Standard Input/Output
The System class in java.lang provides the "standard" IO streams System.in, System.out, and System.err.
System.in is an instance of InputStream.
System.out and System.err are instances of PrintStream.
PrintStream is a subclass of FilterOutputStream, which itself is a subclass of OutputStream.
PrintStream objects should not be instantiated; use other subclasses of FilterOutputStream for byte streams or PrintWriter objects for character streams.
PrintStream and PrintWriter define methods print(...) and println(...), which output any primitive type:
- System.out.println( "Enter character: " );
- int ch = System.in.read();
- System.out.println( (char) ch );