistent map for you to use! Having said that... you should really learn about all the ways of storage in Android, so check out this document:
http://developer.android.com/guide/topics/data/data-storage.html
The Android docs are awesome! FYI SharedPreferences may not be the best and awesomest way to do this... but I'm all for quick prototyping as a learner. If you want, write a wrapper class around SharedPreferences.

Textscreen in Codename One, how to read text file?

I want to add a help screen to my Codename One App.
As the text is longer as other strings, I would like put it in a separate file and add it to the app-package.
How do I do this? Where do I put the text file, and how can I easily read it in one go into a string?
(I already know how to put the string into a text area inside a form)

In the Codename One Designer go to the data section and add a file.
You can just add the text there and fetch it using myResFile.getData("name");.
You can also store the file within the src directory and get it using Display.getInstance().getResourceAsStream("/filename.txt");

I prefer to have the text file in the filesystem instead of the resource editor, because I can just edit the text with the IDE. The method getResourceAsStream is the first part of the solution. The second part is to load the text in one go. There was no support for this in J2ME, you needed to read, handle buffers etc. yourself. Fortunately there is a utility method in codename one. So my working method now looks like this:
final String HelpTextFile = "/helptext.txt";
...
InputStream in = Display.getInstance().getResourceAsStream(
Form.class, HelpTextFile);
if (in != null){
try {
text = com.codename1.io.Util.readToString(in);
in.close();
} catch (IOException ex) {
System.out.println(ex);
text = "Read Error";
}
}

The following code worked for me.
//Gets a file system storage instance
FileSystemStorage inst = FileSystemStorage.getInstance();
//Gets CN1 home`
final String homePath = inst.getAppHomePath();
final char sep = inst.getFileSystemSeparator();
// Getting input stream of the file
InputStream is = inst.openInputStream(homePath + sep + "MyText.txt");
// CN1 Util class, readInputStream() returns byte array
byte[] b = Util.readInputStream(is);
String myString = new String(b);

How to escape comma and double quote at same time for CSV file?

I am writing a Java app to export data from Oracle to csv file
Unfortunately the content of data may quite tricky. Still comma is the deliminator, but some data on a row could be like this:
| ID | FN | LN | AGE | COMMENT |
|----------------------------------------------------------------|
| 123 | John | Smith | 39 | I said "Hey, I am 5'10"." |
|----------------------------------------------------------------|
so this is one of the string on the comment column:
I said "Hey, I am 5'10"."
No kidding, I need to show above comment without compromise in excel or open office from a CSV file generated by Java, and of course cannot mess up other regular escaping situation(i.e. regular double quotes, and regular comma within a tuple). I know regular expression is powerful but how can we achieve the goal with such complicated situation?

There are several libraries. Here are two examples:
❐ Apache Commons Lang
Apache Commons Lang includes a special class to escape or unescape strings (CSV, EcmaScript, HTML, Java, Json, XML): org.apache.commons.lang3.StringEscapeUtils.
Escape to CSV
String escaped = StringEscapeUtils
.escapeCsv("I said \"Hey, I am 5'10\".\""); // I said "Hey, I am 5'10"."
System.out.println(escaped); // "I said ""Hey, I am 5'10""."""
Unescape from CSV
String unescaped = StringEscapeUtils
.unescapeCsv("\"I said \"\"Hey, I am 5'10\"\".\"\"\""); // "I said ""Hey, I am 5'10""."""
System.out.println(unescaped); // I said "Hey, I am 5'10"."
* You can download it from here.
❐ OpenCSV
If you use OpenCSV, you will not need to worry about escape or unescape, only for write or read the content.
Writing file:
FileOutputStream fos = new FileOutputStream("awesomefile.csv");
OutputStreamWriter osw = new OutputStreamWriter(fos, "UTF-8");
CSVWriter writer = new CSVWriter(osw);
...
String[] row = {
"123",
"John",
"Smith",
"39",
"I said \"Hey, I am 5'10\".\""
};
writer.writeNext(row);
...
writer.close();
osw.close();
os.close();
Reading file:
FileInputStream fis = new FileInputStream("awesomefile.csv");
InputStreamReader isr = new InputStreamReader(fis, "UTF-8");
CSVReader reader = new CSVReader(isr);
for (String[] row; (row = reader.readNext()) != null;) {
System.out.println(Arrays.toString(row));
}
reader.close();
isr.close();
fis.close();
* You can download it from here.

Excel has to be able to handle the exact same situation.
Put those things into Excel, save them as CSV, and examine the file with a text editor. Then you'll know the rules Excel is applying to these situations.
Make Java produce the same output.
The formats used by Excel are published, by the way...
****Edit 1:**** Here's what Excel does
****Edit 2:**** Note that php's fputcsv does the same exact thing as excel if you use " as the enclosure.
rdeslonde#mydomain.com
Richard
"This is what I think"
gets transformed into this:
Email,Fname,Quoted
rdeslonde#mydomain.com,Richard,"""This is what I think"""

Thanks to both Tony and Paul for the quick feedback, its very helpful. I actually figure out a solution through POJO. Here it is:
if (cell_value.indexOf("\"") != -1 || cell_value.indexOf(",") != -1) {
cell_value = cell_value.replaceAll("\"", "\"\"");
row.append("\"");
row.append(cell_value);
row.append("\"");
} else {
row.append(cell_value);
}
in short if there is special character like comma or double quote within the string in side the cell, then first escape the double quote("\"") by adding additional double quote (like "\"\""), then put the whole thing into a double quote (like "\""+theWholeThing+"\"" )

You could also look at how Python writes Excel-compatible csv files.
I believe the default for Excel is to double-up for literal quote characters - that is, literal quotes " are written as "".

If you're using CSVWriter. Check that you don't have the option
.withQuotechar(CSVWriter.NO_QUOTE_CHARACTER)
When I removed it the comma was showing as expected and not treating it as new column

"cell one","cell "" two","cell "" ,three"
Save this to csv file and see the results, so double quote is used to escape itself
Important Note
"cell one","cell "" two", "cell "" ,three"
will give you a different result because there is a space after the comma, and that will be treated as "

String stringWithQuates = "\""+ "your,comma,separated,string" + "\"";
this will retain the comma in CSV file

In openCSV, use below method to create csvWriter obj,
CSVWriter csvWriter = new CSVWriter(writer, CSVWriter.DEFAULT_SEPARATOR, CSVWriter.DEFAULT_ESCAPE_CHARACTER, CSVWriter.DEFAULT_LINE_END, CSVWriter.DEFAULT_QUOTE_CHARACTER);
In this, DEFAULT_QUOTE_CHARACTER is very important.
It will work perfectly, If you want to insert any ',' or '"' in csv file.

Java - Load file, replace string, save

I have a program that loads lines from a user file, then selects the last part of the String (which would be an int)
Here's the style it's saved in:
nameOfValue = 0
nameOfValue2 = 0
and so on. I have selected the value for sure - I debugged it by printing. I just can't seem to save it back in.
if(nameOfValue.equals(type)) {
System.out.println(nameOfValue+" equals "+type);
value.replace(value, Integer.toString(Integer.parseInt(value)+1));
}
How would I resave it? I've tried bufferedwriter but it just erases everything in the file.

My suggestion is, save all the contents of the original file (either in memory or in a temporary file; I'll do it in memory) and then write it again, including the modifications. I believe this would work:
public static void replaceSelected(File file, String type) throws IOException {
// we need to store all the lines
List<String> lines = new ArrayList<String>();
// first, read the file and store the changes
BufferedReader in = new BufferedReader(new FileReader(file));
String line = in.readLine();
while (line != null) {
if (line.startsWith(type)) {
String sValue = line.substring(line.indexOf('=')+1).trim();
int nValue = Integer.parseInt(sValue);
line = type + " = " + (nValue+1);
}
lines.add(line);
line = in.readLine();
}
in.close();
// now, write the file again with the changes
PrintWriter out = new PrintWriter(file);
for (String l : lines)
out.println(l);
out.close();
}
And you'd call the method like this, providing the File you want to modify and the name of the value you want to select:
replaceSelected(new File("test.txt"), "nameOfValue2");

I think most convenient way is:
Read text file line by line using BufferedReader
For each line find the int part using regular expression and replace
it with your new value.
Create a new file with the newly created text lines.
Delete source file and rename your new created file.
Please let me know if you need the Java program implemented above algorithm.

Hard to answer without the complete code...
Is value a string ? If so the replace will create a new string but you are not saving this string anywhere. Remember Strings in Java are immutable.
You say you use a BufferedWriter, did you flush and close it ? This is often a cause of values mysteriously disappearing when they should be there. This exactly why Java has a finally keyword.
Also difficult to answer without more details on your problem, what exactly are you trying to acheive ? There may be simpler ways to do this that are already there.