001    /*
002     * Copyright (C) 2012 eXo Platform SAS.
003     *
004     * This is free software; you can redistribute it and/or modify it
005     * under the terms of the GNU Lesser General Public License as
006     * published by the Free Software Foundation; either version 2.1 of
007     * the License, or (at your option) any later version.
008     *
009     * This software is distributed in the hope that it will be useful,
010     * but WITHOUT ANY WARRANTY; without even the implied warranty of
011     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012     * Lesser General Public License for more details.
013     *
014     * You should have received a copy of the GNU Lesser General Public
015     * License along with this software; if not, write to the Free
016     * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017     * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018     */
019    
020    package org.crsh.term;
021    
022    import org.crsh.shell.ScreenContext;
023    
024    import java.io.Closeable;
025    import java.io.IOException;
026    
027    public interface Term extends Closeable, ScreenContext {
028    
029      /**
030       * Retrieves the value of a property specified by this Term
031       *
032       * @param name name of the term property
033       * @return value of the term property
034       */
035      String getProperty(String name);
036    
037      /**
038       * Take control of the alternate buffer. When the alternate buffer is already used
039       * nothing happens. The buffer switch should occur when then {@link #flush()} method
040       * is invoked.
041       *
042       * @return true if the alternate buffer is shown
043       */
044      boolean takeAlternateBuffer() throws IOException;
045    
046      /**
047       * Release control of the alternate buffer. When the normal buffer is already used
048       * nothing happens. The buffer switch should occur when then {@link #flush()} method
049       * is invoked.
050       *
051       * @return true if the usual buffer is shown
052       */
053      boolean releaseAlternateBuffer() throws IOException;
054    
055      /**
056       * Set the echo mode on the term.
057       *
058       * @param echo the echo mode
059       */
060      void setEcho(boolean echo);
061    
062      /**
063       * Read the next term event. This operation is a blocking operation that blocks until data is available or until
064       * term is closed.
065       *
066       * @return the next term event
067       * @throws IOException any io exception
068       */
069      TermEvent read() throws IOException;
070    
071      /**
072       * Returns the direct buffer, any char appended in the returned appendable will translate into an
073       * insertion in the buffer.
074       *
075       * @return the insert buffer.
076       */
077      Appendable getDirectBuffer();
078    
079      /**
080       * Returns the current buffer content to the cursor;
081       *
082       * @return the buffer
083       */
084      CharSequence getBuffer();
085    
086      /**
087       * Append a line to the term history.
088       *
089       * @param line the history line to append
090       */
091      void addToHistory(CharSequence line);
092    
093    }