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.text.renderers;
021    
022    import org.crsh.text.Color;
023    import org.crsh.text.LineReader;
024    import org.crsh.text.LineRenderer;
025    import org.crsh.text.RenderAppendable;
026    
027    import java.lang.management.MemoryUsage;
028    
029    class MemoryUsageLineRenderer extends LineRenderer {
030    
031      /** . */
032      private final MemoryUsage usage;
033    
034      MemoryUsageLineRenderer(MemoryUsage usage) {
035        this.usage = usage;
036      }
037    
038      @Override
039      public int getActualWidth() {
040        return 32;
041      }
042    
043      @Override
044      public int getMinWidth() {
045        return 4;
046      }
047    
048      @Override
049      public int getMinHeight(int width) {
050        return 1;
051      }
052    
053      @Override
054      public int getActualHeight(int width) {
055        return 2;
056      }
057    
058      @Override
059      public LineReader reader(int width) {
060        return reader(width, 2);
061      }
062    
063      @Override
064      public LineReader reader(final int width, final int height) {
065        return new LineReader() {
066    
067          /** . */
068          private int index = 0;
069    
070          public boolean hasLine() {
071            return index < height;
072          }
073          public void renderLine(RenderAppendable to) throws IllegalStateException {
074            if (!hasLine()) {
075              throw new IllegalStateException();
076            }
077            long range = usage.getMax() - usage.getInit();
078            Color previous = null;
079    
080            if (usage.getMax() > 0) {
081              long a = (width * usage.getUsed()) / (usage.getMax());
082              long b = (width * usage.getCommitted()) / (usage.getMax());
083              for (int i = 0;i < width;i++) {
084                Color current;
085                if (i >= b) {
086                  // MAX
087                  current = Color.green;
088                } else if (i >= a) {
089                  // COMMITED
090                  current = Color.blue;
091                } else {
092                  // USED
093                  current = Color.cyan;
094                }
095                if (previous != current) {
096                  if (previous != null) {
097                    to.leaveStyle();
098                  }
099                  to.enterStyle(current.bg());
100                  previous = current;
101                }
102                to.append(' ');
103              }
104              if (previous != null) {
105                to.leaveStyle();
106              }
107            } else {
108              for (int i = 0;i < width;i++) {
109                to.append(' ');
110              }
111            }
112            index++;
113          }
114        };
115      }
116    }