1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 * Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.  Oracle designates this
9 * particular file as subject to the "Classpath" exception as provided
10 * by Oracle in the LICENSE file that accompanied this code.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
23 * or visit www.oracle.com if you need additional information or have any
24 * questions.
25 */
26
27// -- This file was mechanically generated: Do not edit! -- //
28
29package java.nio;
30
31import libcore.io.Memory;
32
33/**
34 * A byte buffer.
35 *
36 * <p> This class defines six categories of operations upon
37 * byte buffers:
38 *
39 * <ul>
40 *
41 * <li><p> Absolute and relative {@link #get() </code><i>get</i><code>} and
42 * {@link #put(byte) </code><i>put</i><code>} methods that read and write
43 * single bytes; </p></li>
44 *
45 * <li><p> Relative {@link #get(byte[]) </code><i>bulk get</i><code>}
46 * methods that transfer contiguous sequences of bytes from this buffer
47 * into an array; </p></li>
48 *
49 * <li><p> Relative {@link #put(byte[]) </code><i>bulk put</i><code>}
50 * methods that transfer contiguous sequences of bytes from a
51 * byte array or some other byte
52 * buffer into this buffer; </p></li>
53 *
54 * <li><p> Absolute and relative {@link #getChar() </code><i>get</i><code>}
55 * and {@link #putChar(char) </code><i>put</i><code>} methods that read and
56 * write values of other primitive types, translating them to and from
57 * sequences of bytes in a particular byte order; </p></li>
58 *
59 * <li><p> Methods for creating <i><a href="#views">view buffers</a></i>,
60 * which allow a byte buffer to be viewed as a buffer containing values of
61 * some other primitive type; and </p></li>
62 *
63 *
64 *
65 * <li><p> Methods for {@link #compact </code>compacting<code>}, {@link
66 * #duplicate </code>duplicating<code>}, and {@link #slice
67 * </code>slicing<code>} a byte buffer.  </p></li>
68 *
69 * </ul>
70 *
71 * <p> Byte buffers can be created either by {@link #allocate
72 * </code><i>allocation</i><code>}, which allocates space for the buffer's
73 * content, or by {@link #wrap(byte[]) </code><i>wrapping</i><code>} an
74 * existing byte array  into a buffer.
75 *
76 * <a name="direct">
77 * <h4> Direct <i>vs.</i> non-direct buffers </h4>
78 *
79 * <p> A byte buffer is either <i>direct</i> or <i>non-direct</i>.  Given a
80 * direct byte buffer, the Java virtual machine will make a best effort to
81 * perform native I/O operations directly upon it.  That is, it will attempt to
82 * avoid copying the buffer's content to (or from) an intermediate buffer
83 * before (or after) each invocation of one of the underlying operating
84 * system's native I/O operations.
85 *
86 * <p> A direct byte buffer may be created by invoking the {@link
87 * #allocateDirect(int) allocateDirect} factory method of this class.  The
88 * buffers returned by this method typically have somewhat higher allocation
89 * and deallocation costs than non-direct buffers.  The contents of direct
90 * buffers may reside outside of the normal garbage-collected heap, and so
91 * their impact upon the memory footprint of an application might not be
92 * obvious.  It is therefore recommended that direct buffers be allocated
93 * primarily for large, long-lived buffers that are subject to the underlying
94 * system's native I/O operations.  In general it is best to allocate direct
95 * buffers only when they yield a measureable gain in program performance.
96 *
97 * <p> A direct byte buffer may also be created by {@link
98 * java.nio.channels.FileChannel#map </code>mapping<code>} a region of a file
99 * directly into memory.  An implementation of the Java platform may optionally
100 * support the creation of direct byte buffers from native code via JNI.  If an
101 * instance of one of these kinds of buffers refers to an inaccessible region
102 * of memory then an attempt to access that region will not change the buffer's
103 * content and will cause an unspecified exception to be thrown either at the
104 * time of the access or at some later time.
105 *
106 * <p> Whether a byte buffer is direct or non-direct may be determined by
107 * invoking its {@link #isDirect isDirect} method.  This method is provided so
108 * that explicit buffer management can be done in performance-critical code.
109 *
110 * <a name="bin">
111 * <h4> Access to binary data </h4>
112 *
113 * <p> This class defines methods for reading and writing values of all other
114 * primitive types, except <tt>boolean</tt>.  Primitive values are translated
115 * to (or from) sequences of bytes according to the buffer's current byte
116 * order, which may be retrieved and modified via the {@link #order order}
117 * methods.  Specific byte orders are represented by instances of the {@link
118 * ByteOrder} class.  The initial order of a byte buffer is always {@link
119 * ByteOrder#BIG_ENDIAN BIG_ENDIAN}.
120 *
121 * <p> For access to heterogeneous binary data, that is, sequences of values of
122 * different types, this class defines a family of absolute and relative
123 * <i>get</i> and <i>put</i> methods for each type.  For 32-bit floating-point
124 * values, for example, this class defines:
125 *
126 * <blockquote><pre>
127 * float  {@link #getFloat()}
128 * float  {@link #getFloat(int) getFloat(int index)}
129 *  void  {@link #putFloat(float) putFloat(float f)}
130 *  void  {@link #putFloat(int, float) putFloat(int index, float f)}</pre></blockquote>
131 *
132 * <p> Corresponding methods are defined for the types <tt>char</tt>,
133 * <tt>short</tt>, <tt>int</tt>, <tt>long</tt>, and <tt>double</tt>.  The index
134 * parameters of the absolute <i>get</i> and <i>put</i> methods are in terms of
135 * bytes rather than of the type being read or written.
136 *
137 * <a name="views">
138 *
139 * <p> For access to homogeneous binary data, that is, sequences of values of
140 * the same type, this class defines methods that can create <i>views</i> of a
141 * given byte buffer.  A <i>view buffer</i> is simply another buffer whose
142 * content is backed by the byte buffer.  Changes to the byte buffer's content
143 * will be visible in the view buffer, and vice versa; the two buffers'
144 * position, limit, and mark values are independent.  The {@link
145 * #asFloatBuffer() asFloatBuffer} method, for example, creates an instance of
146 * the {@link FloatBuffer} class that is backed by the byte buffer upon which
147 * the method is invoked.  Corresponding view-creation methods are defined for
148 * the types <tt>char</tt>, <tt>short</tt>, <tt>int</tt>, <tt>long</tt>, and
149 * <tt>double</tt>.
150 *
151 * <p> View buffers have three important advantages over the families of
152 * type-specific <i>get</i> and <i>put</i> methods described above:
153 *
154 * <ul>
155 *
156 * <li><p> A view buffer is indexed not in terms of bytes but rather in terms
157 * of the type-specific size of its values;  </p></li>
158 *
159 * <li><p> A view buffer provides relative bulk <i>get</i> and <i>put</i>
160 * methods that can transfer contiguous sequences of values between a buffer
161 * and an array or some other buffer of the same type; and  </p></li>
162 *
163 * <li><p> A view buffer is potentially much more efficient because it will
164 * be direct if, and only if, its backing byte buffer is direct.  </p></li>
165 *
166 * </ul>
167 *
168 * <p> The byte order of a view buffer is fixed to be that of its byte buffer
169 * at the time that the view is created.  </p>
170 *
171 * <h4> Invocation chaining </h4>
172 *
173 * <p> Methods in this class that do not otherwise have a value to return are
174 * specified to return the buffer upon which they are invoked.  This allows
175 * method invocations to be chained.
176 *
177 * The sequence of statements
178 *
179 * <blockquote><pre>
180 * bb.putInt(0xCAFEBABE);
181 * bb.putShort(3);
182 * bb.putShort(45);</pre></blockquote>
183 *
184 * can, for example, be replaced by the single statement
185 *
186 * <blockquote><pre>
187 * bb.putInt(0xCAFEBABE).putShort(3).putShort(45);</pre></blockquote>
188 *
189 * @author Mark Reinhold
190 * @author JSR-51 Expert Group
191 * @since 1.4
192 */
193
194public abstract class ByteBuffer
195        extends Buffer
196        implements Comparable<ByteBuffer> {
197
198    // These fields are declared here rather than in Heap-X-Buffer in order to
199    // reduce the number of virtual method invocations needed to access these
200    // values, which is especially costly when coding small buffers.
201    //
202    final byte[] hb;                  // Non-null only for heap buffers
203    final int offset;
204    boolean isReadOnly;                 // Valid only for heap buffers
205
206    // Creates a new buffer with the given mark, position, limit, capacity,
207    // backing array, and array offset
208    //
209    ByteBuffer(int mark, int pos, int lim, int cap,   // package-private
210               byte[] hb, int offset) {
211        super(mark, pos, lim, cap, 0);
212        this.hb = hb;
213        this.offset = offset;
214    }
215
216    // Creates a new buffer with the given mark, position, limit, and capacity
217    //
218    ByteBuffer(int mark, int pos, int lim, int cap) { // package-private
219        this(mark, pos, lim, cap, null, 0);
220    }
221
222
223    /**
224     * Allocates a new direct byte buffer.
225     *
226     * <p> The new buffer's position will be zero, its limit will be its
227     * capacity, its mark will be undefined, and each of its elements will be
228     * initialized to zero.  Whether or not it has a
229     * {@link #hasArray </code>backing array<code>} is unspecified.
230     *
231     * @param capacity The new buffer's capacity, in bytes
232     * @return The new byte buffer
233     * @throws IllegalArgumentException If the <tt>capacity</tt> is a negative integer
234     */
235    public static ByteBuffer allocateDirect(int capacity) {
236        if (capacity < 0) {
237            throw new IllegalArgumentException("capacity < 0: " + capacity);
238        }
239
240        DirectByteBuffer.MemoryRef memoryRef = new DirectByteBuffer.MemoryRef(capacity);
241        return new DirectByteBuffer(capacity, memoryRef);
242    }
243
244
245    /**
246     * Allocates a new byte buffer.
247     *
248     * <p> The new buffer's position will be zero, its limit will be its
249     * capacity, its mark will be undefined, and each of its elements will be
250     * initialized to zero.  It will have a {@link #array
251     * </code>backing array<code>}, and its {@link #arrayOffset </code>array
252     * offset<code>} will be zero.
253     *
254     * @param capacity The new buffer's capacity, in bytes
255     * @return The new byte buffer
256     * @throws IllegalArgumentException If the <tt>capacity</tt> is a negative integer
257     */
258    public static ByteBuffer allocate(int capacity) {
259        if (capacity < 0)
260            throw new IllegalArgumentException();
261        return new HeapByteBuffer(capacity, capacity);
262    }
263
264    /**
265     * Wraps a byte array into a buffer.
266     *
267     * <p> The new buffer will be backed by the given byte array;
268     * that is, modifications to the buffer will cause the array to be modified
269     * and vice versa.  The new buffer's capacity will be
270     * <tt>array.length</tt>, its position will be <tt>offset</tt>, its limit
271     * will be <tt>offset + length</tt>, and its mark will be undefined.  Its
272     * {@link #array </code>backing array<code>} will be the given array, and
273     * its {@link #arrayOffset </code>array offset<code>} will be zero.  </p>
274     *
275     * @param array  The array that will back the new buffer
276     * @param offset The offset of the subarray to be used; must be non-negative and
277     *               no larger than <tt>array.length</tt>.  The new buffer's position
278     *               will be set to this value.
279     * @param length The length of the subarray to be used;
280     *               must be non-negative and no larger than
281     *               <tt>array.length - offset</tt>.
282     *               The new buffer's limit will be set to <tt>offset + length</tt>.
283     * @return The new byte buffer
284     * @throws IndexOutOfBoundsException If the preconditions on the <tt>offset</tt> and
285     *                                   <tt>length</tt>
286     *                                   parameters do not hold
287     */
288    public static ByteBuffer wrap(byte[] array,
289                                  int offset, int length) {
290        try {
291            return new HeapByteBuffer(array, offset, length);
292        } catch (IllegalArgumentException x) {
293            throw new IndexOutOfBoundsException();
294        }
295    }
296
297    /**
298     * Wraps a byte array into a buffer.
299     *
300     * <p> The new buffer will be backed by the given byte array;
301     * that is, modifications to the buffer will cause the array to be modified
302     * and vice versa.  The new buffer's capacity and limit will be
303     * <tt>array.length</tt>, its position will be zero, and its mark will be
304     * undefined.  Its {@link #array </code>backing array<code>} will be the
305     * given array, and its {@link #arrayOffset </code>array offset<code>} will
306     * be zero.  </p>
307     *
308     * @param array The array that will back this buffer
309     * @return The new byte buffer
310     */
311    public static ByteBuffer wrap(byte[] array) {
312        return wrap(array, 0, array.length);
313    }
314
315
316    /**
317     * Creates a new byte buffer whose content is a shared subsequence of
318     * this buffer's content.
319     *
320     * <p> The content of the new buffer will start at this buffer's current
321     * position.  Changes to this buffer's content will be visible in the new
322     * buffer, and vice versa; the two buffers' position, limit, and mark
323     * values will be independent.
324     *
325     * <p> The new buffer's position will be zero, its capacity and its limit
326     * will be the number of bytes remaining in this buffer, and its mark
327     * will be undefined.  The new buffer will be direct if, and only if, this
328     * buffer is direct, and it will be read-only if, and only if, this buffer
329     * is read-only.  </p>
330     *
331     * @return The new byte buffer
332     */
333    public abstract ByteBuffer slice();
334
335    /**
336     * Creates a new byte buffer that shares this buffer's content.
337     *
338     * <p> The content of the new buffer will be that of this buffer.  Changes
339     * to this buffer's content will be visible in the new buffer, and vice
340     * versa; the two buffers' position, limit, and mark values will be
341     * independent.
342     *
343     * <p> The new buffer's capacity, limit, position, and mark values will be
344     * identical to those of this buffer.  The new buffer will be direct if,
345     * and only if, this buffer is direct, and it will be read-only if, and
346     * only if, this buffer is read-only.  </p>
347     *
348     * @return The new byte buffer
349     */
350    public abstract ByteBuffer duplicate();
351
352    /**
353     * Creates a new, read-only byte buffer that shares this buffer's
354     * content.
355     *
356     * <p> The content of the new buffer will be that of this buffer.  Changes
357     * to this buffer's content will be visible in the new buffer; the new
358     * buffer itself, however, will be read-only and will not allow the shared
359     * content to be modified.  The two buffers' position, limit, and mark
360     * values will be independent.
361     *
362     * <p> The new buffer's capacity, limit, position, and mark values will be
363     * identical to those of this buffer.
364     *
365     * <p> If this buffer is itself read-only then this method behaves in
366     * exactly the same way as the {@link #duplicate duplicate} method.  </p>
367     *
368     * @return The new, read-only byte buffer
369     */
370    public abstract ByteBuffer asReadOnlyBuffer();
371
372
373    // -- Singleton get/put methods --
374
375    /**
376     * Relative <i>get</i> method.  Reads the byte at this buffer's
377     * current position, and then increments the position. </p>
378     *
379     * @return The byte at the buffer's current position
380     * @throws BufferUnderflowException If the buffer's current position is not smaller than its
381     *                                  limit
382     */
383    public abstract byte get();
384
385    /**
386     * Relative <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
387     *
388     * <p> Writes the given byte into this buffer at the current
389     * position, and then increments the position. </p>
390     *
391     * @param b The byte to be written
392     * @return This buffer
393     * @throws BufferOverflowException If this buffer's current position is not smaller than its
394     *                                 limit
395     * @throws ReadOnlyBufferException If this buffer is read-only
396     */
397    public abstract ByteBuffer put(byte b);
398
399    /**
400     * Absolute <i>get</i> method.  Reads the byte at the given
401     * index. </p>
402     *
403     * @param index The index from which the byte will be read
404     * @return The byte at the given index
405     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
406     *                                   or not smaller than the buffer's limit
407     */
408    public abstract byte get(int index);
409
410    /**
411     * Absolute <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
412     *
413     * <p> Writes the given byte into this buffer at the given
414     * index. </p>
415     *
416     * @param index The index at which the byte will be written
417     * @param b     The byte value to be written
418     * @return This buffer
419     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
420     *                                   or not smaller than the buffer's limit
421     * @throws ReadOnlyBufferException   If this buffer is read-only
422     */
423    public abstract ByteBuffer put(int index, byte b);
424
425
426    // -- Bulk get operations --
427
428    /**
429     * Relative bulk <i>get</i> method.
430     *
431     * <p> This method transfers bytes from this buffer into the given
432     * destination array.  If there are fewer bytes remaining in the
433     * buffer than are required to satisfy the request, that is, if
434     * <tt>length</tt>&nbsp;<tt>&gt;</tt>&nbsp;<tt>remaining()</tt>, then no
435     * bytes are transferred and a {@link BufferUnderflowException} is
436     * thrown.
437     *
438     * <p> Otherwise, this method copies <tt>length</tt> bytes from this
439     * buffer into the given array, starting at the current position of this
440     * buffer and at the given offset in the array.  The position of this
441     * buffer is then incremented by <tt>length</tt>.
442     *
443     * <p> In other words, an invocation of this method of the form
444     * <tt>src.get(dst,&nbsp;off,&nbsp;len)</tt> has exactly the same effect as
445     * the loop
446     *
447     * <pre>
448     *     for (int i = off; i < off + len; i++)
449     *         dst[i] = src.get(); </pre>
450     *
451     * except that it first checks that there are sufficient bytes in
452     * this buffer and it is potentially much more efficient. </p>
453     *
454     * @param dst    The array into which bytes are to be written
455     * @param offset The offset within the array of the first byte to be
456     *               written; must be non-negative and no larger than
457     *               <tt>dst.length</tt>
458     * @param length The maximum number of bytes to be written to the given
459     *               array; must be non-negative and no larger than
460     *               <tt>dst.length - offset</tt>
461     * @return This buffer
462     * @throws BufferUnderflowException  If there are fewer than <tt>length</tt> bytes
463     *                                   remaining in this buffer
464     * @throws IndexOutOfBoundsException If the preconditions on the <tt>offset</tt> and
465     *                                   <tt>length</tt>
466     *                                   parameters do not hold
467     */
468    public ByteBuffer get(byte[] dst, int offset, int length) {
469        checkBounds(offset, length, dst.length);
470        if (length > remaining())
471            throw new BufferUnderflowException();
472        int end = offset + length;
473        for (int i = offset; i < end; i++)
474            dst[i] = get();
475        return this;
476    }
477
478    /**
479     * Relative bulk <i>get</i> method.
480     *
481     * <p> This method transfers bytes from this buffer into the given
482     * destination array.  An invocation of this method of the form
483     * <tt>src.get(a)</tt> behaves in exactly the same way as the invocation
484     *
485     * <pre>
486     *     src.get(a, 0, a.length) </pre>
487     *
488     * @return This buffer
489     * @throws BufferUnderflowException If there are fewer than <tt>length</tt> bytes
490     *                                  remaining in this buffer
491     */
492    public ByteBuffer get(byte[] dst) {
493        return get(dst, 0, dst.length);
494    }
495
496
497    // -- Bulk put operations --
498
499    /**
500     * Relative bulk <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
501     *
502     * <p> This method transfers the bytes remaining in the given source
503     * buffer into this buffer.  If there are more bytes remaining in the
504     * source buffer than in this buffer, that is, if
505     * <tt>src.remaining()</tt>&nbsp;<tt>&gt;</tt>&nbsp;<tt>remaining()</tt>,
506     * then no bytes are transferred and a {@link
507     * BufferOverflowException} is thrown.
508     *
509     * <p> Otherwise, this method copies
510     * <i>n</i>&nbsp;=&nbsp;<tt>src.remaining()</tt> bytes from the given
511     * buffer into this buffer, starting at each buffer's current position.
512     * The positions of both buffers are then incremented by <i>n</i>.
513     *
514     * <p> In other words, an invocation of this method of the form
515     * <tt>dst.put(src)</tt> has exactly the same effect as the loop
516     *
517     * <pre>
518     *     while (src.hasRemaining())
519     *         dst.put(src.get()); </pre>
520     *
521     * except that it first checks that there is sufficient space in this
522     * buffer and it is potentially much more efficient. </p>
523     *
524     * @param src The source buffer from which bytes are to be read;
525     *            must not be this buffer
526     * @return This buffer
527     * @throws BufferOverflowException  If there is insufficient space in this buffer
528     *                                  for the remaining bytes in the source buffer
529     * @throws IllegalArgumentException If the source buffer is this buffer
530     * @throws ReadOnlyBufferException  If this buffer is read-only
531     */
532    public ByteBuffer put(ByteBuffer src) {
533        if (!isAccessible()) {
534            throw new IllegalStateException("buffer is inaccessible");
535        }
536        if (isReadOnly) {
537            throw new ReadOnlyBufferException();
538        }
539        if (src == this) {
540            throw new IllegalArgumentException();
541        }
542        int n = src.remaining();
543        if (n > remaining()) {
544            throw new BufferOverflowException();
545        }
546
547        // Note that we use offset instead of arrayOffset because arrayOffset is specified to
548        // throw for read only buffers. Our use of arrayOffset here is provably safe, we only
549        // use it to read *from* readOnly buffers.
550        if (this.hb != null && src.hb != null) {
551            // System.arraycopy is intrinsified by art and therefore tiny bit faster than memmove
552            System.arraycopy(src.hb, src.position() + src.offset, hb, position() + offset, n);
553        } else {
554            // Use the buffer object (and the raw memory address) if it's a direct buffer. Note that
555            // isDirect() doesn't imply !hasArray(), ByteBuffer.allocateDirect allocated buffer will
556            // have a backing, non-gc-movable byte array. JNI allocated direct byte buffers WILL NOT
557            // have a backing array.
558            final Object srcObject = src.isDirect() ? src : src.hb;
559            int srcOffset = src.position();
560            if (!src.isDirect()) {
561                srcOffset += src.offset;
562            }
563
564            final ByteBuffer dst = this;
565            final Object dstObject = dst.isDirect() ? dst : dst.hb;
566            int dstOffset = dst.position();
567            if (!dst.isDirect()) {
568                dstOffset += dst.offset;
569            }
570            Memory.memmove(dstObject, dstOffset, srcObject, srcOffset, n);
571        }
572        src.position(src.limit());
573        this.position(this.position() + n);
574        return this;
575    }
576
577    /**
578     * Relative bulk <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
579     *
580     * <p> This method transfers bytes into this buffer from the given
581     * source array.  If there are more bytes to be copied from the array
582     * than remain in this buffer, that is, if
583     * <tt>length</tt>&nbsp;<tt>&gt;</tt>&nbsp;<tt>remaining()</tt>, then no
584     * bytes are transferred and a {@link BufferOverflowException} is
585     * thrown.
586     *
587     * <p> Otherwise, this method copies <tt>length</tt> bytes from the
588     * given array into this buffer, starting at the given offset in the array
589     * and at the current position of this buffer.  The position of this buffer
590     * is then incremented by <tt>length</tt>.
591     *
592     * <p> In other words, an invocation of this method of the form
593     * <tt>dst.put(src,&nbsp;off,&nbsp;len)</tt> has exactly the same effect as
594     * the loop
595     *
596     * <pre>
597     *     for (int i = off; i < off + len; i++)
598     *         dst.put(a[i]); </pre>
599     *
600     * except that it first checks that there is sufficient space in this
601     * buffer and it is potentially much more efficient. </p>
602     *
603     * @param src    The array from which bytes are to be read
604     * @param offset The offset within the array of the first byte to be read;
605     *               must be non-negative and no larger than <tt>array.length</tt>
606     * @param length The number of bytes to be read from the given array;
607     *               must be non-negative and no larger than
608     *               <tt>array.length - offset</tt>
609     * @return This buffer
610     * @throws BufferOverflowException   If there is insufficient space in this buffer
611     * @throws IndexOutOfBoundsException If the preconditions on the <tt>offset</tt> and
612     *                                   <tt>length</tt>
613     *                                   parameters do not hold
614     * @throws ReadOnlyBufferException   If this buffer is read-only
615     */
616    public ByteBuffer put(byte[] src, int offset, int length) {
617        checkBounds(offset, length, src.length);
618        if (length > remaining())
619            throw new BufferOverflowException();
620        int end = offset + length;
621        for (int i = offset; i < end; i++)
622            this.put(src[i]);
623        return this;
624    }
625
626    /**
627     * Relative bulk <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
628     *
629     * <p> This method transfers the entire content of the given source
630     * byte array into this buffer.  An invocation of this method of the
631     * form <tt>dst.put(a)</tt> behaves in exactly the same way as the
632     * invocation
633     *
634     * <pre>
635     *     dst.put(a, 0, a.length) </pre>
636     *
637     * @return This buffer
638     * @throws BufferOverflowException If there is insufficient space in this buffer
639     * @throws ReadOnlyBufferException If this buffer is read-only
640     */
641    public final ByteBuffer put(byte[] src) {
642        return put(src, 0, src.length);
643    }
644
645
646    // -- Other stuff --
647
648    /**
649     * Tells whether or not this buffer is backed by an accessible byte
650     * array.
651     *
652     * <p> If this method returns <tt>true</tt> then the {@link #array() array}
653     * and {@link #arrayOffset() arrayOffset} methods may safely be invoked.
654     * </p>
655     *
656     * @return <tt>true</tt> if, and only if, this buffer
657     * is backed by an array and is not read-only
658     */
659    public final boolean hasArray() {
660        return (hb != null) && !isReadOnly();
661    }
662
663    /**
664     * Returns the byte array that backs this
665     * buffer&nbsp;&nbsp;<i>(optional operation)</i>.
666     *
667     * <p> Modifications to this buffer's content will cause the returned
668     * array's content to be modified, and vice versa.
669     *
670     * <p> Invoke the {@link #hasArray hasArray} method before invoking this
671     * method in order to ensure that this buffer has an accessible backing
672     * array.  </p>
673     *
674     * @return The array that backs this buffer
675     * @throws ReadOnlyBufferException       If this buffer is backed by an array but is read-only
676     * @throws UnsupportedOperationException If this buffer is not backed by an accessible array
677     */
678    public final byte[] array() {
679        if (hb == null)
680            throw new UnsupportedOperationException();
681        if (isReadOnly)
682            throw new ReadOnlyBufferException();
683        return hb;
684    }
685
686    /**
687     * Returns the offset within this buffer's backing array of the first
688     * element of the buffer&nbsp;&nbsp;<i>(optional operation)</i>.
689     *
690     * <p> If this buffer is backed by an array then buffer position <i>p</i>
691     * corresponds to array index <i>p</i>&nbsp;+&nbsp;<tt>arrayOffset()</tt>.
692     *
693     * <p> Invoke the {@link #hasArray hasArray} method before invoking this
694     * method in order to ensure that this buffer has an accessible backing
695     * array.  </p>
696     *
697     * @return The offset within this buffer's array
698     * of the first element of the buffer
699     * @throws ReadOnlyBufferException       If this buffer is backed by an array but is read-only
700     * @throws UnsupportedOperationException If this buffer is not backed by an accessible array
701     */
702    public final int arrayOffset() {
703        if (hb == null)
704            throw new UnsupportedOperationException();
705        if (isReadOnly)
706            throw new ReadOnlyBufferException();
707        return offset;
708    }
709
710    /**
711     * Compacts this buffer&nbsp;&nbsp;<i>(optional operation)</i>.
712     *
713     * <p> The bytes between the buffer's current position and its limit,
714     * if any, are copied to the beginning of the buffer.  That is, the
715     * byte at index <i>p</i>&nbsp;=&nbsp;<tt>position()</tt> is copied
716     * to index zero, the byte at index <i>p</i>&nbsp;+&nbsp;1 is copied
717     * to index one, and so forth until the byte at index
718     * <tt>limit()</tt>&nbsp;-&nbsp;1 is copied to index
719     * <i>n</i>&nbsp;=&nbsp;<tt>limit()</tt>&nbsp;-&nbsp;<tt>1</tt>&nbsp;-&nbsp;<i>p</i>.
720     * The buffer's position is then set to <i>n+1</i> and its limit is set to
721     * its capacity.  The mark, if defined, is discarded.
722     *
723     * <p> The buffer's position is set to the number of bytes copied,
724     * rather than to zero, so that an invocation of this method can be
725     * followed immediately by an invocation of another relative <i>put</i>
726     * method. </p>
727     *
728     *
729     *
730     * <p> Invoke this method after writing data from a buffer in case the
731     * write was incomplete.  The following loop, for example, copies bytes
732     * from one channel to another via the buffer <tt>buf</tt>:
733     *
734     * <blockquote><pre>
735     * buf.clear();          // Prepare buffer for use
736     * while (in.read(buf) >= 0 || buf.position != 0) {
737     *     buf.flip();
738     *     out.write(buf);
739     *     buf.compact();    // In case of partial write
740     * }</pre></blockquote>
741     *
742     * @return This buffer
743     * @throws ReadOnlyBufferException If this buffer is read-only
744     */
745    public abstract ByteBuffer compact();
746
747    /**
748     * Tells whether or not this byte buffer is direct. </p>
749     *
750     * @return <tt>true</tt> if, and only if, this buffer is direct
751     */
752    public abstract boolean isDirect();
753
754
755    /**
756     * Returns a string summarizing the state of this buffer.  </p>
757     *
758     * @return A summary string
759     */
760    public String toString() {
761        StringBuffer sb = new StringBuffer();
762        sb.append(getClass().getName());
763        sb.append("[pos=");
764        sb.append(position());
765        sb.append(" lim=");
766        sb.append(limit());
767        sb.append(" cap=");
768        sb.append(capacity());
769        sb.append("]");
770        return sb.toString();
771    }
772
773
774    /**
775     * Returns the current hash code of this buffer.
776     *
777     * <p> The hash code of a byte buffer depends only upon its remaining
778     * elements; that is, upon the elements from <tt>position()</tt> up to, and
779     * including, the element at <tt>limit()</tt>&nbsp;-&nbsp;<tt>1</tt>.
780     *
781     * <p> Because buffer hash codes are content-dependent, it is inadvisable
782     * to use buffers as keys in hash maps or similar data structures unless it
783     * is known that their contents will not change.  </p>
784     *
785     * @return The current hash code of this buffer
786     */
787    public int hashCode() {
788        int h = 1;
789        int p = position();
790        for (int i = limit() - 1; i >= p; i--)
791            h = 31 * h + (int) get(i);
792        return h;
793    }
794
795    /**
796     * Tells whether or not this buffer is equal to another object.
797     *
798     * <p> Two byte buffers are equal if, and only if,
799     *
800     * <p><ol>
801     *
802     * <li><p> They have the same element type,  </p></li>
803     *
804     * <li><p> They have the same number of remaining elements, and
805     * </p></li>
806     *
807     * <li><p> The two sequences of remaining elements, considered
808     * independently of their starting positions, are pointwise equal.
809     *
810     *
811     *
812     *
813     *
814     *
815     *
816     * </p></li>
817     *
818     * </ol>
819     *
820     * <p> A byte buffer is not equal to any other type of object.  </p>
821     *
822     * @param ob The object to which this buffer is to be compared
823     * @return <tt>true</tt> if, and only if, this buffer is equal to the
824     * given object
825     */
826    public boolean equals(Object ob) {
827        if (this == ob)
828            return true;
829        if (!(ob instanceof ByteBuffer))
830            return false;
831        ByteBuffer that = (ByteBuffer) ob;
832        if (this.remaining() != that.remaining())
833            return false;
834        int p = this.position();
835        for (int i = this.limit() - 1, j = that.limit() - 1; i >= p; i--, j--)
836            if (!equals(this.get(i), that.get(j)))
837                return false;
838        return true;
839    }
840
841    private static boolean equals(byte x, byte y) {
842
843
844        return x == y;
845
846    }
847
848    /**
849     * Compares this buffer to another.
850     *
851     * <p> Two byte buffers are compared by comparing their sequences of
852     * remaining elements lexicographically, without regard to the starting
853     * position of each sequence within its corresponding buffer.
854     *
855     *
856     *
857     *
858     *
859     *
860     *
861     *
862     * Pairs of {@code byte} elements are compared as if by invoking
863     * {@link Byte#compare(byte, byte)}.
864     *
865     *
866     * <p> A byte buffer is not comparable to any other type of object.
867     *
868     * @return A negative integer, zero, or a positive integer as this buffer
869     * is less than, equal to, or greater than the given buffer
870     */
871    public int compareTo(ByteBuffer that) {
872        int n = this.position() + Math.min(this.remaining(), that.remaining());
873        for (int i = this.position(), j = that.position(); i < n; i++, j++) {
874            int cmp = compare(this.get(i), that.get(j));
875            if (cmp != 0)
876                return cmp;
877        }
878        return this.remaining() - that.remaining();
879    }
880
881    private static int compare(byte x, byte y) {
882
883
884        return Byte.compare(x, y);
885
886    }
887
888    // -- Other char stuff --
889
890
891    // -- Other byte stuff: Access to binary data --
892
893
894    boolean bigEndian                                   // package-private
895            = true;
896    boolean nativeByteOrder                             // package-private
897            = (Bits.byteOrder() == ByteOrder.BIG_ENDIAN);
898
899    /**
900     * Retrieves this buffer's byte order.
901     *
902     * <p> The byte order is used when reading or writing multibyte values, and
903     * when creating buffers that are views of this byte buffer.  The order of
904     * a newly-created byte buffer is always {@link ByteOrder#BIG_ENDIAN
905     * BIG_ENDIAN}.  </p>
906     *
907     * @return This buffer's byte order
908     */
909    public final ByteOrder order() {
910        return bigEndian ? ByteOrder.BIG_ENDIAN : ByteOrder.LITTLE_ENDIAN;
911    }
912
913    /**
914     * Modifies this buffer's byte order.  </p>
915     *
916     * @param bo The new byte order,
917     *           either {@link ByteOrder#BIG_ENDIAN BIG_ENDIAN}
918     *           or {@link ByteOrder#LITTLE_ENDIAN LITTLE_ENDIAN}
919     * @return This buffer
920     */
921    public final ByteBuffer order(ByteOrder bo) {
922        bigEndian = (bo == ByteOrder.BIG_ENDIAN);
923        nativeByteOrder =
924                (bigEndian == (Bits.byteOrder() == ByteOrder.BIG_ENDIAN));
925        return this;
926    }
927
928    // Unchecked accessors, for use by ByteBufferAs-X-Buffer classes
929    //
930    abstract byte _get(int i);                          // package-private
931
932    abstract void _put(int i, byte b);                  // package-private
933
934
935    /**
936     * Relative <i>get</i> method for reading a char value.
937     *
938     * <p> Reads the next two bytes at this buffer's current position,
939     * composing them into a char value according to the current byte order,
940     * and then increments the position by two.  </p>
941     *
942     * @return The char value at the buffer's current position
943     * @throws BufferUnderflowException If there are fewer than two bytes
944     *                                  remaining in this buffer
945     */
946    public abstract char getChar();
947
948    /**
949     * Relative <i>put</i> method for writing a char
950     * value&nbsp;&nbsp;<i>(optional operation)</i>.
951     *
952     * <p> Writes two bytes containing the given char value, in the
953     * current byte order, into this buffer at the current position, and then
954     * increments the position by two.  </p>
955     *
956     * @param value The char value to be written
957     * @return This buffer
958     * @throws BufferOverflowException If there are fewer than two bytes
959     *                                 remaining in this buffer
960     * @throws ReadOnlyBufferException If this buffer is read-only
961     */
962    public abstract ByteBuffer putChar(char value);
963
964    /**
965     * Absolute <i>get</i> method for reading a char value.
966     *
967     * <p> Reads two bytes at the given index, composing them into a
968     * char value according to the current byte order.  </p>
969     *
970     * @param index The index from which the bytes will be read
971     * @return The char value at the given index
972     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
973     *                                   or not smaller than the buffer's limit,
974     *                                   minus one
975     */
976    public abstract char getChar(int index);
977
978    char getCharUnchecked(int index) {
979        throw new UnsupportedOperationException();
980    }
981
982    void getUnchecked(int pos, char[] dst, int dstOffset, int length) {
983        throw new UnsupportedOperationException();
984    }
985
986    /**
987     * Absolute <i>put</i> method for writing a char
988     * value&nbsp;&nbsp;<i>(optional operation)</i>.
989     *
990     * <p> Writes two bytes containing the given char value, in the
991     * current byte order, into this buffer at the given index.  </p>
992     *
993     * @param index The index at which the bytes will be written
994     * @param value The char value to be written
995     * @return This buffer
996     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
997     *                                   or not smaller than the buffer's limit,
998     *                                   minus one
999     * @throws ReadOnlyBufferException   If this buffer is read-only
1000     */
1001    public abstract ByteBuffer putChar(int index, char value);
1002
1003    void putCharUnchecked(int index, char value) {
1004        throw new UnsupportedOperationException();
1005    }
1006
1007    void putUnchecked(int pos, char[] dst, int srcOffset, int length) {
1008        throw new UnsupportedOperationException();
1009    }
1010
1011    /**
1012     * Creates a view of this byte buffer as a char buffer.
1013     *
1014     * <p> The content of the new buffer will start at this buffer's current
1015     * position.  Changes to this buffer's content will be visible in the new
1016     * buffer, and vice versa; the two buffers' position, limit, and mark
1017     * values will be independent.
1018     *
1019     * <p> The new buffer's position will be zero, its capacity and its limit
1020     * will be the number of bytes remaining in this buffer divided by
1021     * two, and its mark will be undefined.  The new buffer will be direct
1022     * if, and only if, this buffer is direct, and it will be read-only if, and
1023     * only if, this buffer is read-only.  </p>
1024     *
1025     * @return A new char buffer
1026     */
1027    public abstract CharBuffer asCharBuffer();
1028
1029
1030    /**
1031     * Relative <i>get</i> method for reading a short value.
1032     *
1033     * <p> Reads the next two bytes at this buffer's current position,
1034     * composing them into a short value according to the current byte order,
1035     * and then increments the position by two.  </p>
1036     *
1037     * @return The short value at the buffer's current position
1038     * @throws BufferUnderflowException If there are fewer than two bytes
1039     *                                  remaining in this buffer
1040     */
1041    public abstract short getShort();
1042
1043    /**
1044     * Relative <i>put</i> method for writing a short
1045     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1046     *
1047     * <p> Writes two bytes containing the given short value, in the
1048     * current byte order, into this buffer at the current position, and then
1049     * increments the position by two.  </p>
1050     *
1051     * @param value The short value to be written
1052     * @return This buffer
1053     * @throws BufferOverflowException If there are fewer than two bytes
1054     *                                 remaining in this buffer
1055     * @throws ReadOnlyBufferException If this buffer is read-only
1056     */
1057    public abstract ByteBuffer putShort(short value);
1058
1059    /**
1060     * Absolute <i>get</i> method for reading a short value.
1061     *
1062     * <p> Reads two bytes at the given index, composing them into a
1063     * short value according to the current byte order.  </p>
1064     *
1065     * @param index The index from which the bytes will be read
1066     * @return The short value at the given index
1067     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1068     *                                   or not smaller than the buffer's limit,
1069     *                                   minus one
1070     */
1071    public abstract short getShort(int index);
1072
1073    short getShortUnchecked(int index) {
1074        throw new UnsupportedOperationException();
1075    }
1076
1077    void getUnchecked(int pos, short[] dst, int dstOffset, int length) {
1078        throw new UnsupportedOperationException();
1079    }
1080
1081    /**
1082     * Absolute <i>put</i> method for writing a short
1083     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1084     *
1085     * <p> Writes two bytes containing the given short value, in the
1086     * current byte order, into this buffer at the given index.  </p>
1087     *
1088     * @param index The index at which the bytes will be written
1089     * @param value The short value to be written
1090     * @return This buffer
1091     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1092     *                                   or not smaller than the buffer's limit,
1093     *                                   minus one
1094     * @throws ReadOnlyBufferException   If this buffer is read-only
1095     */
1096    public abstract ByteBuffer putShort(int index, short value);
1097
1098    void putShortUnchecked(int index, short value) {
1099        throw new UnsupportedOperationException();
1100    }
1101
1102    void putUnchecked(int pos, short[] dst, int srcOffset, int length) {
1103        throw new UnsupportedOperationException();
1104    }
1105
1106    /**
1107     * Creates a view of this byte buffer as a short buffer.
1108     *
1109     * <p> The content of the new buffer will start at this buffer's current
1110     * position.  Changes to this buffer's content will be visible in the new
1111     * buffer, and vice versa; the two buffers' position, limit, and mark
1112     * values will be independent.
1113     *
1114     * <p> The new buffer's position will be zero, its capacity and its limit
1115     * will be the number of bytes remaining in this buffer divided by
1116     * two, and its mark will be undefined.  The new buffer will be direct
1117     * if, and only if, this buffer is direct, and it will be read-only if, and
1118     * only if, this buffer is read-only.  </p>
1119     *
1120     * @return A new short buffer
1121     */
1122    public abstract ShortBuffer asShortBuffer();
1123
1124
1125    /**
1126     * Relative <i>get</i> method for reading an int value.
1127     *
1128     * <p> Reads the next four bytes at this buffer's current position,
1129     * composing them into an int value according to the current byte order,
1130     * and then increments the position by four.  </p>
1131     *
1132     * @return The int value at the buffer's current position
1133     * @throws BufferUnderflowException If there are fewer than four bytes
1134     *                                  remaining in this buffer
1135     */
1136    public abstract int getInt();
1137
1138    /**
1139     * Relative <i>put</i> method for writing an int
1140     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1141     *
1142     * <p> Writes four bytes containing the given int value, in the
1143     * current byte order, into this buffer at the current position, and then
1144     * increments the position by four.  </p>
1145     *
1146     * @param value The int value to be written
1147     * @return This buffer
1148     * @throws BufferOverflowException If there are fewer than four bytes
1149     *                                 remaining in this buffer
1150     * @throws ReadOnlyBufferException If this buffer is read-only
1151     */
1152    public abstract ByteBuffer putInt(int value);
1153
1154    /**
1155     * Absolute <i>get</i> method for reading an int value.
1156     *
1157     * <p> Reads four bytes at the given index, composing them into a
1158     * int value according to the current byte order.  </p>
1159     *
1160     * @param index The index from which the bytes will be read
1161     * @return The int value at the given index
1162     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1163     *                                   or not smaller than the buffer's limit,
1164     *                                   minus three
1165     */
1166    public abstract int getInt(int index);
1167
1168    int getIntUnchecked(int index) {
1169        throw new UnsupportedOperationException();
1170    }
1171
1172    void getUnchecked(int pos, int[] dst, int dstOffset, int length) {
1173        throw new UnsupportedOperationException();
1174    }
1175
1176    /**
1177     * Absolute <i>put</i> method for writing an int
1178     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1179     *
1180     * <p> Writes four bytes containing the given int value, in the
1181     * current byte order, into this buffer at the given index.  </p>
1182     *
1183     * @param index The index at which the bytes will be written
1184     * @param value The int value to be written
1185     * @return This buffer
1186     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1187     *                                   or not smaller than the buffer's limit,
1188     *                                   minus three
1189     * @throws ReadOnlyBufferException   If this buffer is read-only
1190     */
1191    public abstract ByteBuffer putInt(int index, int value);
1192
1193    void putIntUnchecked(int index, int value) {
1194        throw new UnsupportedOperationException();
1195    }
1196
1197    void putUnchecked(int pos, int[] dst, int srcOffset, int length) {
1198        throw new UnsupportedOperationException();
1199    }
1200
1201    /**
1202     * Creates a view of this byte buffer as an int buffer.
1203     *
1204     * <p> The content of the new buffer will start at this buffer's current
1205     * position.  Changes to this buffer's content will be visible in the new
1206     * buffer, and vice versa; the two buffers' position, limit, and mark
1207     * values will be independent.
1208     *
1209     * <p> The new buffer's position will be zero, its capacity and its limit
1210     * will be the number of bytes remaining in this buffer divided by
1211     * four, and its mark will be undefined.  The new buffer will be direct
1212     * if, and only if, this buffer is direct, and it will be read-only if, and
1213     * only if, this buffer is read-only.  </p>
1214     *
1215     * @return A new int buffer
1216     */
1217    public abstract IntBuffer asIntBuffer();
1218
1219
1220    /**
1221     * Relative <i>get</i> method for reading a long value.
1222     *
1223     * <p> Reads the next eight bytes at this buffer's current position,
1224     * composing them into a long value according to the current byte order,
1225     * and then increments the position by eight.  </p>
1226     *
1227     * @return The long value at the buffer's current position
1228     * @throws BufferUnderflowException If there are fewer than eight bytes
1229     *                                  remaining in this buffer
1230     */
1231    public abstract long getLong();
1232
1233    /**
1234     * Relative <i>put</i> method for writing a long
1235     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1236     *
1237     * <p> Writes eight bytes containing the given long value, in the
1238     * current byte order, into this buffer at the current position, and then
1239     * increments the position by eight.  </p>
1240     *
1241     * @param value The long value to be written
1242     * @return This buffer
1243     * @throws BufferOverflowException If there are fewer than eight bytes
1244     *                                 remaining in this buffer
1245     * @throws ReadOnlyBufferException If this buffer is read-only
1246     */
1247    public abstract ByteBuffer putLong(long value);
1248
1249    /**
1250     * Absolute <i>get</i> method for reading a long value.
1251     *
1252     * <p> Reads eight bytes at the given index, composing them into a
1253     * long value according to the current byte order.  </p>
1254     *
1255     * @param index The index from which the bytes will be read
1256     * @return The long value at the given index
1257     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1258     *                                   or not smaller than the buffer's limit,
1259     *                                   minus seven
1260     */
1261    public abstract long getLong(int index);
1262
1263    long getLongUnchecked(int index) {
1264        throw new UnsupportedOperationException();
1265    }
1266
1267    void getUnchecked(int pos, long[] dst, int dstOffset, int length) {
1268        throw new UnsupportedOperationException();
1269    }
1270
1271    /**
1272     * Absolute <i>put</i> method for writing a long
1273     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1274     *
1275     * <p> Writes eight bytes containing the given long value, in the
1276     * current byte order, into this buffer at the given index.  </p>
1277     *
1278     * @param index The index at which the bytes will be written
1279     * @param value The long value to be written
1280     * @return This buffer
1281     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1282     *                                   or not smaller than the buffer's limit,
1283     *                                   minus seven
1284     * @throws ReadOnlyBufferException   If this buffer is read-only
1285     */
1286    public abstract ByteBuffer putLong(int index, long value);
1287
1288    void putLongUnchecked(int index, long value) {
1289        throw new UnsupportedOperationException();
1290    }
1291
1292    void putUnchecked(int pos, long[] dst, int srcOffset, int length) {
1293        throw new UnsupportedOperationException();
1294    }
1295
1296    /**
1297     * Creates a view of this byte buffer as a long buffer.
1298     *
1299     * <p> The content of the new buffer will start at this buffer's current
1300     * position.  Changes to this buffer's content will be visible in the new
1301     * buffer, and vice versa; the two buffers' position, limit, and mark
1302     * values will be independent.
1303     *
1304     * <p> The new buffer's position will be zero, its capacity and its limit
1305     * will be the number of bytes remaining in this buffer divided by
1306     * eight, and its mark will be undefined.  The new buffer will be direct
1307     * if, and only if, this buffer is direct, and it will be read-only if, and
1308     * only if, this buffer is read-only.  </p>
1309     *
1310     * @return A new long buffer
1311     */
1312    public abstract LongBuffer asLongBuffer();
1313
1314
1315    /**
1316     * Relative <i>get</i> method for reading a float value.
1317     *
1318     * <p> Reads the next four bytes at this buffer's current position,
1319     * composing them into a float value according to the current byte order,
1320     * and then increments the position by four.  </p>
1321     *
1322     * @return The float value at the buffer's current position
1323     * @throws BufferUnderflowException If there are fewer than four bytes
1324     *                                  remaining in this buffer
1325     */
1326    public abstract float getFloat();
1327
1328    /**
1329     * Relative <i>put</i> method for writing a float
1330     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1331     *
1332     * <p> Writes four bytes containing the given float value, in the
1333     * current byte order, into this buffer at the current position, and then
1334     * increments the position by four.  </p>
1335     *
1336     * @param value The float value to be written
1337     * @return This buffer
1338     * @throws BufferOverflowException If there are fewer than four bytes
1339     *                                 remaining in this buffer
1340     * @throws ReadOnlyBufferException If this buffer is read-only
1341     */
1342    public abstract ByteBuffer putFloat(float value);
1343
1344    /**
1345     * Absolute <i>get</i> method for reading a float value.
1346     *
1347     * <p> Reads four bytes at the given index, composing them into a
1348     * float value according to the current byte order.  </p>
1349     *
1350     * @param index The index from which the bytes will be read
1351     * @return The float value at the given index
1352     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1353     *                                   or not smaller than the buffer's limit,
1354     *                                   minus three
1355     */
1356    public abstract float getFloat(int index);
1357
1358    float getFloatUnchecked(int index) {
1359        throw new UnsupportedOperationException();
1360    }
1361
1362    void getUnchecked(int pos, float[] dst, int dstOffset, int length) {
1363        throw new UnsupportedOperationException();
1364    }
1365
1366    /**
1367     * Absolute <i>put</i> method for writing a float
1368     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1369     *
1370     * <p> Writes four bytes containing the given float value, in the
1371     * current byte order, into this buffer at the given index.  </p>
1372     *
1373     * @param index The index at which the bytes will be written
1374     * @param value The float value to be written
1375     * @return This buffer
1376     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1377     *                                   or not smaller than the buffer's limit,
1378     *                                   minus three
1379     * @throws ReadOnlyBufferException   If this buffer is read-only
1380     */
1381    public abstract ByteBuffer putFloat(int index, float value);
1382
1383    void putFloatUnchecked(int index, float value) {
1384        throw new UnsupportedOperationException();
1385    }
1386
1387    void putUnchecked(int pos, float[] dst, int srcOffset, int length) {
1388        throw new UnsupportedOperationException();
1389    }
1390
1391    /**
1392     * Creates a view of this byte buffer as a float buffer.
1393     *
1394     * <p> The content of the new buffer will start at this buffer's current
1395     * position.  Changes to this buffer's content will be visible in the new
1396     * buffer, and vice versa; the two buffers' position, limit, and mark
1397     * values will be independent.
1398     *
1399     * <p> The new buffer's position will be zero, its capacity and its limit
1400     * will be the number of bytes remaining in this buffer divided by
1401     * four, and its mark will be undefined.  The new buffer will be direct
1402     * if, and only if, this buffer is direct, and it will be read-only if, and
1403     * only if, this buffer is read-only.  </p>
1404     *
1405     * @return A new float buffer
1406     */
1407    public abstract FloatBuffer asFloatBuffer();
1408
1409
1410    /**
1411     * Relative <i>get</i> method for reading a double value.
1412     *
1413     * <p> Reads the next eight bytes at this buffer's current position,
1414     * composing them into a double value according to the current byte order,
1415     * and then increments the position by eight.  </p>
1416     *
1417     * @return The double value at the buffer's current position
1418     * @throws BufferUnderflowException If there are fewer than eight bytes
1419     *                                  remaining in this buffer
1420     */
1421    public abstract double getDouble();
1422
1423    /**
1424     * Relative <i>put</i> method for writing a double
1425     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1426     *
1427     * <p> Writes eight bytes containing the given double value, in the
1428     * current byte order, into this buffer at the current position, and then
1429     * increments the position by eight.  </p>
1430     *
1431     * @param value The double value to be written
1432     * @return This buffer
1433     * @throws BufferOverflowException If there are fewer than eight bytes
1434     *                                 remaining in this buffer
1435     * @throws ReadOnlyBufferException If this buffer is read-only
1436     */
1437    public abstract ByteBuffer putDouble(double value);
1438
1439    /**
1440     * Absolute <i>get</i> method for reading a double value.
1441     *
1442     * <p> Reads eight bytes at the given index, composing them into a
1443     * double value according to the current byte order.  </p>
1444     *
1445     * @param index The index from which the bytes will be read
1446     * @return The double value at the given index
1447     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1448     *                                   or not smaller than the buffer's limit,
1449     *                                   minus seven
1450     */
1451    public abstract double getDouble(int index);
1452
1453    double getDoubleUnchecked(int index) {
1454        throw new UnsupportedOperationException();
1455    }
1456
1457    void getUnchecked(int pos, double[] dst, int dstOffset, int length) {
1458        throw new UnsupportedOperationException();
1459    }
1460
1461    /**
1462     * Absolute <i>put</i> method for writing a double
1463     * value&nbsp;&nbsp;<i>(optional operation)</i>.
1464     *
1465     * <p> Writes eight bytes containing the given double value, in the
1466     * current byte order, into this buffer at the given index.  </p>
1467     *
1468     * @param index The index at which the bytes will be written
1469     * @param value The double value to be written
1470     * @return This buffer
1471     * @throws IndexOutOfBoundsException If <tt>index</tt> is negative
1472     *                                   or not smaller than the buffer's limit,
1473     *                                   minus seven
1474     * @throws ReadOnlyBufferException   If this buffer is read-only
1475     */
1476    public abstract ByteBuffer putDouble(int index, double value);
1477
1478    void putDoubleUnchecked(int index, double value) {
1479        throw new UnsupportedOperationException();
1480    }
1481
1482    void putUnchecked(int pos, double[] dst, int srcOffset, int length) {
1483        throw new UnsupportedOperationException();
1484    }
1485
1486    /**
1487     * Creates a view of this byte buffer as a double buffer.
1488     *
1489     * <p> The content of the new buffer will start at this buffer's current
1490     * position.  Changes to this buffer's content will be visible in the new
1491     * buffer, and vice versa; the two buffers' position, limit, and mark
1492     * values will be independent.
1493     *
1494     * <p> The new buffer's position will be zero, its capacity and its limit
1495     * will be the number of bytes remaining in this buffer divided by
1496     * eight, and its mark will be undefined.  The new buffer will be direct
1497     * if, and only if, this buffer is direct, and it will be read-only if, and
1498     * only if, this buffer is read-only.  </p>
1499     *
1500     * @return A new double buffer
1501     */
1502    public abstract DoubleBuffer asDoubleBuffer();
1503
1504    /**
1505     * @hide
1506     */
1507    public boolean isAccessible() {
1508        return true;
1509    }
1510
1511    /**
1512     * @hide
1513     */
1514    public void setAccessible(boolean value) {
1515        throw new UnsupportedOperationException();
1516    }
1517}
1518