java.nio.Buffer
java.nio.LongBuffer
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java.lang.Object
A long buffer.
This class defines four categories of operations upon long buffers:
Absolute and relative get and
put methods that read and write
single longs;
Relative bulk get
methods that transfer contiguous sequences of longs from this buffer
into an array; and
Relative bulk put
methods that transfer contiguous sequences of longs from a
long array or some other long
buffer into this buffer; and
Methods for compacting, duplicating, and slicing a long buffer.
Long buffers can be created either by allocation, which allocates space for the buffer's
content, by wrapping an existing
long array into a buffer, or by creating a
view of an existing byte buffer
Like a byte buffer, a long buffer is either direct or non-direct. A
long buffer created via the wrap methods of this class will
be non-direct. A long 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 long buffer is direct may be determined by invoking the isDirect method.
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.
| Field Summary | |
(package private) long[] |
hb
|
(package private) boolean |
isReadOnly
|
(package private) int |
offset
|
| Fields inherited from class java.nio.Buffer |
address |
| Constructor Summary | |
(package private) |
LongBuffer(int mark,
int pos,
int lim,
int cap)
|
(package private) |
LongBuffer(int mark,
int pos,
int lim,
int cap,
long[] hb,
int offset)
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| Method Summary | |
static LongBuffer |
allocate(int capacity)
Allocates a new long buffer. |
long[] |
array()
Returns the long array that backs this buffer (optional operation). |
int |
arrayOffset()
Returns the offset within this buffer's backing array of the first element of the buffer (optional operation). |
abstract LongBuffer |
asReadOnlyBuffer()
Creates a new, read-only long buffer that shares this buffer's content. |
abstract LongBuffer |
compact()
Compacts this buffer (optional operation). |
int |
compareTo(Object ob)
Compares this buffer to another object. |
abstract LongBuffer |
duplicate()
Creates a new long buffer that shares this buffer's content. |
boolean |
equals(Object ob)
Tells whether or not this buffer is equal to another object. |
abstract long |
get()
Relative get method. |
abstract long |
get(int index)
Absolute get method. |
LongBuffer |
get(long[] dst)
Relative bulk get method. |
LongBuffer |
get(long[] dst,
int offset,
int length)
Relative bulk get method. |
boolean |
hasArray()
Tells whether or not this buffer is backed by an accessible long array. |
int |
hashCode()
Returns the current hash code of this buffer. |
abstract boolean |
isDirect()
Tells whether or not this long buffer is direct. |
abstract ByteOrder |
order()
Retrieves this buffer's byte order. |
abstract LongBuffer |
put(int index,
long l)
Absolute put method (optional operation). |
abstract LongBuffer |
put(long l)
Relative put method (optional operation). |
LongBuffer |
put(long[] src)
Relative bulk put method (optional operation). |
LongBuffer |
put(long[] src,
int offset,
int length)
Relative bulk put method (optional operation). |
LongBuffer |
put(LongBuffer src)
Relative bulk put method (optional operation). |
abstract LongBuffer |
slice()
Creates a new long buffer whose content is a shared subsequence of this buffer's content. |
String |
toString()
Returns a string summarizing the state of this buffer. |
static LongBuffer |
wrap(long[] array)
Wraps a long array into a buffer. |
static LongBuffer |
wrap(long[] array,
int offset,
int length)
Wraps a long array into a buffer. |
| Methods inherited from class java.nio.Buffer |
capacity, checkBounds, checkIndex, checkIndex, clear, flip, hasRemaining, isReadOnly, limit, limit, mark, markValue, nextGetIndex, nextGetIndex, nextPutIndex, nextPutIndex, position, position, remaining, reset, rewind |
| Methods inherited from class java.lang.Object |
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
| Field Detail |
final long[] hb
final int offset
boolean isReadOnly
| Constructor Detail |
LongBuffer(int mark,
int pos,
int lim,
int cap,
long[] hb,
int offset)
LongBuffer(int mark,
int pos,
int lim,
int cap)
| Method Detail |
public static LongBuffer allocate(int capacity)
The new buffer's position will be zero, its limit will be its
capacity, and its mark will be undefined. It will have a backing array, and its array
offset will be zero.
capacity - The new buffer's capacity, in longs
IllegalArgumentException - If the capacity is a negative integer
public static LongBuffer wrap(long[] array,
int offset,
int length)
The new buffer will be backed by the the given long 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
backing array will be the given array, and
its array offset will be zero.
array - The array that will back the new bufferoffset - 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.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.
IndexOutOfBoundsException - If the preconditions on the offset and length
parameters do not holdpublic static LongBuffer wrap(long[] array)
The new buffer will be backed by the the given long 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 backing array will be the
given array, and its array offset will
be zero.
array - The array that will back this buffer
public abstract LongBuffer slice()
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 longs 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.
public abstract LongBuffer duplicate()
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.
public abstract LongBuffer asReadOnlyBuffer()
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 duplicate method.
public abstract long get()
BufferUnderflowException - If the buffer's current position is not smaller than its limitpublic abstract LongBuffer put(long l)
Writes the given long into this buffer at the current position, and then increments the position.
l - The long to be written
BufferOverflowException - If this buffer's current position is not smaller than its limit
ReadOnlyBufferException - If this buffer is read-onlypublic abstract long get(int index)
index - The index from which the long will be read
IndexOutOfBoundsException - If index is negative
or not smaller than the buffer's limit
public abstract LongBuffer put(int index,
long l)
Writes the given long into this buffer at the given index.
index - The index at which the long will be writtenl - The long value to be written
IndexOutOfBoundsException - If index is negative
or not smaller than the buffer's limit
ReadOnlyBufferException - If this buffer is read-only
public LongBuffer get(long[] dst,
int offset,
int length)
This method transfers longs from this buffer into the given
destination array. If there are fewer longs remaining in the
buffer than are required to satisfy the request, that is, if
length > remaining(), then no
longs are transferred and a BufferUnderflowException is
thrown.
Otherwise, this method copies length longs 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
for (int i = off; i < off + len; i++)
dst[i] = src.get();
except that it first checks that there are sufficient longs in
this buffer and it is potentially much more efficient.
dst - The array into which longs are to be writtenoffset - The offset within the array of the first long to be
written; must be non-negative and no larger than
dst.lengthlength - The maximum number of longs to be written to the given
array; must be non-negative and no larger than
dst.length - offset
BufferUnderflowException - If there are fewer than length longs
remaining in this buffer
IndexOutOfBoundsException - If the preconditions on the offset and length
parameters do not holdpublic LongBuffer get(long[] dst)
This method transfers longs 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)
BufferUnderflowException - If there are fewer than length longs
remaining in this bufferpublic LongBuffer put(LongBuffer src)
This method transfers the longs remaining in the given source
buffer into this buffer. If there are more longs remaining in the
source buffer than in this buffer, that is, if
src.remaining() > remaining(),
then no longs are transferred and a BufferOverflowException is thrown.
Otherwise, this method copies n = src.remaining() longs 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.
src - The source buffer from which longs are to be read;
must not be this buffer
BufferOverflowException - If there is insufficient space in this buffer
for the remaining longs in the source buffer
IllegalArgumentException - If the source buffer is this buffer
ReadOnlyBufferException - If this buffer is read-only
public LongBuffer put(long[] src,
int offset,
int length)
This method transfers longs into this buffer from the given
source array. If there are more longs to be copied from the array
than remain in this buffer, that is, if
length > remaining(), then no
longs are transferred and a BufferOverflowException is
thrown.
Otherwise, this method copies length longs 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
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.
src - The array from which longs are to be readoffset - The offset within the array of the first long to be read;
must be non-negative and no larger than array.lengthlength - The number of longs to be read from the given array;
must be non-negative and no larger than
array.length - offset
BufferOverflowException - If there is insufficient space in this buffer
IndexOutOfBoundsException - If the preconditions on the offset and length
parameters do not hold
ReadOnlyBufferException - If this buffer is read-onlypublic final LongBuffer put(long[] src)
This method transfers the entire content of the given source long 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)
BufferOverflowException - If there is insufficient space in this buffer
ReadOnlyBufferException - If this buffer is read-onlypublic final boolean hasArray()
If this method returns true then the array
and arrayOffset methods may safely be invoked.
public final long[] array()
Modifications to this buffer's content will cause the returned array's content to be modified, and vice versa.
Invoke the hasArray method before invoking this
method in order to ensure that this buffer has an accessible backing
array.
ReadOnlyBufferException - If this buffer is backed by an array but is read-only
UnsupportedOperationException - If this buffer is not backed by an accessible arraypublic final int arrayOffset()
If this buffer is backed by an array then buffer position p corresponds to array index p + arrayOffset().
Invoke the hasArray method before invoking this
method in order to ensure that this buffer has an accessible backing
array.
ReadOnlyBufferException - If this buffer is backed by an array but is read-only
UnsupportedOperationException - If this buffer is not backed by an accessible arraypublic abstract LongBuffer compact()
The longs between the buffer's current position and its limit, if any, are copied to the beginning of the buffer. That is, the long at index p = position() is copied to index zero, the long at index p + 1 is copied to index one, and so forth until the long 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 longs copied, rather than to zero, so that an invocation of this method can be followed immediately by an invocation of another relative put method.
ReadOnlyBufferException - If this buffer is read-onlypublic abstract boolean isDirect()
public String toString()
toString in class Objectpublic int hashCode()
The hash code of a long 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.
hashCode in class ObjectObject.equals(java.lang.Object),
Hashtablepublic boolean equals(Object ob)
Two long 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 long buffer is not equal to any other type of object.
equals in class Objectob - The object to which this buffer is to be compared
Object.hashCode(),
Hashtablepublic int compareTo(Object ob)
Two long buffers are compared by comparing their sequences of remaining elements lexicographically, without regard to the starting position of each sequence within its corresponding buffer.
A long buffer is not comparable to any other type of object.
compareTo in interface Comparableob - the Object to be compared.
ClassCastException - If the argument is not a long bufferpublic abstract ByteOrder order()
The byte order of a long buffer created by allocation or by
wrapping an existing long array is the native order of the underlying
hardware. The byte order of a long buffer created as a view of a byte buffer is that of the
byte buffer at the moment that the view is created.
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