How do I save a String to a text file using Java?

Question

In Java, I have text from a text field in a String variable called "text".

How can I save the contents of the "text" variable to a file?

Answer 1

If you're simply outputting text, rather than any binary data, the following will work:

PrintWriter out = new PrintWriter("filename.txt"); 

Then, write your String to it, just like you would to any output stream:

out.println(text); 

You'll need exception handling, as ever. Be sure to call out.close() when you've finished writing.

If you are using Java 7 or later, you can use the "try-with-resources statement" which will automatically close your PrintStream when you are done with it (ie exit the block) like so:

try (PrintWriter out = new PrintWriter("filename.txt")) {     out.println(text); } 

You will still need to explicitly throw the java.io.FileNotFoundException as before.

Answer 2

Apache Commons IO contains some great methods for doing this, in particular FileUtils contains the following method:

static void writeStringToFile(File file, String data)  

which allows you to write text to a file in one method call:

FileUtils.writeStringToFile(new File("test.txt"), "Hello File"); 

You might also want to consider specifying the encoding for the file as well.