OutputStream.java

/*
 * $Id: OutputStream.java 536 2008-02-19 06:03:27Z weiju $
 * 
 * Created on 10/05/2005
 * Copyright 2005-2008 by Wei-ju Wu
 * This file is part of The Z-machine Preservation Project (ZMPP).
 *
 * ZMPP is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * ZMPP is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ZMPP.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.zmpp.io;

/**
 * This interface defines an output stream in the Z-machine.
 *
 * @author Wei-ju Wu
 * @version 1.0
 */
public interface OutputStream {

    /**
     * Prints a ZSCII character to the stream. The isInput parameter is needed
     * to implement edit buffers.
     *
     * @param zchar the ZSCII character to print
     * @param isInput is true if the character is an echo to the input
     */
    void print(char zchar, boolean isInput);

    /**
     * This function is only used by the input function in order to echo a
     * delete into the output. Output streams do not need to remember their
     * previous output, but the virtual machine will, and provides that
     * character as the argument.
     *
     * @param zchar the character to delete
     */
    void deletePrevious(char zchar);

    /**
     * Close underlying resources.
     */
    void close();

    /**
     * Flushes the output.
     */
    void flush();

    /**
     * Enables/disables this output stream.
     *
     * @param flag true to enable, false to disable
     */
    void select(boolean flag);

    /**
     * Determine, if this stream is selected.
     *
     * @return true if selected, false if deselected
     */
    boolean isSelected();
}