Can I peek on a BufferedReader?

Question

Is there a way to check if in BufferedReader object is something to read? Something like C++ cin.peek(). Thanks.

Answer 1

The normal idiom is to check in a loop if BufferedReader#readLine() doesn't return null. If end of stream is reached (e.g. end of file, socket closed, etc), then it returns null.

E.g.

BufferedReader reader = new BufferedReader(someReaderSource);
String line = null;
while ((line = reader.readLine()) != null) {
    // ...
}

If you don't want to read in lines (which is by the way the major reason a BufferedReader is been chosen), then use BufferedReader#ready() instead:

BufferedReader reader = new BufferedReader(someReaderSource);
while (reader.ready()) {
    int data = reader.read();
    // ...
}