/*
    * Copyright (C) 2005-2015 Schlichtherle IT Services.
    * All rights reserved. Use is subject to license terms.
    */
   package net.java.truevfs.comp.jmx;
   
   import java.util.Date;
   import java.util.Objects;
   import javax.annotation.concurrent.ThreadSafe;
  import javax.management.MBeanAttributeInfo;
  import javax.management.MBeanInfo;
  import javax.management.StandardMBean;
  import static net.java.truecommons.cio.Entry.Access.*;
  import static net.java.truecommons.cio.Entry.Size.DATA;
  import static net.java.truecommons.cio.Entry.Size.STORAGE;
  import static net.java.truecommons.cio.Entry.UNKNOWN;
  import net.java.truecommons.cio.IoBuffer;
  
  /**
   * A view for an {@linkplain IoBuffer I/O buffer}.
   *
   * @param  <B> the type of the I/O buffer.
   * @author Christian Schlichtherle
   */
  @ThreadSafe
  public class JmxBufferView<B extends IoBuffer>
  extends StandardMBean implements JmxBufferMXBean {
  
      protected final B buffer;
  
      public JmxBufferView(B buffer) { this(JmxBufferMXBean.class, buffer); }
  
      protected JmxBufferView(
              final Class<? extends JmxBufferMXBean> type,
              final B buffer) {
          super(type, true);
          this.buffer = Objects.requireNonNull(buffer);
      }
  
      @Override
      protected String getDescription(MBeanInfo info) {
          return "An I/O buffer.";
      }
  
      @Override
      protected String getDescription(final MBeanAttributeInfo info) {
          switch (info.getName()) {
          case "Name":
              return "The name of this buffer.";
          case "SizeOfData":
              return "The data size of this buffer.";
          case "SizeOfStorage":
              return "The storage size of this buffer.";
          case "TimeCreatedDate":
              return "The time this buffer has been created.";
          case "TimeCreatedMillis":
              return "The time this buffer has been created in milliseconds.";
          case "TimeReadDate":
              return "The last time this buffer has been read or accessed.";
          case "TimeReadMillis":
              return "The last time this buffer has been read or accessed in milliseconds.";
          case "TimeWrittenDate":
              return "The last time this buffer has been written.";
          case "TimeWrittenMillis":
              return "The last time this buffer has been written in milliseconds.";
          default:
              return null;
          }
      }
  
      @Override
      public String getName() {
          return buffer.getName();
      }
  
      @Override
      public long getSizeOfData() {
          return buffer.getSize(DATA);
      }
  
      @Override
      public long getSizeOfStorage() {
          return buffer.getSize(STORAGE);
      }
  
      @Override
      public String getTimeCreatedDate() {
          final long time = buffer.getTime(CREATE);
          return UNKNOWN == time ? null : new Date(time).toString();
      }
  
      @Override
      public Long getTimeCreatedMillis() {
          final long time = buffer.getTime(CREATE);
          return UNKNOWN == time ? null : time;
      }
  
      @Override
      public String getTimeReadDate() {
         final long time = buffer.getTime(READ);
         return UNKNOWN == time ? null : new Date(time).toString();
     }
 
     @Override
     public Long getTimeReadMillis() {
         final long time = buffer.getTime(READ);
         return UNKNOWN == time ? null : time;
     }
 
     @Override
     public String getTimeWrittenDate() {
         final long time = buffer.getTime(WRITE);
         return UNKNOWN == time ? null : new Date(time).toString();
     }
 
     @Override
     public Long getTimeWrittenMillis() {
         final long time = buffer.getTime(WRITE);
         return UNKNOWN == time ? null : time;
     }
 }