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BufferedReader multiple lines as one String

I am trying to read multiple lines from a file into an ArrayList as a String.
What I aim to do is to make it so the program reads from a file line by line until the reader sees a specific symbol (- in this case) and saves those rows as one single String. the code below makes every row a new string that it later adds to the list instead.
BufferedReader br = null;
br = new BufferedReader(new FileReader(file));
String read;
while ((read = br.readLine()) != null) {
String[] splited = read.split("-");
carList.add(Arrays.toString(splited));
}
for (String carList2 : carList) {
System.out.println(carList2);
System.out.println("x");
}

First, you need to check if the read line contains "-".
If it doesn't, concatenate the line with the previous ones.
If it does, concatenate only the first part of the line with the previous line.
This is a quick implementation:
BufferedReader br = null;
br = new BufferedReader(new FileReader(file));
String read;
String concatenatedLine = "";
while ((read = br.readLine()) != null) {
String[] splited = read.split("-");
// if line doesn't contains "-", splited[0] and read are equals
concatenatedLine += splited[0];
if (splited.length > 1) {
// if read line contains "-", there will be more than 1 element
carList.add(Arrays.toString(splited)); // add to the list
// store the second part of the line, in order to add it to the next ones
concatenatedLine = splited[1];
}
}
Note the output could not be what is expected if a line contains more than one -.
Also, concatenating String using + is not the best way to do it, but I let you find out more about that.

It's not very clear for me what is the output you desire.
If you would like to have each customer on one string without "-"
then you could try the following code:
while ((read = br.readLine()) != null) {
String splited = read.replace("-", " ");
carList.add(splited);
}

How to Check for empty line while parsing csv file?

From third party daily reports i will be getting a similar kind of csv file as shown below
07-Jan-2016
It is better to lead from behind and to put others in front, especially when you celebrate victory when nice things occur. You take the front line when there is danger. Then people will appreciate your leadership.
The main thing that you have to remember on this journey is, just be nice to everyone and always smile.
My requirement is that i need to put each paragraph (A line after space) each quote for above reference in a separate StringBuffer
My question how can i check for empty line ??
I tried with
if(line.contains(" "))
{
System.out.println("hjjjjjjjjjjjjjjjjk");
}
But the above is causing issue where ever there is a space
I am reading the csv file as shown below
String csvFile = "ip/ASRER070116.csv";
BufferedReader br = null;
String line = "";
try {
br = new BufferedReader(new FileReader(csvFile));
while ((line = br.readLine()) != null) {
if (line.startsWith(",")) {
line = line.replaceFirst(",", "");
}
System.out.println(line);
}
}
Could you please tell me how to resolve this ??

if (line != null && (line.trim().equals("") || line.trim().equals("\n"))){
System.out.println("this is empty line");
}

I would suggest you use trim() on the read line and then check if line.length == 0

You can use StringUtils.isBlank method from Apache Commons Lang
public static boolean isBlank(CharSequence cs)
Checks if a CharSequence is whitespace, empty ("") or null.
StringUtils.isBlank(null) = true
StringUtils.isBlank("") = true
StringUtils.isBlank(" ") = true
StringUtils.isBlank("bob") = false
StringUtils.isBlank(" bob ") = false

Read all lines with BufferedReader

I want to type a multiple line text into the console using a BufferedReader and when I hit "Enter" to find the sum of the length of the whole text. The problem is that it seems I'm getting into an infinite loop and when I press "Enter" the program does not come to an end. My code is below:
InputStreamReader instream = new InputStreamReader(System.in);
BufferedReader buffer = new BufferedReader(instream);
line= buffer.readLine();
while (line!=null){
length = length + line.length();
line= buffer.readLine();
}
Could you please tell me what I'm doing wrong?

One line of code using Java 8:
line = buffer.lines().collect(Collectors.joining());

The idiomatic way to read all of the lines is while ((line = buffer.readLine()) != null). Also, I would suggest a try-with-resources statement. Something like
try (InputStreamReader instream = new InputStreamReader(System.in);
BufferedReader buffer = new BufferedReader(instream)) {
long length = 0;
String line;
while ((line = buffer.readLine()) != null) {
length += line.length();
}
System.out.println("Read length: " + length);
} catch (Exception e) {
e.printStackTrace();
}
If you want to end the loop when you receive an empty line, add a test for that in the while loop
while ((line = buffer.readLine()) != null) {
if (line.isEmpty()) {
break;
}
length += line.length();
}
JLS-14.15. The break Statement says
A break statement transfers control out of an enclosing statement.

line will not be null when you press enter; it will be an empty string.
Take note of what the BufferedReader JavaDoc says about readLine():
Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed.
And readLine() returns:
A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached
So when you press [Enter], you are giving the BufferedReader a new line containing only \n, \r, or \r\n. This means that readLine() will return an empty string.
So try something like this instead:
InputStreamReader instream = new InputStreamReader(System.in);
BufferedReader buffer = new BufferedReader(instream);
line = buffer.readLine();
while( (line != null) && (!line.isEmpty()) ){
length = length + line.length();
line = buffer.readLine();
}

When you only press Enter the return from buffer.readLine(); isn't null it is an empty String.
Therefore you should change line != null to !line.equals("") (You could also change it to line.length() > 0)
Now your code will look something like this:
InputStreamReader instream = new InputStreamReader(System.in);
BufferedReader buffer = new BufferedReader(instream);
line = buffer.readLine();
while (!line.equals("")){
length = length + line.length();
line = buffer.readLine();
}
This should solve your problem. Hope this helped! :)

Since Java 8 you can use BufferedReader#lines method directly on buffered reader.
try (InputStreamReader in = new InputStreamReader(System.in);
BufferedReader buffer = new BufferedReader(in)) {
final int length = buffer.lines().mapToInt(String::length).sum();
System.out.println("Read length: " + length);
} catch (Exception e) {
e.printStackTrace();
}

Snarky answer: what you're doing wrong is only creating 2 objects in Java to do something... if you search, you can probably find a few more classes that extend BufferedReader or ExtendedBufferReader etc., and then it can be real Enterprise Java.
Now that i've gotten that out of my system: more useful answer. System.in is closed when you input EOF, which is Control-D under Linux and I think MacOS, and I think Control-Z plus enter under Windows. If you want to check for enter (or more specifically, two enters... one to finish the last line and one to indicate that you're done, which is essentially how http handles determining when the http headers are finished and it's time for the http body, then #dbank 's solution should be a viable option with a minor fix I'm going to try to make to move the ! inside the while predicate instead of !while.
(Edit #2: realized readLine strips the newline, so an empty line would "" instead of the newline, so now my code devolves to another answer with the EOF bit as an answer instead of comment)
Edit... that's weird, #dbank had answered while I was typing my answer, and I would have stopped had I not though mentioning the EOF alternative. To repeat his code from memory with the edit I was going to make:
InputStreamReader instream = new InputStreamReader(System.in);
BufferedReader buffer = new BufferedReader(instream);
line= buffer.readLine();
while (line != null && !line.equals("")){
length = length + line.length();
line= buffer.readLine();
}

Put every lines into String[] array. and second method get the number of lines contains in text file. I hope this might be useful to anyone..
public static void main(String... args) throws IOException {
String[] data = getLines();
for(String v : data) {
out.println(v);
}
}
public static String[] getLines() throws IOException {
BufferedReader bufferReader = new BufferedReader(new FileReader("C:\\testing.txt"));
String line = bufferReader.readLine();
String[] data = new String[getLinesLength()];
int i = 0;
while(line != null) {
data[i] = line;
line = bufferReader.readLine();
i++;
}
bufferReader.close();
return data;
}
public static int getLinesLength() throws IOException {
BufferedReader bufferReader = new BufferedReader(new FileReader("C:\\testing.txt"));
String line = bufferReader.readLine();
int size = 0;
while(line != null) {
size += 1;
line = bufferReader.readLine();
}
bufferReader.close();
return size;
}

Good example from #Russel Yang (https://stackoverflow.com/a/40412945/11079418).
Use this code, to add also a new line character after each line.
String lines = bufferedReader.lines().map(line -> line + "\n").collect(Collectors.joining());

Buffered Reader find specific line separator char then read that line

My program needs to read from a multi-lined .ini file, I've got it to the point it reads every line that start with a # and prints it. But i only want to to record the value after the = sign. here's what the file should look like:
#music=true
#Volume=100
#Full-Screen=false
#Update=true
this is what i want it to print:
true
100
false
true
this is my code i'm currently using:
#SuppressWarnings("resource")
public void getSettings() {
try {
BufferedReader br = new BufferedReader(new FileReader(new File("FileIO Plug-Ins/Game/game.ini")));
String input = "";
String output = "";
while ((input = br.readLine()) != null) {
String temp = input.trim();
temp = temp.replaceAll("#", "");
temp = temp.replaceAll("[*=]", "");
output += temp + "\n";
}
System.out.println(output);
}catch (IOException ex) {}
}
I'm not sure if replaceAll("[*=]", ""); truly means anything at all or if it's just searching for all for of those chars. Any help is appreciated!

Try following:
if (temp.startsWith("#")){
String[] splitted = temp.split("=");
output += splitted[1] + "\n";
}
Explanation:
To process lines only starting with desired character use String#startsWith method. When you have string to extract values from, String#split will split given text with character you give as method argument. So in your case, text before = character will be in array at position 0, text you want to print will be at position 1.
Also note, that if your file contains many lines starting with #, it should be wise not to concatenate strings together, but use StringBuilder / StringBuffer to add strings together.
Hope it helps.

Better use a StringBuffer instead of using += with a String as shown below. Also, avoid declaring variables inside loop. Please see how I've done it outside the loop. It's the best practice as far as I know.
StringBuffer outputBuffer = new StringBuffer();
String[] fields;
String temp;
while((input = br.readLine()) != null)
{
temp = input.trim();
if(temp.startsWith("#"))
{
fields = temp.split("=");
outputBuffer.append(fields[1] + "\n");
}
}

Using readline() and split()

The code below is mostly self explanatory. However, I am having trouble in two cases:
The while loop does not exit even with the command line is left blank.
If the input is test t1 the key variable is supposed to be "test" (using System.out.println(key)) does that, but, it still doesn't enter the if condition for some reason.
String[] broken_text = null; String text = "";
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
while((text = reader.readLine()) != null) {
broken_text = text.split(" ");
String first_key = broken_text[0];
if (first_key == "test") {
//some statements
}
}
I am not sure why this is happening, any help regarding the same will be much appreciated.

use equals() to check string equality.
if (first_key == "test") {
//some statements
}
should be
if (first_key.equals("test")) {
//some statements
}
your text will never be null because you declared it as
String text = "";
thus your while loop would be an infinite loop
change
String text = "";
to
String text = null;
or if you wanna leave your text="" string as empty string.
use
while(!(text = reader.readLine()).isEmpty())

The loop does not end because a blank line causes readLine() to return an empty string, not null.
The comparison fails because Strings must be compared with equals() not ==

The String text will never be null in this case. You can use:
while (!(text = reader.readLine()).isEmpty()) {

this should be your edited code:
String[] broken_text = null;
String text = "";
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
while((text = reader.readLine()) != null && !text.isEmpty()) {
broken_text = text.split(" ");
String first_key = broken_text[0];
if ( "test".equals(first_key)) {
//some statements
}
}
The reason changed (text = reader.readLine()) != null to (text = reader.readLine()) != null && !text.isEmpty() is because readLine() returns null when it encounters end-of-file as the first character, and it returns "" (empty string) when the first character is encounters is \r (carriage return), \n(line feed) , or \r\n(carriage return followed by line feed). And you must always check for null before checking for isEmpty().
On unix / Linux console end-of-file is [ctrl][d] and on DOS it is [ctrl][z]
Note: In case you want to read input from a file (where you are more likely to get an end-of-file) instead of console, then your reader will be initialised like this:
BufferedReader reader = new BufferedReader(new FileReader("d:\\a1.txt"));
(assuming your input data is in file: "d:\a1.txt".)