Java The Complete Reference, Seventh Edition

588 Part II: The Java Library

Here is an example that demonstrates theConsoleclass:

// Demonstrate Console.

import java.io.*;

class ConsoleDemo {

public static void main(String args[]) {

String str;

Console con;

// Obtain a reference to the console.

con = System.console();

Method Description

void flush( ) Causes buffered output to be written physically to the

console.

Console format(StringfmtString,

Object...args)

Writesargsto the console using the format specified

byfmtString.

Console printf(StringfmtString,

Object...args)

Writesargsto the console using the format specified

byfmtString.

Reader reader( ) Returns a reference to aReaderconnected to the

console.

String readLine( ) Reads and returns a string entered at the keyboard.

Input stops when the user pressesENTER. If the end

of the console input stream has been reached,null

is returned. AnIOErroris thrown on failure.

String readLine(StringfmtString,

Object...args)

Displays a prompting string formatted as specified by

fmtStringandargs,and then reads and returns a string

entered at the keyboard. Input stops when the user

pressesENTER. If the end of the console input stream

has been reached,nullis returned. AnIOErroris

thrown on failure.

char[ ] readPassword( ) Reads a string entered at the keyboard. Input stops when

the user pressesENTER. The string is not displayed. If the

end of the console input stream has been reached,nullis

returned. AnIOErroris thrown on failure.

char[ ] readPassword(StringfmtString,

Object...args)

Displays a prompting string formatted as specified

byfmtStringandargs,and then reads a string entered

at the keyboard. Input stops when the user presses

ENTER. The string is not displayed. If the end of the

console input stream has been reached,nullis

returned. AnIOErroris thrown on failure.

PrintWriter writer( ) Returns a reference to aWriterconnected to the console.

TABLE 19-5 The Methods Defined byConsole