how to detect line breaks in java

Question

yes i have read a few of the other posts on line breaks but they are not helping me.

my Java program is supposed to read a .PHP file and split the source code into a line by line format. the problem is that i cant seem to really distinguish one line break from another.

i tried to use /n didnt work.... i tried to use /r/n didnt work.....

here is an example

step_B = step_A.replaceAll("\n", "XXX");

i tried to replace the line breaks with the word XXX but it didnt work.

here is a sample of the php i wanted to split, i managed to separate the lines using ; as delimiter but i got to refine it a bit more now.

$ALL_AUTH = mysql_fetch_row($author_lookup);
    //preparing to display the output in the table
    echo "<tr>";

i wanted it to output something like this

INFO:  $ALL_AUTH = mysql_fetch_row($author_lookup)

INFO:  //preparing to display the output in the table 

INFO:  echo "<tr>"

but instead i get this

INFO:  $ALL_AUTH = mysql_fetch_row($author_lookup)

INFO:  //preparing to display the output in the table  echo "<tr>"

the app cannot seem to detect that there is a newline after the comment ends at the word "table". is there a way to do this ? preferably without hardcoding the word table or anything like that.

Ohhhh i found the mistake, i used a transform via some regex on the block of code at an earlier stage and that messed up the newlines.... the code block became one massive line of text ! hence no line breaks thanks for your time guys !

Solution

If you have the data already in a String:

String[] lines = string.split("\r\n|\n|\r");
for (String line : lines) {
    System.out.println(line);
}

Or read the lines directly from a file:

BufferedReader br = new BufferedReader(new FileReader("myfilename"));
String line = null;
while ((line = br.readLine()) != null) {
    System.out.println(line);
}

Java 7+ has a convenience method to read lines directly from the filesystem:

Path path = FileSystems.getDefault().getPath("myfilename");
List<String> lines = Files.readAllLines(path, Charset.defaultCharset());
for (String line : lines) {
    System.out.println(line);
}

Java does not do automatic charset detection, so you are responsible for setting the charset correctly when reading a text file; otherwise characters may not be read correctly. Don't forget to be tidy: .close() your file handles.

Comments

[Neet]

This or directly use a BufferedReader to read the text file line by line.