JDK8/Java8源码在线阅读
/*
* 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
#warn This file is preprocessed before being compiled
package java.nio;
#if[char]
import java.io.IOException;
#end[char]
#if[streamableType]
import java.util.Spliterator;
import java.util.stream.StreamSupport;
import java.util.stream.$Streamtype$Stream;
#end[streamableType]
/**
* $A$ $type$ buffer.
*
* <p> This class defines {#if[byte]?six:four} categories of operations upon
* $type$ buffers:
*
* <ul>
*
* <li><p> Absolute and relative {@link #get() <i>get</i>} and
* {@link #put($type$) <i>put</i>} methods that read and write
* single $type$s; </p></li>
*
* <li><p> Relative {@link #get($type$[]) <i>bulk get</i>}
* methods that transfer contiguous sequences of $type$s from this buffer
* into an array; {#if[!byte]?and}</p></li>
*
* <li><p> Relative {@link #put($type$[]) <i>bulk put</i>}
* methods that transfer contiguous sequences of $type$s from $a$
* $type$ array{#if[char]?, a string,} or some other $type$
* buffer into this buffer;{#if[!byte]? and} </p></li>
*
#if[byte]
*
* <li><p> Absolute and relative {@link #getChar() <i>get</i>}
* and {@link #putChar(char) <i>put</i>} methods that read and
* write values of other primitive types, translating them to and from
* sequences of bytes in a particular byte order; </p></li>
*
* <li><p> Methods for creating <i><a href="#views">view buffers</a></i>,
* which allow a byte buffer to be viewed as a buffer containing values of
* some other primitive type; and </p></li>
*
#end[byte]
*
* <li><p> Methods for {@link #compact compacting}, {@link
* #duplicate duplicating}, and {@link #slice slicing}
* $a$ $type$ buffer. </p></li>
*
* </ul>
*
* <p> $Type$ buffers can be created either by {@link #allocate
* <i>allocation</i>}, which allocates space for the buffer's
*
#if[byte]
*
* content, or by {@link #wrap($type$[]) <i>wrapping</i>} an
* existing $type$ array {#if[char]?or string} into a buffer.
*
#else[byte]
*
* content, by {@link #wrap($type$[]) <i>wrapping</i>} an existing
* $type$ array {#if[char]?or string} into a buffer, or by creating a
* <a href="ByteBuffer.html#views"><i>view</i></a> of an existing byte buffer.
*
#end[byte]
*
#if[byte]
*
* <a name="direct"></a>
* <h2> Direct <i>vs.</i> non-direct buffers </h2>
*
* <p> A byte buffer is either <i>direct</i> or <i>non-direct</i>. 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.
*
* <p> 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.
*
* <p> 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.
*
* <p> 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.
*
*
* <a name="bin"></a>
* <h2> Access to binary data </h2>
*
* <p> This class defines methods for reading and writing values of all other
* primitive types, except <tt>boolean</tt>. 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}.
*
* <p> For access to heterogeneous binary data, that is, sequences of values of
* different types, this class defines a family of absolute and relative
* <i>get</i> and <i>put</i> methods for each type. For 32-bit floating-point
* values, for example, this class defines:
*
* <blockquote><pre>
* 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)}</pre></blockquote>
*
* <p> Corresponding methods are defined for the types <tt>char</tt>,
* <tt>short</tt>, <tt>int</tt>, <tt>long</tt>, and <tt>double</tt>. The index
* parameters of the absolute <i>get</i> and <i>put</i> methods are in terms of
* bytes rather than of the type being read or written.
*
* <a name="views"></a>
*
* <p> For access to homogeneous binary data, that is, sequences of values of
* the same type, this class defines methods that can create <i>views</i> of a
* given byte buffer. A <i>view buffer</i> 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 <tt>char</tt>, <tt>short</tt>, <tt>int</tt>, <tt>long</tt>, and
* <tt>double</tt>.
*
* <p> View buffers have three important advantages over the families of
* type-specific <i>get</i> and <i>put</i> methods described above:
*
* <ul>
*
* <li><p> A view buffer is indexed not in terms of bytes but rather in terms
* of the type-specific size of its values; </p></li>
*
* <li><p> A view buffer provides relative bulk <i>get</i> and <i>put</i>
* methods that can transfer contiguous sequences of values between a buffer
* and an array or some other buffer of the same type; and </p></li>
*
* <li><p> A view buffer is potentially much more efficient because it will
* be direct if, and only if, its backing byte buffer is direct. </p></li>
*
* </ul>
*
* <p> The byte order of a view buffer is fixed to be that of its byte buffer
* at the time that the view is created. </p>
*
#end[byte]
*
#if[!byte]
*
* <p> Like a byte buffer, $a$ $type$ buffer is either <a
* href="ByteBuffer.html#direct"><i>direct</i> or <i>non-direct</i></a>. A
* $type$ buffer created via the <tt>wrap</tt> methods of this class will
* be non-direct. $A$ $type$ buffer created as a view of a byte buffer will
* be direct if, and only if, the byte buffer itself is direct. Whether or not
* $a$ $type$ buffer is direct may be determined by invoking the {@link
* #isDirect isDirect} method. </p>
*
#end[!byte]
*
#if[char]
*
* <p> This class implements the {@link CharSequence} interface so that
* character buffers may be used wherever character sequences are accepted, for
* example in the regular-expression package <tt>{@link java.util.regex}</tt>.
* </p>
*
#end[char]
*
#if[byte]
* <h2> Invocation chaining </h2>
#end[byte]
*
* <p> 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.
*
#if[byte]
*
* The sequence of statements
*
* <blockquote><pre>
* bb.putInt(0xCAFEBABE);
* bb.putShort(3);
* bb.putShort(45);</pre></blockquote>
*
* can, for example, be replaced by the single statement
*
* <blockquote><pre>
* bb.putInt(0xCAFEBABE).putShort(3).putShort(45);</pre></blockquote>
*
#end[byte]
#if[char]
*
* The sequence of statements
*
* <blockquote><pre>
* cb.put("text/");
* cb.put(subtype);
* cb.put("; charset=");
* cb.put(enc);</pre></blockquote>
*
* can, for example, be replaced by the single statement
*
* <blockquote><pre>
* cb.put("text/").put(subtype).put("; charset=").put(enc);</pre></blockquote>
*
#end[char]
*
*
* @author Mark Reinhold
* @author JSR-51 Expert Group
* @since 1.4
*/
public abstract class $Type$Buffer
extends Buffer
implements Comparable<$Type$Buffer>{#if[char]?, Appendable, CharSequence, Readable}
{
// 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 $type$[] 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
//
$Type$Buffer(int mark, int pos, int lim, int cap, // package-private
$type$[] hb, int offset)
{
super(mark, pos, lim, cap);
this.hb = hb;
this.offset = offset;
}
// Creates a new buffer with the given mark, position, limit, and capacity
//
$Type$Buffer(int mark, int pos, int lim, int cap) { // package-private
this(mark, pos, lim, cap, null, 0);
}
#if[byte]
/**
* Allocates a new direct $type$ buffer.
*
* <p> 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 $type$s
*
* @return The new $type$ buffer
*
* @throws IllegalArgumentException
* If the <tt>capacity</tt> is a negative integer
*/
public static $Type$Buffer allocateDirect(int capacity) {
return new Direct$Type$Buffer(capacity);
}
#end[byte]
/**
* Allocates a new $type$ buffer.
*
* <p> 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 $type$s
*
* @return The new $type$ buffer
*
* @throws IllegalArgumentException
* If the <tt>capacity</tt> is a negative integer
*/
public static $Type$Buffer allocate(int capacity) {
if (capacity < 0)
throw new IllegalArgumentException();
return new Heap$Type$Buffer(capacity, capacity);
}
/**
* Wraps $a$ $type$ array into a buffer.
*
* <p> The new buffer will be backed by the given $type$ array;
* that is, modifications to the buffer will cause the array to be modified
* and vice versa. The new buffer's capacity will be
* <tt>array.length</tt>, its position will be <tt>offset</tt>, its limit
* will be <tt>offset + length</tt>, 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. </p>
*
* @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 <tt>array.length</tt>. 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
* <tt>array.length - offset</tt>.
* The new buffer's limit will be set to <tt>offset + length</tt>.
*
* @return The new $type$ buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>offset</tt> and <tt>length</tt>
* parameters do not hold
*/
public static $Type$Buffer wrap($type$[] array,
int offset, int length)
{
try {
return new Heap$Type$Buffer(array, offset, length);
} catch (IllegalArgumentException x) {
throw new IndexOutOfBoundsException();
}
}
/**
* Wraps $a$ $type$ array into a buffer.
*
* <p> The new buffer will be backed by the given $type$ 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
* <tt>array.length</tt>, 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. </p>
*
* @param array
* The array that will back this buffer
*
* @return The new $type$ buffer
*/
public static $Type$Buffer wrap($type$[] array) {
return wrap(array, 0, array.length);
}
#if[char]
/**
* Attempts to read characters into the specified character buffer.
* The buffer is used as a repository of characters as-is: the only
* changes made are the results of a put operation. No flipping or
* rewinding of the buffer is performed.
*
* @param target the buffer to read characters into
* @return The number of characters added to the buffer, or
* -1 if this source of characters is at its end
* @throws IOException if an I/O error occurs
* @throws NullPointerException if target is null
* @throws ReadOnlyBufferException if target is a read only buffer
* @since 1.5
*/
public int read(CharBuffer target) throws IOException {
// Determine the number of bytes n that can be transferred
int targetRemaining = target.remaining();
int remaining = remaining();
if (remaining == 0)
return -1;
int n = Math.min(remaining, targetRemaining);
int limit = limit();
// Set source limit to prevent target overflow
if (targetRemaining < remaining)
limit(position() + n);
try {
if (n > 0)
target.put(this);
} finally {
limit(limit); // restore real limit
}
return n;
}
/**
* Wraps a character sequence into a buffer.
*
* <p> The content of the new, read-only buffer will be the content of the
* given character sequence. The buffer's capacity will be
* <tt>csq.length()</tt>, its position will be <tt>start</tt>, its limit
* will be <tt>end</tt>, and its mark will be undefined. </p>
*
* @param csq
* The character sequence from which the new character buffer is to
* be created
*
* @param start
* The index of the first character to be used;
* must be non-negative and no larger than <tt>csq.length()</tt>.
* The new buffer's position will be set to this value.
*
* @param end
* The index of the character following the last character to be
* used; must be no smaller than <tt>start</tt> and no larger
* than <tt>csq.length()</tt>.
* The new buffer's limit will be set to this value.
*
* @return The new character buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>start</tt> and <tt>end</tt>
* parameters do not hold
*/
public static CharBuffer wrap(CharSequence csq, int start, int end) {
try {
return new StringCharBuffer(csq, start, end);
} catch (IllegalArgumentException x) {
throw new IndexOutOfBoundsException();
}
}
/**
* Wraps a character sequence into a buffer.
*
* <p> The content of the new, read-only buffer will be the content of the
* given character sequence. The new buffer's capacity and limit will be
* <tt>csq.length()</tt>, its position will be zero, and its mark will be
* undefined. </p>
*
* @param csq
* The character sequence from which the new character buffer is to
* be created
*
* @return The new character buffer
*/
public static CharBuffer wrap(CharSequence csq) {
return wrap(csq, 0, csq.length());
}
#end[char]
/**
* Creates a new $type$ buffer whose content is a shared subsequence of
* this buffer's content.
*
* <p> 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.
*
* <p> The new buffer's position will be zero, its capacity and its limit
* will be the number of $type$s 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. </p>
*
* @return The new $type$ buffer
*/
public abstract $Type$Buffer slice();
/**
* Creates a new $type$ buffer that shares this buffer's content.
*
* <p> 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.
*
* <p> 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. </p>
*
* @return The new $type$ buffer
*/
public abstract $Type$Buffer duplicate();
/**
* Creates a new, read-only $type$ buffer that shares this buffer's
* content.
*
* <p> 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.
*
* <p> The new buffer's capacity, limit, position, and mark values will be
* identical to those of this buffer.
*
* <p> If this buffer is itself read-only then this method behaves in
* exactly the same way as the {@link #duplicate duplicate} method. </p>
*
* @return The new, read-only $type$ buffer
*/
public abstract $Type$Buffer asReadOnlyBuffer();
// -- Singleton get/put methods --
/**
* Relative <i>get</i> method. Reads the $type$ at this buffer's
* current position, and then increments the position.
*
* @return The $type$ at the buffer's current position
*
* @throws BufferUnderflowException
* If the buffer's current position is not smaller than its limit
*/
public abstract $type$ get();
/**
* Relative <i>put</i> method <i>(optional operation)</i>.
*
* <p> Writes the given $type$ into this buffer at the current
* position, and then increments the position. </p>
*
* @param $x$
* The $type$ 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 $Type$Buffer put($type$ $x$);
/**
* Absolute <i>get</i> method. Reads the $type$ at the given
* index.
*
* @param index
* The index from which the $type$ will be read
*
* @return The $type$ at the given index
*
* @throws IndexOutOfBoundsException
* If <tt>index</tt> is negative
* or not smaller than the buffer's limit
*/
public abstract $type$ get(int index);
#if[streamableType]
/**
* Absolute <i>get</i> method. Reads the $type$ at the given
* index without any validation of the index.
*
* @param index
* The index from which the $type$ will be read
*
* @return The $type$ at the given index
*/
abstract $type$ getUnchecked(int index); // package-private
#end[streamableType]
/**
* Absolute <i>put</i> method <i>(optional operation)</i>.
*
* <p> Writes the given $type$ into this buffer at the given
* index. </p>
*
* @param index
* The index at which the $type$ will be written
*
* @param $x$
* The $type$ value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If <tt>index</tt> is negative
* or not smaller than the buffer's limit
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract $Type$Buffer put(int index, $type$ $x$);
// -- Bulk get operations --
/**
* Relative bulk <i>get</i> method.
*
* <p> This method transfers $type$s from this buffer into the given
* destination array. If there are fewer $type$s remaining in the
* buffer than are required to satisfy the request, that is, if
* <tt>length</tt> <tt>></tt> <tt>remaining()</tt>, then no
* $type$s are transferred and a {@link BufferUnderflowException} is
* thrown.
*
* <p> Otherwise, this method copies <tt>length</tt> $type$s 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 <tt>length</tt>.
*
* <p> In other words, an invocation of this method of the form
* <tt>src.get(dst, off, len)</tt> has exactly the same effect as
* the loop
*
* <pre>{@code
* for (int i = off; i < off + len; i++)
* dst[i] = src.get():
* }</pre>
*
* except that it first checks that there are sufficient $type$s in
* this buffer and it is potentially much more efficient.
*
* @param dst
* The array into which $type$s are to be written
*
* @param offset
* The offset within the array of the first $type$ to be
* written; must be non-negative and no larger than
* <tt>dst.length</tt>
*
* @param length
* The maximum number of $type$s to be written to the given
* array; must be non-negative and no larger than
* <tt>dst.length - offset</tt>
*
* @return This buffer
*
* @throws BufferUnderflowException
* If there are fewer than <tt>length</tt> $type$s
* remaining in this buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>offset</tt> and <tt>length</tt>
* parameters do not hold
*/
public $Type$Buffer get($type$[] 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 <i>get</i> method.
*
* <p> This method transfers $type$s from this buffer into the given
* destination array. An invocation of this method of the form
* <tt>src.get(a)</tt> behaves in exactly the same way as the invocation
*
* <pre>
* src.get(a, 0, a.length) </pre>
*
* @param dst
* The destination array
*
* @return This buffer
*
* @throws BufferUnderflowException
* If there are fewer than <tt>length</tt> $type$s
* remaining in this buffer
*/
public $Type$Buffer get($type$[] dst) {
return get(dst, 0, dst.length);
}
// -- Bulk put operations --
/**
* Relative bulk <i>put</i> method <i>(optional operation)</i>.
*
* <p> This method transfers the $type$s remaining in the given source
* buffer into this buffer. If there are more $type$s remaining in the
* source buffer than in this buffer, that is, if
* <tt>src.remaining()</tt> <tt>></tt> <tt>remaining()</tt>,
* then no $type$s are transferred and a {@link
* BufferOverflowException} is thrown.
*
* <p> Otherwise, this method copies
* <i>n</i> = <tt>src.remaining()</tt> $type$s from the given
* buffer into this buffer, starting at each buffer's current position.
* The positions of both buffers are then incremented by <i>n</i>.
*
* <p> In other words, an invocation of this method of the form
* <tt>dst.put(src)</tt> has exactly the same effect as the loop
*
* <pre>
* while (src.hasRemaining())
* dst.put(src.get()); </pre>
*
* 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 $type$s 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 $type$s in the source buffer
*
* @throws IllegalArgumentException
* If the source buffer is this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public $Type$Buffer put($Type$Buffer src) {
if (src == this)
throw new IllegalArgumentException();
if (isReadOnly())
throw new ReadOnlyBufferException();
int n = src.remaining();
if (n > remaining())
throw new BufferOverflowException();
for (int i = 0; i < n; i++)
put(src.get());
return this;
}
/**
* Relative bulk <i>put</i> method <i>(optional operation)</i>.
*
* <p> This method transfers $type$s into this buffer from the given
* source array. If there are more $type$s to be copied from the array
* than remain in this buffer, that is, if
* <tt>length</tt> <tt>></tt> <tt>remaining()</tt>, then no
* $type$s are transferred and a {@link BufferOverflowException} is
* thrown.
*
* <p> Otherwise, this method copies <tt>length</tt> $type$s 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 <tt>length</tt>.
*
* <p> In other words, an invocation of this method of the form
* <tt>dst.put(src, off, len)</tt> has exactly the same effect as
* the loop
*
* <pre>{@code
* for (int i = off; i < off + len; i++)
* dst.put(a[i]);
* }</pre>
*
* 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 $type$s are to be read
*
* @param offset
* The offset within the array of the first $type$ to be read;
* must be non-negative and no larger than <tt>array.length</tt>
*
* @param length
* The number of $type$s to be read from the given array;
* must be non-negative and no larger than
* <tt>array.length - offset</tt>
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>offset</tt> and <tt>length</tt>
* parameters do not hold
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public $Type$Buffer put($type$[] 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 <i>put</i> method <i>(optional operation)</i>.
*
* <p> This method transfers the entire content of the given source
* $type$ array into this buffer. An invocation of this method of the
* form <tt>dst.put(a)</tt> behaves in exactly the same way as the
* invocation
*
* <pre>
* dst.put(a, 0, a.length) </pre>
*
* @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 $Type$Buffer put($type$[] src) {
return put(src, 0, src.length);
}
#if[char]
/**
* Relative bulk <i>put</i> method <i>(optional operation)</i>.
*
* <p> This method transfers $type$s from the given string into this
* buffer. If there are more $type$s to be copied from the string than
* remain in this buffer, that is, if
* <tt>end - start</tt> <tt>></tt> <tt>remaining()</tt>,
* then no $type$s are transferred and a {@link
* BufferOverflowException} is thrown.
*
* <p> Otherwise, this method copies
* <i>n</i> = <tt>end</tt> - <tt>start</tt> $type$s
* from the given string into this buffer, starting at the given
* <tt>start</tt> index and at the current position of this buffer. The
* position of this buffer is then incremented by <i>n</i>.
*
* <p> In other words, an invocation of this method of the form
* <tt>dst.put(src, start, end)</tt> has exactly the same effect
* as the loop
*
* <pre>{@code
* for (int i = start; i < end; i++)
* dst.put(src.charAt(i));
* }</pre>
*
* except that it first checks that there is sufficient space in this
* buffer and it is potentially much more efficient.
*
* @param src
* The string from which $type$s are to be read
*
* @param start
* The offset within the string of the first $type$ to be read;
* must be non-negative and no larger than
* <tt>string.length()</tt>
*
* @param end
* The offset within the string of the last $type$ to be read,
* plus one; must be non-negative and no larger than
* <tt>string.length()</tt>
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>start</tt> and <tt>end</tt>
* parameters do not hold
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public $Type$Buffer put(String src, int start, int end) {
checkBounds(start, end - start, src.length());
if (isReadOnly())
throw new ReadOnlyBufferException();
if (end - start > remaining())
throw new BufferOverflowException();
for (int i = start; i < end; i++)
this.put(src.charAt(i));
return this;
}
/**
* Relative bulk <i>put</i> method <i>(optional operation)</i>.
*
* <p> This method transfers the entire content of the given source string
* into this buffer. An invocation of this method of the form
* <tt>dst.put(s)</tt> behaves in exactly the same way as the invocation
*
* <pre>
* dst.put(s, 0, s.length()) </pre>
*
* @param src
* The source string
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public final $Type$Buffer put(String src) {
return put(src, 0, src.length());
}
#end[char]
// -- Other stuff --
/**
* Tells whether or not this buffer is backed by an accessible $type$
* array.
*
* <p> If this method returns <tt>true</tt> then the {@link #array() array}
* and {@link #arrayOffset() arrayOffset} methods may safely be invoked.
* </p>
*
* @return <tt>true</tt> 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 $type$ array that backs this
* buffer <i>(optional operation)</i>.
*
* <p> Modifications to this buffer's content will cause the returned
* array's content to be modified, and vice versa.
*
* <p> Invoke the {@link #hasArray hasArray} method before invoking this
* method in order to ensure that this buffer has an accessible backing
* array. </p>
*
* @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 $type$[] 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 <i>(optional operation)</i>.
*
* <p> If this buffer is backed by an array then buffer position <i>p</i>
* corresponds to array index <i>p</i> + <tt>arrayOffset()</tt>.
*
* <p> Invoke the {@link #hasArray hasArray} method before invoking this
* method in order to ensure that this buffer has an accessible backing
* array. </p>
*
* @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 <i>(optional operation)</i>.
*
* <p> The $type$s between the buffer's current position and its limit,
* if any, are copied to the beginning of the buffer. That is, the
* $type$ at index <i>p</i> = <tt>position()</tt> is copied
* to index zero, the $type$ at index <i>p</i> + 1 is copied
* to index one, and so forth until the $type$ at index
* <tt>limit()</tt> - 1 is copied to index
* <i>n</i> = <tt>limit()</tt> - <tt>1</tt> - <i>p</i>.
* The buffer's position is then set to <i>n+1</i> and its limit is set to
* its capacity. The mark, if defined, is discarded.
*
* <p> The buffer's position is set to the number of $type$s copied,
* rather than to zero, so that an invocation of this method can be
* followed immediately by an invocation of another relative <i>put</i>
* method. </p>
*
#if[byte]
*
* <p> 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 <tt>buf</tt>:
*
* <blockquote><pre>{@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
* }
* }</pre></blockquote>
*
#end[byte]
*
* @return This buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract $Type$Buffer compact();
/**
* Tells whether or not this $type$ buffer is direct.
*
* @return <tt>true</tt> if, and only if, this buffer is direct
*/
public abstract boolean isDirect();
#if[!char]
/**
* 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();
}
#end[!char]
// ## Should really use unchecked accessors here for speed
/**
* Returns the current hash code of this buffer.
*
* <p> The hash code of a $type$ buffer depends only upon its remaining
* elements; that is, upon the elements from <tt>position()</tt> up to, and
* including, the element at <tt>limit()</tt> - <tt>1</tt>.
*
* <p> 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. </p>
*
* @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--)
#if[int]
h = 31 * h + get(i);
#else[int]
h = 31 * h + (int)get(i);
#end[int]
return h;
}
/**
* Tells whether or not this buffer is equal to another object.
*
* <p> Two $type$ buffers are equal if, and only if,
*
* <ol>
*
* <li><p> They have the same element type, </p></li>
*
* <li><p> They have the same number of remaining elements, and
* </p></li>
*
* <li><p> The two sequences of remaining elements, considered
* independently of their starting positions, are pointwise equal.
#if[floatingPointType]
* This method considers two $type$ elements {@code a} and {@code b}
* to be equal if
* {@code (a == b) || ($Fulltype$.isNaN(a) && $Fulltype$.isNaN(b))}.
* The values {@code -0.0} and {@code +0.0} are considered to be
* equal, unlike {@link $Fulltype$#equals(Object)}.
#end[floatingPointType]
* </p></li>
*
* </ol>
*
* <p> A $type$ buffer is not equal to any other type of object. </p>
*
* @param ob The object to which this buffer is to be compared
*
* @return <tt>true</tt> 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 $Type$Buffer))
return false;
$Type$Buffer that = ($Type$Buffer)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($type$ x, $type$ y) {
#if[floatingPointType]
return (x == y) || ($Fulltype$.isNaN(x) && $Fulltype$.isNaN(y));
#else[floatingPointType]
return x == y;
#end[floatingPointType]
}
/**
* Compares this buffer to another.
*
* <p> Two $type$ buffers are compared by comparing their sequences of
* remaining elements lexicographically, without regard to the starting
* position of each sequence within its corresponding buffer.
#if[floatingPointType]
* Pairs of {@code $type$} elements are compared as if by invoking
* {@link $Fulltype$#compare($type$,$type$)}, except that
* {@code -0.0} and {@code 0.0} are considered to be equal.
* {@code $Fulltype$.NaN} is considered by this method to be equal
* to itself and greater than all other {@code $type$} values
* (including {@code $Fulltype$.POSITIVE_INFINITY}).
#else[floatingPointType]
* Pairs of {@code $type$} elements are compared as if by invoking
* {@link $Fulltype$#compare($type$,$type$)}.
#end[floatingPointType]
*
* <p> A $type$ 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($Type$Buffer 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($type$ x, $type$ y) {
#if[floatingPointType]
return ((x < y) ? -1 :
(x > y) ? +1 :
(x == y) ? 0 :
$Fulltype$.isNaN(x) ? ($Fulltype$.isNaN(y) ? 0 : +1) : -1);
#else[floatingPointType]
return $Fulltype$.compare(x, y);
#end[floatingPointType]
}
// -- Other char stuff --
#if[char]
/**
* Returns a string containing the characters in this buffer.
*
* <p> The first character of the resulting string will be the character at
* this buffer's position, while the last character will be the character
* at index <tt>limit()</tt> - 1. Invoking this method does not
* change the buffer's position. </p>
*
* @return The specified string
*/
public String toString() {
return toString(position(), limit());
}
abstract String toString(int start, int end); // package-private
// --- Methods to support CharSequence ---
/**
* Returns the length of this character buffer.
*
* <p> When viewed as a character sequence, the length of a character
* buffer is simply the number of characters between the position
* (inclusive) and the limit (exclusive); that is, it is equivalent to
* <tt>remaining()</tt>. </p>
*
* @return The length of this character buffer
*/
public final int length() {
return remaining();
}
/**
* Reads the character at the given index relative to the current
* position.
*
* @param index
* The index of the character to be read, relative to the position;
* must be non-negative and smaller than <tt>remaining()</tt>
*
* @return The character at index
* <tt>position() + index</tt>
*
* @throws IndexOutOfBoundsException
* If the preconditions on <tt>index</tt> do not hold
*/
public final char charAt(int index) {
return get(position() + checkIndex(index, 1));
}
/**
* Creates a new character buffer that represents the specified subsequence
* of this buffer, relative to the current position.
*
* <p> The new buffer will share this buffer's content; that is, if the
* content of this buffer is mutable then modifications to one buffer will
* cause the other to be modified. The new buffer's capacity will be that
* of this buffer, its position will be
* <tt>position()</tt> + <tt>start</tt>, and its limit will be
* <tt>position()</tt> + <tt>end</tt>. 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. </p>
*
* @param start
* The index, relative to the current position, of the first
* character in the subsequence; must be non-negative and no larger
* than <tt>remaining()</tt>
*
* @param end
* The index, relative to the current position, of the character
* following the last character in the subsequence; must be no
* smaller than <tt>start</tt> and no larger than
* <tt>remaining()</tt>
*
* @return The new character buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on <tt>start</tt> and <tt>end</tt>
* do not hold
*/
public abstract CharBuffer subSequence(int start, int end);
// --- Methods to support Appendable ---
/**
* Appends the specified character sequence to this
* buffer <i>(optional operation)</i>.
*
* <p> An invocation of this method of the form <tt>dst.append(csq)</tt>
* behaves in exactly the same way as the invocation
*
* <pre>
* dst.put(csq.toString()) </pre>
*
* <p> Depending on the specification of <tt>toString</tt> for the
* character sequence <tt>csq</tt>, the entire sequence may not be
* appended. For instance, invoking the {@link $Type$Buffer#toString()
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