Read file from InputStream in different ways in SAP PI using Java Mapping. Snippets of code(s)

ReadFileFromInputStream.java

/*
* DIFFERENT WAYS TO READ & WRITE FILE USING JAVA MAPPING (PI)
* CODE SNIPPETS - CHOOSE ANY ONE WAY TO READ FILE
*/

public void transform(TransformationInput arg0, TransformationOutput arg1) throws StreamTransformationException 
{
  try{
      	InputStream in = (InputStream) arg0.getInputPayload().getInputStream();
	OutputStream out = (OutputStream) arg1.getOutputPayload().getOutputStream();
      
	//CODE SNIPPET 1
	int buffer;
	while ((buffer = in.read()) != -1)
	{
		out.write(buffer);
	}
	out.flush();
		  
	//CODE SNIPPET 2
	BufferedReader docInput = new BufferedReader(new InputStreamReader(in));
	String inputLine = "";
      	while ((inputLine = docInput.readLine()) != null) {
		sourcePayload.append(inputLine);
	}
	out.write(new String(sourcePayload).getBytes("UTF-8"));
		  
	//CODE SNIPPET 3
      	byte[] bytes = new byte[in.available()];  
      	in.read(bytes);  
      	out.write(bytes);
      	
  }catch (Exception ee){
      throw new StreamTransformationException("Issue in message parsing".concat(e.getMessage()));
  }
}