Reading an InputStream coverting it into a String in Java

Question

Suppose I have a java.io.InputStream object, how can I process it to produce a String?
Let's sat my InputStream has text data, which I need to convert into a String so that I can write it to a log file.
Can someone tell me an easy way to either read the InputStream as a String or convert it into one?

public String convertStreamToString(InputStream is) { ...... }

Answer 1

Use Apache commons IOUtils and copy the InputStream into a StringWriter like this:

StringWriter writer = new StringWriter();
IOUtils.copy(inputStream, writer, encoding);
String theString = writer.toString();

or else

// NB: does not close inputStream, you'll have to use try-with-resources for that
String theString = IOUtils.toString(inputStream, encoding); 

Also, you could use ByteArrayOutputStream if you don't want to mix your Streams and Writers

Answer 2

Apache Commons allows:

String myString = IOUtils.toString(myInputStream, "UTF-8");

And you could of course choose other character encodings besides UTF-8