Console object implements functionality for
* printing Scala values on the terminal. There are also functions
* for reading specific values. Console also defines
* constants for marking up text on ANSI terminals.
*
* @author Matthias Zenger
* @version 1.0, 03/09/2003
*/
object Console {
// ANSI colors foreground
final val BLACK = "\033[30m"
final val RED = "\033[31m"
final val GREEN = "\033[32m"
final val YELLOW = "\033[33m"
final val BLUE = "\033[34m"
final val MAGENTA = "\033[35m"
final val CYAN = "\033[36m"
final val WHITE = "\033[37m"
// ANSI colors background
final val BLACK_B = "\033[40m"
final val RED_B = "\033[41m"
final val GREEN_B = "\033[42m"
final val YELLOW_B = "\033[43m"
final val BLUE_B = "\033[44m"
final val MAGENTA_B = "\033[45m"
final val CYAN_B = "\033[46m"
final val WHITE_B = "\033[47m"
// ANSI styles
final val RESET = "\033[0m"
final val BOLD = "\033[1m"
final val UNDERLINED = "\033[4m"
final val BLINK = "\033[5m"
final val REVERSED = "\033[7m"
final val INVISIBLE = "\033[8m"
private val outVar = new DynamicVariable[PrintStream](java.lang.System.out)
private val errVar = new DynamicVariable[PrintStream](java.lang.System.err)
private val inVar = new DynamicVariable[BufferedReader](
new BufferedReader(new InputStreamReader(java.lang.System.in)))
def out = outVar.value
def err = errVar.value
def in = inVar.value
/** Set the default output stream.
*
* @param out the new output stream.
*/
def setOut(out: PrintStream) { outVar.value = out }
/** Set the default output stream for the duration
* of execution of one thunk.
*
* @param out the new output stream.
* @param thunk the code to execute with
* the new output stream active
* @return ...
*/
def withOut[T](out: PrintStream)(thunk: =>T): T =
outVar.withValue(out)(thunk)
/** Set the default output stream.
*
* @param out the new output stream.
*/
def setOut(out: OutputStream): Unit =
setOut(new PrintStream(out))
/** Set the default output stream for the duration
* of execution of one thunk.
*
* @param out the new output stream.
* @param thunk the code to execute with
* the new output stream active
* @return ...
*/
def withOut[T](out: OutputStream)(thunk: =>T): T =
withOut(new PrintStream(out))(thunk)
/** Set the default error stream.
*
* @param err the new error stream.
*/
def setErr(err: PrintStream) { errVar.value = err }
/** Set the default error stream for the duration
* of execution of one thunk.
*
* @param err the new error stream.
* @param thunk the code to execute with
* the new error stream active
* @return ...
*/
def withErr[T](err: PrintStream)(thunk: =>T): T =
errVar.withValue(err)(thunk)
/** Set the default error stream.
*
* @param err the new error stream.
*/
def setErr(err: OutputStream): Unit =
setErr(new PrintStream(err))
/** Set the default error stream for the duration
* of execution of one thunk.
*
* @param err the new error stream.
* @param thunk the code to execute with
* the new error stream active
* @return ...
*/
def withErr[T](err: OutputStream)(thunk: =>T): T =
withErr(new PrintStream(err))(thunk)
/** Set the default input stream.
*
* @param reader specifies the new input stream.
*/
def setIn(reader: Reader) {
inVar.value = new BufferedReader(reader)
}
/** Set the default input stream for the duration
* of execution of one thunk.
*
* @param in the new input stream.
* @param thunk the code to execute with
* the new input stream active
*/
def withIn[T](reader: Reader)(thunk: =>T): T =
inVar.withValue(new BufferedReader(reader))(thunk)
/** Set the default input stream.
*
* @param in the new input stream.
*/
def setIn(in: InputStream) {
setIn(new InputStreamReader(in))
}
/** Set the default input stream for the duration
* of execution of one thunk.
*
* @param in the new input stream.
* @param thunk the code to execute with
* the new input stream active
*/
def withIn[T](in: InputStream)(thunk: =>T): T =
withIn(new InputStreamReader(in))(thunk)
/** Print an object on the terminal.
*
* @param obj the object to print.
*/
def print(obj: Any) {
out.print(if (null == obj) "null" else obj.toString())
}
/** Flush the output stream. This function is required when partial
* output (i.e. output not terminated by a new line character) has
* to be made visible on the terminal.
*/
def flush() { out.flush() }
/** Print a new line character on the terminal.
*/
def println() { out.println() }
/** Print out an object followed by a new line character.
*
* @param x the object to print.
*/
def println(x: Any) { out.println(x) }
/** * Prints its arguments as a formatted string, based on a string * pattern (in a fashion similar to printf in C). *
*
* The interpretation of the formatting patterns is described in
*
* java.util.Formatter.
*
null if the end of the
* input stream has been reached.
*
* @return the string read from the terminal.
*/
def readLine(): String = in.readLine()
/** Print a formatted text and read a full line from the terminal.
* Returns null if the end of the input stream has been reached.
*
* @param text the format of the text to print out.
* @param args the parameters used to instantiate the format.
* @return the string read from the terminal.
*/
def readLine(text: String, args: Any*): String = {
printf(text, args: _*)
readLine()
}
/** Read a boolean value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @return the boolean value read from the terminal.
* @throws java.io.EOFException
*/
def readBoolean(): Boolean = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s.toLowerCase() match {
case "true" => true
case "t" => true
case "yes" => true
case "y" => true
case _ => false
}
}
/** Read a byte value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @throws java.io.EOFException
*/
def readByte(): Byte = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s.toByte
}
/** Read a short value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @throws java.io.EOFException
*/
def readShort(): Short = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s.toShort
}
/** Read a char value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @throws java.io.EOFException
*/
def readChar(): Char = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s charAt 0
}
/** Read an int value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @throws java.io.EOFException
*/
def readInt(): Int = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s.toInt
}
/** Read an int value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @throws java.io.EOFException
*/
def readLong(): Long = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s.toLong
}
/** Read a float value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @throws java.io.EOFException
*/
def readFloat(): Float = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s.toFloat
}
/** Read a double value from the terminal.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @throws java.io.EOFException
*/
def readDouble(): Double = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
s.toDouble
}
/** Read in some structured input, specified by a format specifier.
* See class java.text.MessageFormat for details of
* the format specification.
* Throws EOFException if the end of the
* input stream has been reached.
*
* @param format the format of the input.
* @return a list of all extracted values.
* @throws java.io.EOFException
*/
def readf(format: String): List[Any] = {
val s = readLine()
if (s == null)
throw new java.io.EOFException("Console has reached end of input")
else
textComponents(new MessageFormat(format).parse(s))
}
/** Read in some structured input, specified by a format specifier.
* Opposed to readf, this function only returns the
* first value extracted from the input according to the format
* specification.
*
* @param format ...
* @return ...
*/
def readf1(format: String): Any = readf(format).head
/** Read in some structured input, specified by a format specifier.
* Opposed to readf, this function only returns the
* first two values extracted from the input according to the format
* specification.
*
* @param format ...
* @return ...
*/
def readf2(format: String): (Any, Any) = {
val res = readf(format)
(res.head, res.tail.head)
}
/** Read in some structured input, specified by a format specifier.
* Opposed to readf, this function only returns the
* first three values extracted from the input according to the format
* specification.
*
* @param format ...
* @return ...
*/
def readf3(format: String): (Any, Any, Any) = {
val res = readf(format)
(res.head, res.tail.head, res.tail.tail.head)
}
private def textComponents(a: Array[AnyRef]): List[Any] = {
var i: Int = a.length - 1
var res: List[Any] = Nil
while (i >= 0) {
res = (a(i) match {
case x: java.lang.Boolean => x.booleanValue()
case x: java.lang.Byte => x.byteValue()
case x: java.lang.Short => x.shortValue()
case x: java.lang.Character => x.charValue()
case x: java.lang.Integer => x.intValue()
case x: java.lang.Long => x.longValue()
case x: java.lang.Float => x.floatValue()
case x: java.lang.Double => x.doubleValue()
case x => x
}) :: res;
i -= 1
}
res
}
}