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/*
* Copyright (C) 2014 The Android Open Source Project
* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
// -- This file was mechanically generated: Do not edit! -- //
package java.nio;
import libcore.io.Memory;
/**
* A byte buffer.
*
* This class defines six categories of operations upon
* byte buffers:
*
*
*
* Absolute and relative {@link #get() get} and
* {@link #put(byte) put} methods that read and write
* single bytes;
*
* Relative {@link #get(byte[]) bulk get}
* methods that transfer contiguous sequences of bytes from this buffer
* into an array;
*
* Relative {@link #put(byte[]) bulk put}
* methods that transfer contiguous sequences of bytes from a
* byte array or some other byte
* buffer into this buffer;
*
*
* Absolute and relative {@link #getChar() get}
* and {@link #putChar(char) put} methods that read and
* write values of other primitive types, translating them to and from
* sequences of bytes in a particular byte order;
*
* Methods for creating view buffers,
* which allow a byte buffer to be viewed as a buffer containing values of
* some other primitive type; and
*
*
* Methods for {@link #compact compacting}, {@link
* #duplicate duplicating}, and {@link #slice slicing}
* a byte buffer.
*
*
*
* Byte buffers can be created either by {@link #allocate
* allocation}, which allocates space for the buffer's
*
*
* content, or by {@link #wrap(byte[]) wrapping} an
* existing byte array into a buffer.
*
*
*
*
*
Direct vs. non-direct buffers
*
* A byte buffer is either direct or non-direct. Given a
* direct byte buffer, the Java virtual machine will make a best effort to
* perform native I/O operations directly upon it. That is, it will attempt to
* avoid copying the buffer's content to (or from) an intermediate buffer
* before (or after) each invocation of one of the underlying operating
* system's native I/O operations.
*
*
A direct byte buffer may be created by invoking the {@link
* #allocateDirect(int) allocateDirect} factory method of this class. The
* buffers returned by this method typically have somewhat higher allocation
* and deallocation costs than non-direct buffers. The contents of direct
* buffers may reside outside of the normal garbage-collected heap, and so
* their impact upon the memory footprint of an application might not be
* obvious. It is therefore recommended that direct buffers be allocated
* primarily for large, long-lived buffers that are subject to the underlying
* system's native I/O operations. In general it is best to allocate direct
* buffers only when they yield a measureable gain in program performance.
*
*
A direct byte buffer may also be created by {@link
* java.nio.channels.FileChannel#map mapping} a region of a file
* directly into memory. An implementation of the Java platform may optionally
* support the creation of direct byte buffers from native code via JNI. If an
* instance of one of these kinds of buffers refers to an inaccessible region
* of memory then an attempt to access that region will not change the buffer's
* content and will cause an unspecified exception to be thrown either at the
* time of the access or at some later time.
*
*
Whether a byte buffer is direct or non-direct may be determined by
* invoking its {@link #isDirect isDirect} method. This method is provided so
* that explicit buffer management can be done in performance-critical code.
*
*
*
*
Access to binary data
*
* This class defines methods for reading and writing values of all other
* primitive types, except boolean. Primitive values are translated
* to (or from) sequences of bytes according to the buffer's current byte
* order, which may be retrieved and modified via the {@link #order order}
* methods. Specific byte orders are represented by instances of the {@link
* ByteOrder} class. The initial order of a byte buffer is always {@link
* ByteOrder#BIG_ENDIAN BIG_ENDIAN}.
*
*
For access to heterogeneous binary data, that is, sequences of values of
* different types, this class defines a family of absolute and relative
* get and put methods for each type. For 32-bit floating-point
* values, for example, this class defines:
*
*
* float {@link #getFloat()}
* float {@link #getFloat(int) getFloat(int index)}
* void {@link #putFloat(float) putFloat(float f)}
* void {@link #putFloat(int,float) putFloat(int index, float f)}
*
* Corresponding methods are defined for the types char,
* short, int, long, and double. The index
* parameters of the absolute get and put methods are in terms of
* bytes rather than of the type being read or written.
*
*
*
*
For access to homogeneous binary data, that is, sequences of values of
* the same type, this class defines methods that can create views of a
* given byte buffer. A view buffer is simply another buffer whose
* content is backed by the byte buffer. Changes to the byte buffer's content
* will be visible in the view buffer, and vice versa; the two buffers'
* position, limit, and mark values are independent. The {@link
* #asFloatBuffer() asFloatBuffer} method, for example, creates an instance of
* the {@link FloatBuffer} class that is backed by the byte buffer upon which
* the method is invoked. Corresponding view-creation methods are defined for
* the types char, short, int, long, and
* double.
*
*
View buffers have three important advantages over the families of
* type-specific get and put methods described above:
*
*
*
* A view buffer is indexed not in terms of bytes but rather in terms
* of the type-specific size of its values;
*
* A view buffer provides relative bulk get and put
* methods that can transfer contiguous sequences of values between a buffer
* and an array or some other buffer of the same type; and
*
* A view buffer is potentially much more efficient because it will
* be direct if, and only if, its backing byte buffer is direct.
*
*
*
* The byte order of a view buffer is fixed to be that of its byte buffer
* at the time that the view is created.
*
*
*
*
* Invocation chaining
*
* Methods in this class that do not otherwise have a value to return are
* specified to return the buffer upon which they are invoked. This allows
* method invocations to be chained.
*
*
* The sequence of statements
*
*
* bb.putInt(0xCAFEBABE);
* bb.putShort(3);
* bb.putShort(45);
*
* can, for example, be replaced by the single statement
*
*
* bb.putInt(0xCAFEBABE).putShort(3).putShort(45);
*
*
*
* @author Mark Reinhold
* @author JSR-51 Expert Group
* @since 1.4
*/
public abstract class ByteBuffer
extends Buffer
implements Comparable
{
// These fields are declared here rather than in Heap-X-Buffer in order to
// reduce the number of virtual method invocations needed to access these
// values, which is especially costly when coding small buffers.
//
final byte[] hb; // Non-null only for heap buffers
final int offset;
boolean isReadOnly; // Valid only for heap buffers
// Creates a new buffer with the given mark, position, limit, capacity,
// backing array, and array offset
//
ByteBuffer(int mark, int pos, int lim, int cap, // package-private
byte[] hb, int offset)
{
super(mark, pos, lim, cap, 0);
this.hb = hb;
this.offset = offset;
}
// Creates a new buffer with the given mark, position, limit, and capacity
//
ByteBuffer(int mark, int pos, int lim, int cap) { // package-private
this(mark, pos, lim, cap, null, 0);
}
/**
* Allocates a new direct byte buffer.
*
* The new buffer's position will be zero, its limit will be its
* capacity, its mark will be undefined, and each of its elements will be
* initialized to zero. Whether or not it has a
* {@link #hasArray backing array} is unspecified.
*
* @param capacity
* The new buffer's capacity, in bytes
*
* @return The new byte buffer
*
* @throws IllegalArgumentException
* If the capacity is a negative integer
*/
public static ByteBuffer allocateDirect(int capacity) {
if (capacity < 0) {
throw new IllegalArgumentException("capacity < 0: " + capacity);
}
DirectByteBuffer.MemoryRef memoryRef = new DirectByteBuffer.MemoryRef(capacity);
return new DirectByteBuffer(capacity, memoryRef);
}
/**
* Allocates a new byte buffer.
*
*
The new buffer's position will be zero, its limit will be its
* capacity, its mark will be undefined, and each of its elements will be
* initialized to zero. It will have a {@link #array backing array},
* and its {@link #arrayOffset array offset} will be zero.
*
* @param capacity
* The new buffer's capacity, in bytes
*
* @return The new byte buffer
*
* @throws IllegalArgumentException
* If the capacity is a negative integer
*/
public static ByteBuffer allocate(int capacity) {
if (capacity < 0)
throw new IllegalArgumentException();
return new HeapByteBuffer(capacity, capacity);
}
/**
* Wraps a byte array into a buffer.
*
*
The new buffer will be backed by the given byte array;
* that is, modifications to the buffer will cause the array to be modified
* and vice versa. The new buffer's capacity will be
* array.length, its position will be offset, its limit
* will be offset + length, and its mark will be undefined. Its
* {@link #array backing array} will be the given array, and
* its {@link #arrayOffset array offset} will be zero.
*
* @param array
* The array that will back the new buffer
*
* @param offset
* The offset of the subarray to be used; must be non-negative and
* no larger than array.length. The new buffer's position
* will be set to this value.
*
* @param length
* The length of the subarray to be used;
* must be non-negative and no larger than
* array.length - offset.
* The new buffer's limit will be set to offset + length.
*
* @return The new byte buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the offset and length
* parameters do not hold
*/
public static ByteBuffer wrap(byte[] array,
int offset, int length)
{
try {
return new HeapByteBuffer(array, offset, length);
} catch (IllegalArgumentException x) {
throw new IndexOutOfBoundsException();
}
}
/**
* Wraps a byte array into a buffer.
*
* The new buffer will be backed by the given byte array;
* that is, modifications to the buffer will cause the array to be modified
* and vice versa. The new buffer's capacity and limit will be
* array.length, its position will be zero, and its mark will be
* undefined. Its {@link #array backing array} will be the
* given array, and its {@link #arrayOffset array offset>} will
* be zero.
*
* @param array
* The array that will back this buffer
*
* @return The new byte buffer
*/
public static ByteBuffer wrap(byte[] array) {
return wrap(array, 0, array.length);
}
/**
* Creates a new byte buffer whose content is a shared subsequence of
* this buffer's content.
*
* The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's position will be zero, its capacity and its limit
* will be the number of bytes remaining in this buffer, and its mark
* will be undefined. The new buffer will be direct if, and only if, this
* buffer is direct, and it will be read-only if, and only if, this buffer
* is read-only.
*
* @return The new byte buffer
*/
public abstract ByteBuffer slice();
/**
* Creates a new byte buffer that shares this buffer's content.
*
* The content of the new buffer will be that of this buffer. Changes
* to this buffer's content will be visible in the new buffer, and vice
* versa; the two buffers' position, limit, and mark values will be
* independent.
*
*
The new buffer's capacity, limit, position, and mark values will be
* identical to those of this buffer. The new buffer will be direct if,
* and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only.
*
* @return The new byte buffer
*/
public abstract ByteBuffer duplicate();
/**
* Creates a new, read-only byte buffer that shares this buffer's
* content.
*
* The content of the new buffer will be that of this buffer. Changes
* to this buffer's content will be visible in the new buffer; the new
* buffer itself, however, will be read-only and will not allow the shared
* content to be modified. The two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's capacity, limit, position, and mark values will be
* identical to those of this buffer.
*
*
If this buffer is itself read-only then this method behaves in
* exactly the same way as the {@link #duplicate duplicate} method.
*
* @return The new, read-only byte buffer
*/
public abstract ByteBuffer asReadOnlyBuffer();
// -- Singleton get/put methods --
/**
* Relative get method. Reads the byte at this buffer's
* current position, and then increments the position.
*
* @return The byte at the buffer's current position
*
* @throws BufferUnderflowException
* If the buffer's current position is not smaller than its limit
*/
public abstract byte get();
/**
* Relative put method (optional operation).
*
* Writes the given byte into this buffer at the current
* position, and then increments the position.
*
* @param b
* The byte to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If this buffer's current position is not smaller than its limit
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer put(byte b);
/**
* Absolute get method. Reads the byte at the given
* index.
*
* @param index
* The index from which the byte will be read
*
* @return The byte at the given index
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit
*/
public abstract byte get(int index);
/**
* Absolute put method (optional operation).
*
* Writes the given byte into this buffer at the given
* index.
*
* @param index
* The index at which the byte will be written
*
* @param b
* The byte value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer put(int index, byte b);
// -- Bulk get operations --
/**
* Relative bulk get method.
*
* This method transfers bytes from this buffer into the given
* destination array. If there are fewer bytes remaining in the
* buffer than are required to satisfy the request, that is, if
* length > remaining(), then no
* bytes are transferred and a {@link BufferUnderflowException} is
* thrown.
*
*
Otherwise, this method copies length bytes from this
* buffer into the given array, starting at the current position of this
* buffer and at the given offset in the array. The position of this
* buffer is then incremented by length.
*
*
In other words, an invocation of this method of the form
* src.get(dst, off, len) has exactly the same effect as
* the loop
*
*
{@code
* for (int i = off; i < off + len; i++)
* dst[i] = src.get();
* }
*
* except that it first checks that there are sufficient bytes in
* this buffer and it is potentially much more efficient.
*
* @param dst
* The array into which bytes are to be written
*
* @param offset
* The offset within the array of the first byte 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
*
* @return This buffer
*
* @throws BufferUnderflowException
* If there are fewer than length bytes
* remaining in this buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the offset and length
* parameters do not hold
*/
public ByteBuffer get(byte[] dst, int offset, int length) {
checkBounds(offset, length, dst.length);
if (length > remaining())
throw new BufferUnderflowException();
int end = offset + length;
for (int i = offset; i < end; i++)
dst[i] = get();
return this;
}
/**
* Relative bulk get method.
*
* This method transfers bytes from this buffer into the given
* destination array. An invocation of this method of the form
* src.get(a) behaves in exactly the same way as the invocation
*
*
* src.get(a, 0, a.length)
*
* @param dst
* The destination array
*
* @return This buffer
*
* @throws BufferUnderflowException
* If there are fewer than length bytes
* remaining in this buffer
*/
public ByteBuffer get(byte[] dst) {
return get(dst, 0, dst.length);
}
// -- Bulk put operations --
/**
* Relative bulk put method (optional operation).
*
* This method transfers the bytes remaining in the given source
* buffer into this buffer. If there are more bytes remaining in the
* source buffer than in this buffer, that is, if
* src.remaining() > remaining(),
* then no bytes are transferred and a {@link
* BufferOverflowException} is thrown.
*
*
Otherwise, this method copies
* n = src.remaining() bytes from the given
* buffer into this buffer, starting at each buffer's current position.
* The positions of both buffers are then incremented by n.
*
*
In other words, an invocation of this method of the form
* dst.put(src) has exactly the same effect as the loop
*
*
* while (src.hasRemaining())
* dst.put(src.get());
*
* except that it first checks that there is sufficient space in this
* buffer and it is potentially much more efficient.
*
* @param src
* The source buffer from which bytes are to be read;
* must not be this buffer
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
* for the remaining bytes in the source buffer
*
* @throws IllegalArgumentException
* If the source buffer is this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public ByteBuffer put(ByteBuffer src) {
if (!isAccessible()) {
throw new IllegalStateException("buffer is inaccessible");
}
if (src == this) {
throw new IllegalArgumentException();
}
if (isReadOnly) {
throw new ReadOnlyBufferException();
}
int n = src.remaining();
if (n > remaining()) {
throw new BufferOverflowException();
}
// Note that we use offset instead of arrayOffset because arrayOffset is specified to
// throw for read only buffers. Our use of arrayOffset here is provably safe, we only
// use it to read *from* readOnly buffers.
if (this.hb != null && src.hb != null) {
// System.arraycopy is intrinsified by art and therefore tiny bit faster than memmove
System.arraycopy(src.hb, src.position() + src.offset, hb, position() + offset, n);
} else {
// Use the buffer object (and the raw memory address) if it's a direct buffer. Note that
// isDirect() doesn't imply !hasArray(), ByteBuffer.allocateDirect allocated buffer will
// have a backing, non-gc-movable byte array. JNI allocated direct byte buffers WILL NOT
// have a backing array.
final Object srcObject = src.isDirect() ? src : src.hb;
int srcOffset = src.position();
if (!src.isDirect()) {
srcOffset += src.offset;
}
final ByteBuffer dst = this;
final Object dstObject = dst.isDirect() ? dst : dst.hb;
int dstOffset = dst.position();
if (!dst.isDirect()) {
dstOffset += dst.offset;
}
Memory.memmove(dstObject, dstOffset, srcObject, srcOffset, n);
}
src.position(src.limit());
this.position(this.position() + n);
return this;
}
/**
* Relative bulk put method (optional operation).
*
* This method transfers bytes into this buffer from the given
* source array. If there are more bytes to be copied from the array
* than remain in this buffer, that is, if
* length > remaining(), then no
* bytes are transferred and a {@link BufferOverflowException} is
* thrown.
*
*
Otherwise, this method copies length bytes from the
* given array into this buffer, starting at the given offset in the array
* and at the current position of this buffer. The position of this buffer
* is then incremented by length.
*
*
In other words, an invocation of this method of the form
* dst.put(src, off, len) has exactly the same effect as
* the loop
*
*
{@code
* for (int i = off; i < off + len; i++)
* dst.put(a[i]);
* }
*
* except that it first checks that there is sufficient space in this
* buffer and it is potentially much more efficient.
*
* @param src
* The array from which bytes are to be read
*
* @param offset
* The offset within the array of the first byte to be read;
* must be non-negative and no larger than array.length
*
* @param length
* The number of bytes to be read from the given array;
* must be non-negative and no larger than
* array.length - offset
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the offset and length
* parameters do not hold
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public ByteBuffer put(byte[] src, int offset, int length) {
checkBounds(offset, length, src.length);
if (length > remaining())
throw new BufferOverflowException();
int end = offset + length;
for (int i = offset; i < end; i++)
this.put(src[i]);
return this;
}
/**
* Relative bulk put method (optional operation).
*
* This method transfers the entire content of the given source
* byte array into this buffer. An invocation of this method of the
* form dst.put(a) behaves in exactly the same way as the
* invocation
*
*
* dst.put(a, 0, a.length)
*
* @param src
* The source array
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public final ByteBuffer put(byte[] src) {
return put(src, 0, src.length);
}
// -- Other stuff --
/**
* Tells whether or not this buffer is backed by an accessible byte
* array.
*
* If this method returns true then the {@link #array() array}
* and {@link #arrayOffset() arrayOffset} methods may safely be invoked.
*
*
* @return true if, and only if, this buffer
* is backed by an array and is not read-only
*/
public final boolean hasArray() {
return (hb != null) && !isReadOnly;
}
/**
* Returns the byte array that backs this
* buffer (optional operation).
*
* Modifications to this buffer's content will cause the returned
* array's content to be modified, and vice versa.
*
*
Invoke the {@link #hasArray hasArray} method before invoking this
* method in order to ensure that this buffer has an accessible backing
* array.
*
* @return The array that backs this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is backed by an array but is read-only
*
* @throws UnsupportedOperationException
* If this buffer is not backed by an accessible array
*/
public final byte[] array() {
if (hb == null)
throw new UnsupportedOperationException();
if (isReadOnly)
throw new ReadOnlyBufferException();
return hb;
}
/**
* Returns the offset within this buffer's backing array of the first
* element of the buffer (optional operation).
*
* If this buffer is backed by an array then buffer position p
* corresponds to array index p + arrayOffset().
*
*
Invoke the {@link #hasArray hasArray} method before invoking this
* method in order to ensure that this buffer has an accessible backing
* array.
*
* @return The offset within this buffer's array
* of the first element of the buffer
*
* @throws ReadOnlyBufferException
* If this buffer is backed by an array but is read-only
*
* @throws UnsupportedOperationException
* If this buffer is not backed by an accessible array
*/
public final int arrayOffset() {
if (hb == null)
throw new UnsupportedOperationException();
if (isReadOnly)
throw new ReadOnlyBufferException();
return offset;
}
/**
* Compacts this buffer (optional operation).
*
* The bytes between the buffer's current position and its limit,
* if any, are copied to the beginning of the buffer. That is, the
* byte at index p = position() is copied
* to index zero, the byte at index p + 1 is copied
* to index one, and so forth until the byte at index
* limit() - 1 is copied to index
* n = limit() - 1 - p.
* The buffer's position is then set to n+1 and its limit is set to
* its capacity. The mark, if defined, is discarded.
*
*
The buffer's position is set to the number of bytes copied,
* rather than to zero, so that an invocation of this method can be
* followed immediately by an invocation of another relative put
* method.
*
*
* Invoke this method after writing data from a buffer in case the
* write was incomplete. The following loop, for example, copies bytes
* from one channel to another via the buffer buf:
*
*
{@code
* buf.clear(); // Prepare buffer for use
* while (in.read(buf) >= 0 || buf.position != 0) {
* buf.flip();
* out.write(buf);
* buf.compact(); // In case of partial write
* }
* }
*
*
* @return This buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer compact();
/**
* Tells whether or not this byte buffer is direct.
*
* @return true if, and only if, this buffer is direct
*/
public abstract boolean isDirect();
/**
* Returns a string summarizing the state of this buffer.
*
* @return A summary string
*/
public String toString() {
StringBuffer sb = new StringBuffer();
sb.append(getClass().getName());
sb.append("[pos=");
sb.append(position());
sb.append(" lim=");
sb.append(limit());
sb.append(" cap=");
sb.append(capacity());
sb.append("]");
return sb.toString();
}
/**
* Returns the current hash code of this buffer.
*
* The hash code of a byte buffer depends only upon its remaining
* elements; that is, upon the elements from position() up to, and
* including, the element at limit() - 1.
*
*
Because buffer hash codes are content-dependent, it is inadvisable
* to use buffers as keys in hash maps or similar data structures unless it
* is known that their contents will not change.
*
* @return The current hash code of this buffer
*/
public int hashCode() {
int h = 1;
int p = position();
for (int i = limit() - 1; i >= p; i--)
h = 31 * h + (int)get(i);
return h;
}
/**
* Tells whether or not this buffer is equal to another object.
*
* Two byte buffers are equal if, and only if,
*
*
*
* They have the same element type,
*
* They have the same number of remaining elements, and
*
*
* The two sequences of remaining elements, considered
* independently of their starting positions, are pointwise equal.
*
*
*
*
* A byte buffer is not equal to any other type of object.
*
* @param ob The object to which this buffer is to be compared
*
* @return true if, and only if, this buffer is equal to the
* given object
*/
public boolean equals(Object ob) {
if (this == ob)
return true;
if (!(ob instanceof ByteBuffer))
return false;
ByteBuffer that = (ByteBuffer)ob;
if (this.remaining() != that.remaining())
return false;
int p = this.position();
for (int i = this.limit() - 1, j = that.limit() - 1; i >= p; i--, j--)
if (!equals(this.get(i), that.get(j)))
return false;
return true;
}
private static boolean equals(byte x, byte y) {
return x == y;
}
/**
* Compares this buffer to another.
*
* Two byte buffers are compared by comparing their sequences of
* remaining elements lexicographically, without regard to the starting
* position of each sequence within its corresponding buffer.
*
*
*
*
*
*
*
*
* Pairs of {@code byte} elements are compared as if by invoking
* {@link Byte#compare(byte,byte)}.
*
*
A byte buffer is not comparable to any other type of object.
*
* @return A negative integer, zero, or a positive integer as this buffer
* is less than, equal to, or greater than the given buffer
*/
public int compareTo(ByteBuffer that) {
int n = this.position() + Math.min(this.remaining(), that.remaining());
for (int i = this.position(), j = that.position(); i < n; i++, j++) {
int cmp = compare(this.get(i), that.get(j));
if (cmp != 0)
return cmp;
}
return this.remaining() - that.remaining();
}
private static int compare(byte x, byte y) {
return Byte.compare(x, y);
}
// -- Other char stuff --
// -- Other byte stuff: Access to binary data --
boolean bigEndian // package-private
= true;
boolean nativeByteOrder // package-private
= (Bits.byteOrder() == ByteOrder.BIG_ENDIAN);
/**
* Retrieves this buffer's byte order.
*
*
The byte order is used when reading or writing multibyte values, and
* when creating buffers that are views of this byte buffer. The order of
* a newly-created byte buffer is always {@link ByteOrder#BIG_ENDIAN
* BIG_ENDIAN}.
*
* @return This buffer's byte order
*/
public final ByteOrder order() {
return bigEndian ? ByteOrder.BIG_ENDIAN : ByteOrder.LITTLE_ENDIAN;
}
/**
* Modifies this buffer's byte order.
*
* @param bo
* The new byte order,
* either {@link ByteOrder#BIG_ENDIAN BIG_ENDIAN}
* or {@link ByteOrder#LITTLE_ENDIAN LITTLE_ENDIAN}
*
* @return This buffer
*/
public final ByteBuffer order(ByteOrder bo) {
bigEndian = (bo == ByteOrder.BIG_ENDIAN);
nativeByteOrder =
(bigEndian == (Bits.byteOrder() == ByteOrder.BIG_ENDIAN));
return this;
}
// Unchecked accessors, for use by ByteBufferAs-X-Buffer classes
//
abstract byte _get(int i); // package-private
abstract void _put(int i, byte b); // package-private
/**
* Relative get method for reading a char value.
*
* Reads the next two bytes at this buffer's current position,
* composing them into a char value according to the current byte order,
* and then increments the position by two.
*
* @return The char value at the buffer's current position
*
* @throws BufferUnderflowException
* If there are fewer than two bytes
* remaining in this buffer
*/
public abstract char getChar();
/**
* Relative put method for writing a char
* value (optional operation).
*
* Writes two bytes containing the given char value, in the
* current byte order, into this buffer at the current position, and then
* increments the position by two.
*
* @param value
* The char value to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If there are fewer than two bytes
* remaining in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putChar(char value);
/**
* Absolute get method for reading a char value.
*
* Reads two bytes at the given index, composing them into a
* char value according to the current byte order.
*
* @param index
* The index from which the bytes will be read
*
* @return The char value at the given index
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus one
*/
public abstract char getChar(int index);
char getCharUnchecked(int index) {
throw new UnsupportedOperationException();
}
void getUnchecked(int pos, char[] dst, int dstOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Absolute put method for writing a char
* value (optional operation).
*
* Writes two bytes containing the given char value, in the
* current byte order, into this buffer at the given index.
*
* @param index
* The index at which the bytes will be written
*
* @param value
* The char value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus one
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putChar(int index, char value);
void putCharUnchecked(int index, char value) {
throw new UnsupportedOperationException();
}
void putUnchecked(int pos, char[] dst, int srcOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Creates a view of this byte buffer as a char buffer.
*
* The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's position will be zero, its capacity and its limit
* will be the number of bytes remaining in this buffer divided by
* two, and its mark will be undefined. The new buffer will be direct
* if, and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only.
*
* @return A new char buffer
*/
public abstract CharBuffer asCharBuffer();
/**
* Relative get method for reading a short value.
*
* Reads the next two bytes at this buffer's current position,
* composing them into a short value according to the current byte order,
* and then increments the position by two.
*
* @return The short value at the buffer's current position
*
* @throws BufferUnderflowException
* If there are fewer than two bytes
* remaining in this buffer
*/
public abstract short getShort();
/**
* Relative put method for writing a short
* value (optional operation).
*
* Writes two bytes containing the given short value, in the
* current byte order, into this buffer at the current position, and then
* increments the position by two.
*
* @param value
* The short value to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If there are fewer than two bytes
* remaining in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putShort(short value);
/**
* Absolute get method for reading a short value.
*
* Reads two bytes at the given index, composing them into a
* short value according to the current byte order.
*
* @param index
* The index from which the bytes will be read
*
* @return The short value at the given index
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus one
*/
public abstract short getShort(int index);
short getShortUnchecked(int index) {
throw new UnsupportedOperationException();
}
void getUnchecked(int pos, short[] dst, int dstOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Absolute put method for writing a short
* value (optional operation).
*
* Writes two bytes containing the given short value, in the
* current byte order, into this buffer at the given index.
*
* @param index
* The index at which the bytes will be written
*
* @param value
* The short value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus one
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putShort(int index, short value);
void putShortUnchecked(int index, short value) {
throw new UnsupportedOperationException();
}
void putUnchecked(int pos, short[] dst, int srcOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Creates a view of this byte buffer as a short buffer.
*
* The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's position will be zero, its capacity and its limit
* will be the number of bytes remaining in this buffer divided by
* two, and its mark will be undefined. The new buffer will be direct
* if, and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only.
*
* @return A new short buffer
*/
public abstract ShortBuffer asShortBuffer();
/**
* Relative get method for reading an int value.
*
* Reads the next four bytes at this buffer's current position,
* composing them into an int value according to the current byte order,
* and then increments the position by four.
*
* @return The int value at the buffer's current position
*
* @throws BufferUnderflowException
* If there are fewer than four bytes
* remaining in this buffer
*/
public abstract int getInt();
/**
* Relative put method for writing an int
* value (optional operation).
*
* Writes four bytes containing the given int value, in the
* current byte order, into this buffer at the current position, and then
* increments the position by four.
*
* @param value
* The int value to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If there are fewer than four bytes
* remaining in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putInt(int value);
/**
* Absolute get method for reading an int value.
*
* Reads four bytes at the given index, composing them into a
* int value according to the current byte order.
*
* @param index
* The index from which the bytes will be read
*
* @return The int value at the given index
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus three
*/
public abstract int getInt(int index);
int getIntUnchecked(int index) {
throw new UnsupportedOperationException();
}
void getUnchecked(int pos, int[] dst, int dstOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Absolute put method for writing an int
* value (optional operation).
*
* Writes four bytes containing the given int value, in the
* current byte order, into this buffer at the given index.
*
* @param index
* The index at which the bytes will be written
*
* @param value
* The int value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus three
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putInt(int index, int value);
void putIntUnchecked(int index, int value) {
throw new UnsupportedOperationException();
}
void putUnchecked(int pos, int[] dst, int srcOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Creates a view of this byte buffer as an int buffer.
*
* The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's position will be zero, its capacity and its limit
* will be the number of bytes remaining in this buffer divided by
* four, and its mark will be undefined. The new buffer will be direct
* if, and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only.
*
* @return A new int buffer
*/
public abstract IntBuffer asIntBuffer();
/**
* Relative get method for reading a long value.
*
* Reads the next eight bytes at this buffer's current position,
* composing them into a long value according to the current byte order,
* and then increments the position by eight.
*
* @return The long value at the buffer's current position
*
* @throws BufferUnderflowException
* If there are fewer than eight bytes
* remaining in this buffer
*/
public abstract long getLong();
/**
* Relative put method for writing a long
* value (optional operation).
*
* Writes eight bytes containing the given long value, in the
* current byte order, into this buffer at the current position, and then
* increments the position by eight.
*
* @param value
* The long value to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If there are fewer than eight bytes
* remaining in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putLong(long value);
/**
* Absolute get method for reading a long value.
*
* Reads eight bytes at the given index, composing them into a
* long value according to the current byte order.
*
* @param index
* The index from which the bytes will be read
*
* @return The long value at the given index
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus seven
*/
public abstract long getLong(int index);
long getLongUnchecked(int index) {
throw new UnsupportedOperationException();
}
void getUnchecked(int pos, long[] dst, int dstOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Absolute put method for writing a long
* value (optional operation).
*
* Writes eight bytes containing the given long value, in the
* current byte order, into this buffer at the given index.
*
* @param index
* The index at which the bytes will be written
*
* @param value
* The long value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus seven
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putLong(int index, long value);
void putLongUnchecked(int index, long value) {
throw new UnsupportedOperationException();
}
void putUnchecked(int pos, long[] dst, int srcOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Creates a view of this byte buffer as a long buffer.
*
* The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's position will be zero, its capacity and its limit
* will be the number of bytes remaining in this buffer divided by
* eight, and its mark will be undefined. The new buffer will be direct
* if, and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only.
*
* @return A new long buffer
*/
public abstract LongBuffer asLongBuffer();
/**
* Relative get method for reading a float value.
*
* Reads the next four bytes at this buffer's current position,
* composing them into a float value according to the current byte order,
* and then increments the position by four.
*
* @return The float value at the buffer's current position
*
* @throws BufferUnderflowException
* If there are fewer than four bytes
* remaining in this buffer
*/
public abstract float getFloat();
/**
* Relative put method for writing a float
* value (optional operation).
*
* Writes four bytes containing the given float value, in the
* current byte order, into this buffer at the current position, and then
* increments the position by four.
*
* @param value
* The float value to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If there are fewer than four bytes
* remaining in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putFloat(float value);
/**
* Absolute get method for reading a float value.
*
* Reads four bytes at the given index, composing them into a
* float value according to the current byte order.
*
* @param index
* The index from which the bytes will be read
*
* @return The float value at the given index
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus three
*/
public abstract float getFloat(int index);
float getFloatUnchecked(int index) {
throw new UnsupportedOperationException();
}
void getUnchecked(int pos, float[] dst, int dstOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Absolute put method for writing a float
* value (optional operation).
*
* Writes four bytes containing the given float value, in the
* current byte order, into this buffer at the given index.
*
* @param index
* The index at which the bytes will be written
*
* @param value
* The float value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus three
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putFloat(int index, float value);
void putFloatUnchecked(int index, float value) {
throw new UnsupportedOperationException();
}
void putUnchecked(int pos, float[] dst, int srcOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Creates a view of this byte buffer as a float buffer.
*
* The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's position will be zero, its capacity and its limit
* will be the number of bytes remaining in this buffer divided by
* four, and its mark will be undefined. The new buffer will be direct
* if, and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only.
*
* @return A new float buffer
*/
public abstract FloatBuffer asFloatBuffer();
/**
* Relative get method for reading a double value.
*
* Reads the next eight bytes at this buffer's current position,
* composing them into a double value according to the current byte order,
* and then increments the position by eight.
*
* @return The double value at the buffer's current position
*
* @throws BufferUnderflowException
* If there are fewer than eight bytes
* remaining in this buffer
*/
public abstract double getDouble();
/**
* Relative put method for writing a double
* value (optional operation).
*
* Writes eight bytes containing the given double value, in the
* current byte order, into this buffer at the current position, and then
* increments the position by eight.
*
* @param value
* The double value to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If there are fewer than eight bytes
* remaining in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putDouble(double value);
/**
* Absolute get method for reading a double value.
*
* Reads eight bytes at the given index, composing them into a
* double value according to the current byte order.
*
* @param index
* The index from which the bytes will be read
*
* @return The double value at the given index
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus seven
*/
public abstract double getDouble(int index);
double getDoubleUnchecked(int index) {
throw new UnsupportedOperationException();
}
void getUnchecked(int pos, double[] dst, int dstOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Absolute put method for writing a double
* value (optional operation).
*
* Writes eight bytes containing the given double value, in the
* current byte order, into this buffer at the given index.
*
* @param index
* The index at which the bytes will be written
*
* @param value
* The double value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If index is negative
* or not smaller than the buffer's limit,
* minus seven
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract ByteBuffer putDouble(int index, double value);
void putDoubleUnchecked(int index, double value) {
throw new UnsupportedOperationException();
}
void putUnchecked(int pos, double[] dst, int srcOffset, int length) {
throw new UnsupportedOperationException();
}
/**
* Creates a view of this byte buffer as a double buffer.
*
* The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
*
The new buffer's position will be zero, its capacity and its limit
* will be the number of bytes remaining in this buffer divided by
* eight, and its mark will be undefined. The new buffer will be direct
* if, and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only.
*
* @return A new double buffer
*/
public abstract DoubleBuffer asDoubleBuffer();
/**
* @hide
*/
public boolean isAccessible() {
return true;
}
/**
* @hide
*/
public void setAccessible(boolean value) {
throw new UnsupportedOperationException();
}
}