/** Clear the screen by issuing the ANSI "clear screen" code. */
public boolean clearScreen() throws IOException {
if (!terminal.isANSISupported()) {
return false;
}
// send the ANSI code to clear the screen
printString(((char) 27) + "[2J");
flushConsole();
// then send the ANSI code to go to position 1,1
printString(((char) 27) + "[1;1H");
flushConsole();
redrawLine();
return true;
}
/** Issue an audible keyboard bell, if {@link #getBellEnabled} return true. */
public final void beep() throws IOException {
if (!(getBellEnabled())) {
return;
}
printCharacter(KEYBOARD_BELL);
// need to flush so the console actually beeps
flushConsole();
}
/** Clear ahead the specified number of characters without moving the cursor. */
private final void clearAhead(final int num) throws IOException {
if (num == 0) {
return;
}
// debug ("clearAhead: " + num);
// print blank extra characters
printCharacters(' ', num);
// we need to flush here so a "clever" console
// doesn't just ignore the redundancy of a space followed by
// a backspace.
flushConsole();
// reset the visual cursor
back(num);
flushConsole();
}
/**
* Redraw the rest of the buffer from the cursor onwards. This is necessary for inserting text
* into the buffer.
*
* @param clear the number of characters to clear after the end of the buffer
*/
private final void drawBuffer(final int clear) throws IOException {
// debug ("drawBuffer: " + clear);
char[] chars = buf.buffer.substring(buf.cursor).toCharArray();
if (mask != null) Arrays.fill(chars, mask.charValue());
printCharacters(chars);
clearAhead(clear);
back(chars.length);
flushConsole();
}
/**
* Output the specified {@link Collection} in proper columns.
*
* @param stuff the stuff to print
*/
public void printColumns(final Collection stuff) throws IOException {
if ((stuff == null) || (stuff.size() == 0)) {
return;
}
int width = getTermwidth();
int maxwidth = 0;
for (Iterator i = stuff.iterator();
i.hasNext();
maxwidth = Math.max(maxwidth, i.next().toString().length())) {;
}
StringBuffer line = new StringBuffer();
int showLines;
if (usePagination) showLines = getTermheight() - 1; // page limit
else showLines = Integer.MAX_VALUE;
for (Iterator i = stuff.iterator(); i.hasNext(); ) {
String cur = (String) i.next();
if ((line.length() + maxwidth) > width) {
printString(line.toString().trim());
printNewline();
line.setLength(0);
if (--showLines == 0) { // Overflow
printString(loc.getString("display-more"));
flushConsole();
int c = readVirtualKey();
if (c == '\r' || c == '\n') showLines = 1; // one step forward
else if (c != 'q') showLines = getTermheight() - 1; // page forward
back(loc.getString("display-more").length());
if (c == 'q') break; // cancel
}
}
pad(cur, maxwidth + 3, line);
}
if (line.length() > 0) {
printString(line.toString().trim());
printNewline();
line.setLength(0);
}
}
/** Output a platform-dependant newline. */
public final void printNewline() throws IOException {
printString(CR);
flushConsole();
}
/** Clear the line and redraw it. */
public final void redrawLine() throws IOException {
printCharacter(RESET_LINE);
flushConsole();
drawLine();
}
/**
* Read a line from the <i>in</i> {@link InputStream}, and return the line (without any trailing
* newlines).
*
* @param prompt the prompt to issue to the console, may be null.
* @return a line that is read from the terminal, or null if there was null input (e.g.,
* <i>CTRL-D</i> was pressed).
*/
public String readLine(final String prompt, final Character mask) throws IOException {
this.mask = mask;
if (prompt != null) this.prompt = prompt;
try {
terminal.beforeReadLine(this, this.prompt, mask);
if ((this.prompt != null) && (this.prompt.length() > 0)) {
out.write(this.prompt);
out.flush();
}
// if the terminal is unsupported, just use plain-java reading
if (!terminal.isSupported()) {
return readLine(in);
}
while (true) {
int[] next = readBinding();
if (next == null) {
return null;
}
int c = next[0];
int code = next[1];
if (c == -1) {
return null;
}
boolean success = true;
switch (code) {
case EXIT: // ctrl-d
if (buf.buffer.length() == 0) {
return null;
}
case COMPLETE: // tab
success = complete();
break;
case MOVE_TO_BEG:
success = setCursorPosition(0);
break;
case KILL_LINE: // CTRL-K
success = killLine();
break;
case CLEAR_SCREEN: // CTRL-L
success = clearScreen();
break;
case KILL_LINE_PREV: // CTRL-U
success = resetLine();
break;
case NEWLINE: // enter
moveToEnd();
printNewline(); // output newline
return finishBuffer();
case DELETE_PREV_CHAR: // backspace
success = backspace();
break;
case DELETE_NEXT_CHAR: // delete
success = deleteCurrentCharacter();
break;
case MOVE_TO_END:
success = moveToEnd();
break;
case PREV_CHAR:
success = moveCursor(-1) != 0;
break;
case NEXT_CHAR:
success = moveCursor(1) != 0;
break;
case NEXT_HISTORY:
success = moveHistory(true);
break;
case PREV_HISTORY:
success = moveHistory(false);
break;
case REDISPLAY:
break;
case PASTE:
success = paste();
break;
case DELETE_PREV_WORD:
success = deletePreviousWord();
break;
case PREV_WORD:
success = previousWord();
break;
case NEXT_WORD:
success = nextWord();
break;
case START_OF_HISTORY:
success = history.moveToFirstEntry();
if (success) setBuffer(history.current());
break;
case END_OF_HISTORY:
success = history.moveToLastEntry();
if (success) setBuffer(history.current());
break;
case CLEAR_LINE:
moveInternal(-(buf.buffer.length()));
killLine();
break;
case INSERT:
buf.setOvertyping(!buf.isOvertyping());
break;
case UNKNOWN:
default:
if (c != 0) { // ignore null chars
ActionListener action =
(ActionListener) triggeredActions.get(new Character((char) c));
if (action != null) action.actionPerformed(null);
else putChar(c, true);
} else success = false;
}
if (!(success)) {
beep();
}
flushConsole();
}
} finally {
terminal.afterReadLine(this, this.prompt, mask);
}
}
/** Move the visual cursor backwards without modifying the buffer cursor. */
private final void back(final int num) throws IOException {
printCharacters(BACKSPACE, num);
flushConsole();
}