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Is there a way for Java Scanner to include '\n' when it is reading lines?

Is there any way for java.util.Scanner to include the newline escape character when reading from a file?
This is my code:
File myFile = new File("file.txt");
Scanner myReader = new Scanner(myFile);
String content = "";
while(myReader.hasNextLine()) {
content += myReader.nextLine();
}
System.out.println(content);
myReader.close();
When it reads from the file, it doesn't include '\n' or any new lines. Does anyone know how to do this?
Thanks

When it reads from the file, it doesn't include '\n' or any new lines.
Does anyone know how to do this?
You can add the new line explicitly as follows:
while(myReader.hasNextLine()) {
content += myReader.nextLine() + "\n";
}
I also recommend you use StringBuilder instead of String for appending in a loop.
StringBuilder content = new StringBuilder();
while (myReader.hasNextLine()) {
content.append(myReader.nextLine()).append(System.lineSeparator());
// or the following
// content.append(myReader.nextLine()).append('\n');
}
Check StringBuilder vs String concatenation in toString() in Java to learn more about it.

If you you just want to read in lines and the line terminator you can do it by changing the behavior of Scanner.next(). If you run the following it will take in the line and the new line terminator as one unit.
\\z is a regex directive that says to include the line terminator.
Scanner scan = new Scanner(System.in);
scan.useDelimiter("\\z");
for (int i = 0; i < 5; i++) {
String line = scan.next();
System.out.println(line + "on next line");
}
To read from a file, try this.
try {
Scanner scan = new Scanner(new File("f:/Datafile.txt"));
scan.useDelimiter("\\z");
while (scan.hasNextLine()) {
String line = scan.next();
System.out.print(line);
}
} catch (FileNotFoundException fe) {
fe.printStackTrace();
}

change specific text in text file with scanner class (java)

I write this code that can search for the some specific text (such as word) in the text file with scanner class, but i want also to replace (old text to the new text) in the same old text locuation.
i find in the internet that i must used replaceAll method like ( replaceAll(old, new); )
but it does't work with the scanner class.
This is my code, it just search (if it existed ) write new text in new line without change the old one.
Do i need to change the method (to get the data) form scanner to FileReader ??
File file = new File("C:\\Users....file.txt");
Scanner input = new Scanner(System.in);
System.out.println("Enter the content you want to change:");
String Uinput = input.nextLine();
System.out.println("You want to change it to:");
String Uinput2 = input.nextLine();
Scanner scanner = new Scanner(file).useDelimiter(",");
BufferedWriter writer = new BufferedWriter(new FileWriter(file, true));
while (scanner.hasNextLine()) {
String lineFromFile = scanner.next();
if (lineFromFile.contains(Uinput)) {
lineFromFile = Uinput2;
writer.write(lineFromFile);
writer.close();
System.out.println("changed " + Uinput + " tO " + Uinput2);
break;
}
else if (!lineFromFile.contains(Uinput)){
System.out.println("Don't found " + Uinput);
break;
}
}

You cannot read from a file, then write to that same file. You need 2 different files.
while (read line from input file) {
if (NOT matches your search pattern)
write line to output file.
else { // matches
write start of line to your search pattern.
write your replace string
write from end of search pattern to end of line.
}
}
Unless your replace string is the same size as your search string, yes, you'll have to use 2 files. Consider the file:
Blah
Blah
Blah
Now replace the letter 'a' with "The quick Brown Fox". If you replace the first line, you've overwritten the rest of the file. Now you can't read the 2nd line, so YES, you'll have to use 2 files.

Here's another answer based on #Sedrick comment and your code.
I'm adding it to your pseudo code.
File file = new File("C:\\Users....file.txt");
Scanner input = new Scanner(System.in);
System.out.println("Enter the content you want to change:");
String Uinput = input.nextLine();
System.out.println("You want to change it to:");
String Uinput2 = input.nextLine();
Scanner scanner = new Scanner(file).useDelimiter(",");
java.util.List<String> tempStorage = new ArrayList<>();
while (scanner.hasNextLine()) {
String lineFromFile = scanner.next();
tempStorage.add(lineFromFile);
}
// close input file here
// Open your write file here (same file = overwrite).
// now loop through temp storage searching for input string.
for (String currentLine : tempStorage ) {
if (!lcurrentLine.contains(Uinput)){
String temp = currentLine.replace(Uinput, Uinput2);
write a line using temp variable
} else { // not replaced
write a line using currentLine;
}
// close write file here
By the way, you'll have to encase the reads writes with try catch to trap for IOExceptions. That's how I knew it was pseudo code. There are plenty of examples for reading/writing a file on this web site. It's easy to search for.

Scanner only recognizes certain lines in a text file but not others

I have a txt file of names and genders that I imported for this java program. The scanners are supposed take a user input (name and gender) and compare it line by line to find it within the text file and then print the line at which the name was found. However, only some names work and not others. I think it may be because the program only reads every other line but im not sure if thats the problem, or how to fix it.
Link to the name file: http://courses.cs.washington.edu/courses/cse142/16au/homework/names.txt
public static void fileSearch() throws FileNotFoundException {
System.out.println("What name are you looking for?");
Scanner scan = new Scanner(System.in);
String name = scan.nextLine();
String gender = scan.nextLine();
File file = new File("names.txt");
Scanner fileScan = new Scanner(file);
while (fileScan.hasNextLine()) {
String line = fileScan.nextLine();
Scanner lineScan = new Scanner(line);
String nameText = lineScan.next();
String genderText = lineScan.next();
if (name.equalsIgnoreCase(nameText) && gender.equalsIgnoreCase(genderText)) {
System.out.println(line);
}
}
}
}

Trying to get Scanner to scan entire file

String userInput = stdin.nextLine();
file = new File(userInput);
Scanner fileScanner = new Scanner(file);
while(fileScanner.hasNext()) {
fileContents = fileScanner.nextLine();
}
So I'm trying to figure out how I can get my variable fileContents to hold all of the file from the scanner. with the current way I have it setup the variable fileContents is left with only the last line of the .txt file. for what I'm doing I need it to hold the entire text from the file. spaces, chars and all.
I'm sure there is a simple fix to this I'm just very new to java/coding.

You need to change
fileContents += fileScanner.nextLine();
or
fileContents =fileContents + fileScanner.nextLine();
With your approach you are reassigning the fileContents value instead you need to concat the next line.

String userInput = stdin.nextLine();
file = new File(userInput);
StringBuilder sb = new StringBuilder();
Scanner fileScanner = new Scanner(file);
while(fileScanner.hasNext()) {
sb.append(fileScanner.nextLine()+"\n");
}
System.out.println(sb.toString());
Or follow the #singhakash's answer, because his one is faster performance wise I presume. But I used a StringBuilder to give you an idea that you're 'appending' or in other words, just adding to the data that you wish to use. Where as with your way, you're going to be getting the last line of the text because it keeps overriding the previous data.

You can use below as well:
Scanner sc = new Scanner(new File("C:/abc.txt"));
String fileContents = sc.useDelimiter("\\A").next();
You don't have to use while loop in this case.

extract matched line from text file

a:b:c:d:e
bb:cc:dd:ee:ff
ccc:ddd:eee:fff:ggg
I have a textfile content above. I am trying to compare my user input with the text file. For example
cc:dd
When it is found, I need to retrieve the entire line. How can I retrieve the line which my user input? I have tried using while(scanner.hasNext()) but I could not get my desire outcome.

With standard Java libraries:
File file = new File("file.txt");
String word = "abc";
Scanner scanner = null;
try {
scanner = new Scanner(file);
} catch(FileNotFoundException e) {
//handle this
}
//now read the file line by line
while (scanner.hasNextLine()) {
String line = scanner.nextLine();
if(line.contains(word)) {
System.out.println(line);
}
}
scanner.close();