streamreadline.java

UML设计测试工具

/*
 * USE - UML based specification environment
 * Copyright (C) 1999-2004 Mark Richters, University of Bremen
 *
 * This program 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 2 of the
 * License, or (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* $ProjectHeader: use 2-3-0-release.1 Mon, 12 Sep 2005 20:18:33 +0200 green $ */

package org.tzi.use.util.input;

import java.io.BufferedReader;
import java.io.IOException;

import org.tzi.use.util.USEWriter;


/**
 * A Readline implementation using a BufferedReader as source.
 * 
 * @version     $ProjectVersion: 2-3-0-release.1 $
 * @author      Mark Richters 
 */
public class StreamReadline implements Readline {
    private BufferedReader fBufferedReader;
    private String fStaticPrompt;
    private boolean fDoEcho;
    private boolean fDoProtocol;

    /**
     * Constructs a new StreamReadline. If echoInput is true, each
     * line read will be echoed to stdout. staticPrompt may be used to
     * overwrite the prompt passed to the readline method.
     */
     StreamReadline(BufferedReader reader,
                          boolean doEcho,
                          boolean doProtocol,
                          String staticPrompt) {
        fBufferedReader = reader;
        fStaticPrompt = staticPrompt;
        fDoEcho = doEcho;
        fDoProtocol = doProtocol;
        //OldUSEWriter.getInstance().setCmdReadPrompt( fStaticPrompt );
    }

    public StreamReadline(BufferedReader reader,
                          boolean doEcho,boolean doProtocol) {
        this(reader, doEcho, doProtocol, null);
    }

    public boolean doEcho() {
        return fDoEcho;
    }
    
    public boolean doProtocol() {
        return fDoProtocol;
    }
    
    /**
     * Reads a line of text from the underlying BufferedReader.
     *
     * @return     A String containing the contents of the line, not including
     *             any line-termination characters, or null if the end of the
     *             stream has been reached.
     *
     * @exception  IOException  If an I/O error occurs.
     */
    public String readline(String prompt) throws IOException {
        if (fStaticPrompt != null ) {
            USEWriter.getInstance().getNoProtocolOut().print(fStaticPrompt);
        } else
            USEWriter.getInstance().getNoProtocolOut().print(prompt);
        String line = fBufferedReader.readLine();
        if (fDoEcho )
            if (line != null ) {
                System.out.println(line);
            } else 
            System.out.println();
        return line;
    }   

    /**
     * Closes the Readline stream.
     */
    public void close() throws IOException {
        fBufferedReader.close();
    }

    // The following operations are just noops.

    public void usingHistory() {}

    public void readHistory(String filename) {}

    public void writeHistory(String filename) {}
}