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    import org.crsh.text.Chunk;
024    
025    import java.io.Closeable;
026    import java.io.IOException;
027    
028    public interface Term extends Closeable, ScreenContext<Chunk> {
029    
030      /**
031       * Retrieves the value of a property specified by this Term
032       *
033       * @param name name of the term property
034       * @return value of the term property
035       */
036      String getProperty(String name);
037    
038      /**
039       * Take control of the alternate buffer. When the alternate buffer is already used
040       * nothing happens. The buffer switch should occur when then {@link #flush()} method
041       * is invoked.
042       *
043       * @return true if the alternate buffer is shown
044       */
045      boolean takeAlternateBuffer() throws IOException;
046    
047      /**
048       * Release control of the alternate buffer. When the normal buffer is already used
049       * nothing happens. The buffer switch should occur when then {@link #flush()} method
050       * is invoked.
051       *
052       * @return true if the usual buffer is shown
053       */
054      boolean releaseAlternateBuffer() throws IOException;
055    
056      /**
057       * Set the echo mode on the term.
058       *
059       * @param echo the echo mode
060       */
061      void setEcho(boolean echo);
062    
063      /**
064       * Read the next term event. This operation is a blocking operation that blocks until data is available or until
065       * term is closed.
066       *
067       * @return the next term event
068       * @throws IOException any io exception
069       */
070      TermEvent read() throws IOException;
071    
072      /**
073       * Returns the direct buffer, any char appended in the returned appendable will translate into an
074       * insertion in the buffer.
075       *
076       * @return the insert buffer.
077       */
078      Appendable getDirectBuffer();
079    
080      /**
081       * Returns the current buffer content to the cursor;
082       *
083       * @return the buffer
084       */
085      CharSequence getBuffer();
086    
087      /**
088       * Append a line to the term history.
089       *
090       * @param line the history line to append
091       */
092      void addToHistory(CharSequence line);
093    
094    }