--- /dev/null
+/* DoubleBuffer.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;
+
+/**
+ * @since 1.4
+ */
+public abstract class DoubleBuffer extends Buffer
+ implements Comparable
+{
+ int array_offset;
+ double[] backing_buffer;
+
+ DoubleBuffer (int capacity, int limit, int position, int mark)
+ {
+ super (capacity, limit, position, mark);
+ array_offset = 0;
+ }
+
+ /**
+ * Allocates a new <code>DoubleBuffer</code> object with a given capacity.
+ */
+ public static DoubleBuffer allocate (int capacity)
+ {
+ return new DoubleBufferImpl (capacity);
+ }
+
+ /**
+ * Wraps a <code>double</code> array into a <code>DoubleBuffer</code>
+ * object.
+ *
+ * @exception IndexOutOfBoundsException If the preconditions on the offset
+ * and length parameters do not hold
+ */
+ public static final DoubleBuffer wrap (double[] array, int offset, int length)
+ {
+ return new DoubleBufferImpl (array, 0, array.length, offset + length, offset, -1, false);
+ }
+
+ /**
+ * Wraps a <code>double</code> array into a <code>DoubleBuffer</code>
+ * object.
+ */
+ public static final DoubleBuffer wrap (double[] array)
+ {
+ return wrap (array, 0, array.length);
+ }
+
+ /**
+ * This method transfers <code>double</code>s from this buffer into the given
+ * destination array. Before the transfer, it checks if there are fewer than
+ * length <code>double</code>s remaining in this buffer.
+ *
+ * @param dst The destination array
+ * @param offset The offset within the array of the first <code>double</code>
+ * to be written; must be non-negative and no larger than dst.length.
+ * @param length The maximum number of bytes to be written to the given array;
+ * must be non-negative and no larger than dst.length - offset.
+ *
+ * @exception BufferUnderflowException If there are fewer than length
+ * <code>double</code>s remaining in this buffer.
+ * @exception IndexOutOfBoundsException If the preconditions on the offset
+ * and length parameters do not hold.
+ */
+ public DoubleBuffer get (double[] dst, int offset, int length)
+ {
+ checkArraySize(dst.length, offset, length);
+ checkForUnderflow(length);
+
+ for (int i = offset; i < offset + length; i++)
+ {
+ dst [i] = get ();
+ }
+
+ return this;
+ }
+
+ /**
+ * This method transfers <code>double</code>s from this buffer into the given
+ * destination array.
+ *
+ * @param dst The byte array to write into.
+ *
+ * @exception BufferUnderflowException If there are fewer than dst.length
+ * <code>double</code>s remaining in this buffer.
+ */
+ public DoubleBuffer get (double[] dst)
+ {
+ return get (dst, 0, dst.length);
+ }
+
+ /**
+ * Writes the content of the the <code>DoubleBUFFER</code> src
+ * into the buffer. Before the transfer, it checks if there is fewer than
+ * <code>src.remaining()</code> space remaining in this buffer.
+ *
+ * @param src The source data.
+ *
+ * @exception BufferOverflowException If there is insufficient space in this
+ * buffer for the remaining <code>double</code>s in the source buffer.
+ * @exception IllegalArgumentException If the source buffer is this buffer.
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ */
+ public DoubleBuffer put (DoubleBuffer src)
+ {
+ if (src == this)
+ throw new IllegalArgumentException ();
+
+ checkForOverflow(src.remaining ());
+
+ if (src.remaining () > 0)
+ {
+ double[] toPut = new double [src.remaining ()];
+ src.get (toPut);
+ put (toPut);
+ }
+
+ return this;
+ }
+
+ /**
+ * Writes the content of the the <code>double array</code> src
+ * into the buffer. Before the transfer, it checks if there is fewer than
+ * length space remaining in this buffer.
+ *
+ * @param src The array to copy into the buffer.
+ * @param offset The offset within the array of the first byte to be read;
+ * must be non-negative and no larger than src.length.
+ * @param length The number of bytes to be read from the given array;
+ * must be non-negative and no larger than src.length - offset.
+ *
+ * @exception BufferOverflowException If there is insufficient space in this
+ * buffer for the remaining <code>double</code>s in the source array.
+ * @exception IndexOutOfBoundsException If the preconditions on the offset
+ * and length parameters do not hold
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ */
+ public DoubleBuffer put (double[] src, int offset, int length)
+ {
+ checkArraySize(src.length, offset, length);
+ checkForOverflow(length);
+
+ for (int i = offset; i < offset + length; i++)
+ put (src [i]);
+
+ return this;
+ }
+
+ /**
+ * Writes the content of the the <code>double array</code> src
+ * into the buffer.
+ *
+ * @param src The array to copy into the buffer.
+ *
+ * @exception BufferOverflowException If there is insufficient space in this
+ * buffer for the remaining <code>double</code>s in the source array.
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ */
+ public final DoubleBuffer put (double[] src)
+ {
+ return put (src, 0, src.length);
+ }
+
+ /**
+ * Tells whether ot not this buffer is backed by an accessible
+ * <code>double</code> array.
+ */
+ public final boolean hasArray ()
+ {
+ return (backing_buffer != null
+ && !isReadOnly ());
+ }
+
+ /**
+ * Returns the <code>double</code> array that backs this buffer.
+ *
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ * @exception UnsupportedOperationException If this buffer is not backed
+ * by an accessible array.
+ */
+ public final double[] array ()
+ {
+ if (backing_buffer == null)
+ throw new UnsupportedOperationException ();
+
+ checkIfReadOnly();
+
+ return backing_buffer;
+ }
+
+ /**
+ * Returns the offset within this buffer's backing array of the first element.
+ *
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ * @exception UnsupportedOperationException If this buffer is not backed
+ * by an accessible array.
+ */
+ public final int arrayOffset ()
+ {
+ if (backing_buffer == null)
+ throw new UnsupportedOperationException ();
+
+ checkIfReadOnly();
+
+ return array_offset;
+ }
+
+ /**
+ * Calculates a hash code for this buffer.
+ *
+ * This is done with <code>long</code> arithmetic,
+ * where ** represents exponentiation, by this formula:<br>
+ * <code>s[position()] + 31 + (s[position()+1] + 30)*31**1 + ... +
+ * (s[limit()-1]+30)*31**(limit()-1)</code>.
+ * Where s is the buffer data, in Double.doubleToLongBits() form
+ * Note that the hashcode is dependent on buffer content,
+ * and therefore is not useful if the buffer content may change.
+ *
+ * @return the hash code (casted to int)
+ */
+ public int hashCode ()
+ {
+ long hashCode = Double.doubleToLongBits(get(position())) + 31;
+ long multiplier = 1;
+ for (int i = position() + 1; i < limit(); ++i)
+ {
+ multiplier *= 31;
+ hashCode += (Double.doubleToLongBits(get(i)) + 30)*multiplier;
+ }
+ return ((int)hashCode);
+ }
+
+ /**
+ * Checks if this buffer is equal to obj.
+ */
+ public boolean equals (Object obj)
+ {
+ if (obj instanceof DoubleBuffer)
+ {
+ return compareTo (obj) == 0;
+ }
+
+ return false;
+ }
+
+ /**
+ * Compares two <code>DoubleBuffer</code> objects.
+ *
+ * @exception ClassCastException If obj is not an object derived from
+ * <code>DoubleBuffer</code>.
+ */
+ public int compareTo (Object obj)
+ {
+ DoubleBuffer other = (DoubleBuffer) obj;
+
+ int num = Math.min(remaining(), other.remaining());
+ int pos_this = position();
+ int pos_other = other.position();
+
+ for (int count = 0; count < num; count++)
+ {
+ double a = get(pos_this++);
+ double b = other.get(pos_other++);
+
+ if (a == b)
+ continue;
+
+ if (a < b)
+ return -1;
+
+ return 1;
+ }
+
+ return remaining() - other.remaining();
+ }
+
+ /**
+ * Returns the byte order of this buffer.
+ */
+ public abstract ByteOrder order ();
+
+ /**
+ * Reads the <code>double</code> at this buffer's current position,
+ * and then increments the position.
+ *
+ * @exception BufferUnderflowException If there are no remaining
+ * <code>double</code>s in this buffer.
+ */
+ public abstract double get ();
+
+ /**
+ * Writes the <code>double</code> at this buffer's current position,
+ * and then increments the position.
+ *
+ * @exception BufferOverflowException If there no remaining
+ * <code>double</code>s in this buffer.
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ */
+ public abstract DoubleBuffer put (double b);
+
+ /**
+ * Absolute get method.
+ *
+ * @exception IndexOutOfBoundsException If index is negative or not smaller
+ * than the buffer's limit.
+ */
+ public abstract double get (int index);
+
+ /**
+ * Absolute put method.
+ *
+ * @exception IndexOutOfBoundsException If index is negative or not smaller
+ * than the buffer's limit.
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ */
+ public abstract DoubleBuffer put (int index, double b);
+
+ /**
+ * Compacts this buffer.
+ *
+ * @exception ReadOnlyBufferException If this buffer is read-only.
+ */
+ public abstract DoubleBuffer compact ();
+
+ /**
+ * Tells wether or not this buffer is direct.
+ */
+ public abstract boolean isDirect ();
+
+ /**
+ * Creates a new <code>DoubleBuffer</code> whose content is a shared
+ * subsequence of this buffer's content.
+ */
+ public abstract DoubleBuffer slice ();
+
+ /**
+ * Creates a new <code>DoubleBuffer</code> that shares this buffer's
+ * content.
+ */
+ public abstract DoubleBuffer duplicate ();
+
+ /**
+ * Creates a new read-only <code>DoubleBuffer</code> that shares this
+ * buffer's content.
+ */
+ public abstract DoubleBuffer asReadOnlyBuffer ();
+}
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