1 files changed, 361 insertions, 0 deletions
diff --git a/libjava/classpath/java/nio/Buffer.java b/libjava/classpath/java/nio/Buffer.java
new file mode 100644
index 00000000000..47dabf29e42
--- /dev/null
+++ b/libjava/classpath/java/nio/Buffer.java
@@ -0,0 +1,361 @@
+/* Buffer.java -- 
+   Copyright (C) 2002, 2003, 2004  Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath 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, or (at your option)
+any later version.
+
+GNU Classpath 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 GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package java.nio;
+
+import gnu.classpath.RawData;
+
+/**
+ * @since 1.4
+ */
+public abstract class Buffer
+{
+  int cap = 0;
+  int limit = 0;
+  int pos = 0;
+  int mark = -1;
+  RawData address;
+
+  /**
+   * Creates a new Buffer.
+   *
+   * Should be package private.
+   */
+  Buffer (int capacity, int limit, int position, int mark)
+  {
+    if (capacity < 0)
+      throw new IllegalArgumentException ();
+    
+    cap = capacity;
+    limit (limit);
+    position (position);
+    
+    if (mark >= 0)
+    {
+      if (mark > pos)
+        throw new IllegalArgumentException ();
+      
+      this.mark = mark;
+    }
+  }
+  
+  /**
+   * Retrieves the capacity of the buffer.
+   *
+   * @return the capacity of the buffer
+   */
+  public final int capacity ()
+  {
+    return cap;
+  }
+
+  /**
+   * Clears the buffer.
+   *
+   * @return this buffer
+   */
+  public final Buffer clear ()
+  {
+    limit = cap;
+    pos = 0;
+    mark = -1;
+    return this;
+  }
+    
+  /**
+   * Flips the buffer.
+   *
+   * @return this buffer
+   */
+  public final Buffer flip ()
+  {
+    limit = pos;
+    pos = 0;
+    mark = -1;
+    return this;
+  }
+    
+  /**
+   * Tells whether the buffer has remaining data to read or not.
+   *
+   * @return true if the buffer contains remaining data to read,
+   * false otherwise
+   */
+  public final boolean hasRemaining ()
+  {
+    return remaining() > 0;
+  }
+
+  /**
+   * Tells whether this buffer is read only or not.
+   *
+   * @return true if the buffer is read only, false otherwise
+   */
+  public abstract boolean isReadOnly ();
+
+  /**
+   * Retrieves the current limit of the buffer.
+   *
+   * @return the limit of the buffer
+   */
+  public final int limit ()
+  {
+    return limit;
+  }
+
+  /**
+   * Sets this buffer's limit.
+   * 
+   * @param newLimit The new limit value; must be non-negative and no larger
+   * than this buffer's capacity.
+   *
+   * @return this buffer
+   *
+   * @exception IllegalArgumentException If the preconditions on newLimit
+   * do not hold.
+   */
+  public final Buffer limit (int newLimit)
+  {
+    if ((newLimit < 0) || (newLimit > cap))
+      throw new IllegalArgumentException ();
+
+    if (newLimit < mark)
+        mark = -1;
+
+    if (pos > newLimit)
+        pos = newLimit;
+
+    limit = newLimit;
+    return this;
+  }
+
+  /**
+   * Sets this buffer's mark at its position.
+   *
+   * @return this buffer
+   */
+  public final Buffer mark ()
+  {
+    mark = pos;
+    return this;
+  }
+
+  /**
+   * Retrieves the current position of this buffer.
+   *
+   * @return the current position of this buffer
+   */
+  public final int position ()
+  {
+    return pos;
+  }
+    
+  /**
+   * Sets this buffer's position. If the mark is defined and larger than the
+   * new position then it is discarded.
+   * 
+   * @param newPosition The new position value; must be non-negative and no
+   * larger than the current limit.
+   *
+   * @return this buffer
+   *
+   * @exception IllegalArgumentException If the preconditions on newPosition
+   * do not hold
+   */
+  public final Buffer position (int newPosition)
+  {
+    if ((newPosition < 0) || (newPosition > limit))
+      throw new IllegalArgumentException ();
+
+    if (newPosition <= mark)
+        mark = -1;
+
+    pos = newPosition;
+    return this;
+  }
+
+  /**
+   * Returns the number of elements between the current position and the limit.
+   *
+   * @return the number of remaining elements
+   */
+  public final int remaining()
+  {
+    return limit - pos;
+  }
+
+  /**
+   * Resets this buffer's position to the previously-marked position.
+   *
+   * @return this buffer
+   *
+   * @exception InvalidMarkException If the mark has not been set.
+   */
+  public final Buffer reset()
+  {
+    if (mark == -1)
+      throw new InvalidMarkException ();
+
+    pos = mark;
+    return this;
+  }
+
+  /**
+   * Rewinds this buffer. The position is set to zero and the mark
+   * is discarded.
+   *
+   * @return this buffer
+   */
+  public final Buffer rewind()
+  {
+    pos = 0;
+    mark = -1;
+    return this;
+  }
+
+  /**
+   * Checks for underflow. This method is used internally to check
+   * whether a buffer has enough elements left to satisfy a read 
+   * request.
+   *
+   * @exception BufferUnderflowException If there are no remaining
+   * elements in this buffer.
+   */
+  final void checkForUnderflow()
+  {
+    if (!hasRemaining())
+      throw new BufferUnderflowException();
+  }
+
+  /**
+   * Checks for underflow. This method is used internally to check
+   * whether a buffer has enough elements left to satisfy a read 
+   * request for a given number of elements.
+   *
+   * @param length The length of a sequence of elements.
+   *
+   * @exception BufferUnderflowException If there are not enough 
+   * remaining elements in this buffer.
+   */
+  final void checkForUnderflow(int length)
+  {
+    if (remaining() < length)
+      throw new BufferUnderflowException();
+  }
+
+  /**
+   * Checks for overflow. This method is used internally to check
+   * whether a buffer has enough space left to satisfy a write 
+   * request.
+   *
+   * @exception BufferOverflowException If there is no remaining
+   * space in this buffer.
+   */
+  final void checkForOverflow()
+  {
+    if (!hasRemaining())
+      throw new BufferOverflowException();
+  }
+
+  /**
+   * Checks for overflow. This method is used internally to check
+   * whether a buffer has enough space left to satisfy a write 
+   * request for a given number of elements.
+   *
+   * @param length The length of a sequence of elements.
+   *
+   * @exception BufferUnderflowException If there is not enough 
+   * remaining space in this buffer.
+   */
+  final void checkForOverflow(int length)
+  {
+    if (remaining() < length)
+      throw new BufferOverflowException();
+  }
+
+  /**
+   * Checks if index is negative or not smaller than the buffer's 
+   * limit. This method is used internally to check whether
+   * an indexed request can be fulfilled.
+   *
+   * @param index The requested position in the buffer.
+   *
+   * @exception IndexOutOfBoundsException If index is negative or not smaller
+   * than the buffer's limit.
+   */
+  final void checkIndex(int index)
+  {
+    if (index < 0
+        || index >= limit ())
+      throw new IndexOutOfBoundsException ();
+  }
+
+  /**
+   * Checks if buffer is read-only. This method is used internally to
+   * check if elements can be put into a buffer.
+   *
+   * @exception ReadOnlyBufferException If this buffer is read-only.
+   */
+  final void checkIfReadOnly() 
+  {
+    if (isReadOnly())
+      throw new ReadOnlyBufferException ();
+  }
+
+  /**
+   * Checks whether an array is large enough to hold the given number of
+   * elements at the given offset. This method is used internally to
+   * check if an array is big enough.
+   *
+   * @param arraylength The length of the array.
+   * @param offset The offset within the array of the first byte to be read;
+   * must be non-negative and no larger than arraylength.
+   * @param length The number of bytes to be read from the given array;
+   * must be non-negative and no larger than arraylength - offset.
+   *
+   * @exception IndexOutOfBoundsException If the preconditions on the offset
+   * and length parameters do not hold
+   */
+  static final void checkArraySize(int arraylength, int offset, int length)
+  {
+    if ((offset < 0) ||
+        (length < 0) ||
+        (arraylength < length + offset))
+      throw new IndexOutOfBoundsException ();
+  }
+}