Comparable<LongBuffer>
public abstract sealed class LongBuffer extends Buffer implements Comparable<LongBuffer>
This class defines four categories of operations upon long buffers:
Absolute and relative get
and put
methods that read and write single longs;
Absolute and relative bulk get
methods that transfer contiguous sequences of longs from this buffer into an array;
Absolute and relative bulk put
methods that transfer contiguous sequences of longs from a long array or some other long buffer into this buffer;
A method for compacting
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.
Modifier and Type | Method | Description |
---|---|---|
static LongBuffer |
allocate |
Allocates a new long buffer. |
final long[] |
array() |
Returns the long array that backs this buffer (optional operation). |
final 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. |
final LongBuffer |
clear() |
Clears this buffer. |
abstract LongBuffer |
compact() |
Compacts this buffer (optional operation). |
int |
compareTo |
Compares this buffer to another. |
abstract LongBuffer |
duplicate() |
Creates a new long buffer that shares this buffer's content. |
boolean |
equals |
Tells whether or not this buffer is equal to another object. |
final LongBuffer |
flip() |
Flips this buffer. |
abstract long |
get() |
Relative get method. |
abstract long |
get |
Absolute get method. |
LongBuffer |
get |
Absolute bulk get method. |
LongBuffer |
get |
Absolute bulk get method. |
LongBuffer |
get |
Relative bulk get method. |
LongBuffer |
get |
Relative bulk get method. |
final 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. |
final LongBuffer |
limit |
Sets this buffer's limit. |
final LongBuffer |
mark() |
Sets this buffer's mark at its position. |
int |
mismatch |
Finds and returns the relative index of the first mismatch between this buffer and a given buffer. |
abstract ByteOrder |
order() |
Retrieves this buffer's byte order. |
final LongBuffer |
position |
Sets this buffer's position. |
abstract LongBuffer |
put |
Absolute put method (optional operation). |
LongBuffer |
put |
Absolute bulk put method (optional operation). |
LongBuffer |
put |
Absolute bulk put method (optional operation). |
LongBuffer |
put |
Absolute bulk put method (optional operation). |
abstract LongBuffer |
put |
Relative put method (optional operation). |
final LongBuffer |
put |
Relative bulk put method (optional operation). |
LongBuffer |
put |
Relative bulk put method (optional operation). |
LongBuffer |
put |
Relative bulk put method (optional operation). |
final LongBuffer |
reset() |
Resets this buffer's position to the previously-marked position. |
final LongBuffer |
rewind() |
Rewinds this buffer. |
abstract LongBuffer |
slice() |
Creates a new long buffer whose content is a shared subsequence of this buffer's content. |
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 |
Wraps a long array into a buffer. |
static LongBuffer |
wrap |
Wraps a long array into a buffer. |
capacity, hasRemaining, isReadOnly, limit, position, remaining
public static LongBuffer allocate(int capacity)
The new buffer's position will be zero, its limit will be its capacity, its mark will be undefined, each of its elements will be initialized to zero, and its byte order will be the native order
of the underlying hardware. It will have a backing array
, and its array offset
will be zero.
capacity
- The new buffer's capacity, in longsIllegalArgumentException
- If the capacity
is a negative integerpublic static LongBuffer wrap(long[] array, int offset, int length)
The new buffer will be backed by 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
, its mark will be undefined, and its byte order will be the native order
of the underlying hardware. 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 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, its mark will be undefined, and its byte order will be the native order
of the underlying hardware. Its backing array
will be the given array, and its array offset
will be zero.
array
- The array that will back this bufferpublic 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, its mark will be undefined, and its byte order will be identical to that 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 slice(int index, int length)
The content of the new buffer will start at position index
in this buffer, and will contain length
elements. 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 length
, its mark will be undefined, and its byte order will be identical to that 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.
slice
in class Buffer
index
- The position in this buffer at which the content of the new buffer will start; must be non-negative and no larger than limit()
length
- The number of elements the new buffer will contain; must be non-negative and no larger than limit() - index
IndexOutOfBoundsException
- If index
is negative or greater than limit()
, length
is negative, or length > limit() - index
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, mark values, and byte order 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, mark values, and byte order 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 writtenBufferOverflowException
- If this buffer's current position is not smaller than its limitReadOnlyBufferException
- If this buffer is read-onlypublic abstract long get(int index)
index
- The index from which the long will be readIndexOutOfBoundsException
- If index
is negative or not smaller than the buffer's limitpublic 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 writtenIndexOutOfBoundsException
- If index
is negative or not smaller than the buffer's limitReadOnlyBufferException
- If this buffer is read-onlypublic 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();
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.length
length
- 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 bufferIndexOutOfBoundsException
- 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)
dst
- The destination arrayBufferUnderflowException
- If there are fewer than length
longs remaining in this bufferpublic LongBuffer get(int index, long[] dst, int offset, int length)
This method transfers length
longs from this buffer into the given array, starting at the given index in this buffer and at the given offset in the array. The position of this buffer is unchanged.
An invocation of this method of the form src.get(index, dst, offset, length)
has exactly the same effect as the following loop except that it first checks the consistency of the supplied parameters and it is potentially much more efficient:
for (int i = offset, j = index; i < offset + length; i++, j++)
dst[i] = src.get(j);
index
- The index in this buffer from which the first long will be read; must be non-negative and less than limit()
dst
- The destination arrayoffset
- The offset within the array of the first long to be written; must be non-negative and less than dst.length
length
- The number of longs to be written to the given array; must be non-negative and no larger than the smaller of limit() - index
and dst.length - offset
IndexOutOfBoundsException
- If the preconditions on the index
, offset
, and length
parameters do not holdpublic LongBuffer get(int index, long[] dst)
This method transfers longs from this buffer into the given destination array. The position of this buffer is unchanged. An invocation of this method of the form src.get(index, dst)
behaves in exactly the same way as the invocation:
src.get(index, dst, 0, dst.length)
index
- The index in this buffer from which the first long will be read; must be non-negative and less than limit()
dst
- The destination arrayIndexOutOfBoundsException
- If index
is negative, not smaller than limit()
, or limit() - index < dst.length
public 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());
src
- The source buffer from which longs are to be read; must not be this bufferBufferOverflowException
- If there is insufficient space in this buffer for the remaining longs in the source bufferIllegalArgumentException
- If the source buffer is this bufferReadOnlyBufferException
- If this buffer is read-onlypublic LongBuffer put(int index, LongBuffer src, int offset, int length)
This method transfers length
longs into this buffer from the given source buffer, starting at the given offset
in the source buffer and the given index
in this buffer. The positions of both buffers are unchanged.
In other words, an invocation of this method of the form dst.put(index, src, offset, length)
has exactly the same effect as the loop
for (int i = offset, j = index; i < offset + length; i++, j++)
dst.put(j, src.get(i));
index
- The index in this buffer at which the first long will be written; must be non-negative and less than limit()
src
- The buffer from which longs are to be readoffset
- The index within the source buffer of the first long to be read; must be non-negative and less than src.limit()
length
- The number of longs to be read from the given buffer; must be non-negative and no larger than the smaller of limit() - index
and src.limit() - offset
IndexOutOfBoundsException
- If the preconditions on the index
, offset
, and length
parameters do not holdReadOnlyBufferException
- If this buffer is read-onlypublic 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(src[i]);
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 src.length
length
- The number of longs to be read from the given array; must be non-negative and no larger than src.length - offset
BufferOverflowException
- If there is insufficient space in this bufferIndexOutOfBoundsException
- If the preconditions on the offset
and length
parameters do not holdReadOnlyBufferException
- 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)
src
- The source arrayBufferOverflowException
- If there is insufficient space in this bufferReadOnlyBufferException
- If this buffer is read-onlypublic LongBuffer put(int index, long[] src, int offset, int length)
This method transfers length
longs from the given array, starting at the given offset in the array and at the given index in this buffer. The position of this buffer is unchanged.
An invocation of this method of the form dst.put(index, src, offset, length)
has exactly the same effect as the following loop except that it first checks the consistency of the supplied parameters and it is potentially much more efficient:
for (int i = offset, j = index; i < offset + length; i++, j++)
dst.put(j, src[i]);
index
- The index in this buffer at which the first long will be written; must be non-negative and less than limit()
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 less than src.length
length
- The number of longs to be read from the given array; must be non-negative and no larger than the smaller of limit() - index
and src.length - offset
IndexOutOfBoundsException
- If the preconditions on the index
, offset
, and length
parameters do not holdReadOnlyBufferException
- If this buffer is read-onlypublic LongBuffer put(int index, long[] src)
This method copies longs into this buffer from the given source array. The position of this buffer is unchanged. An invocation of this method of the form dst.put(index, src)
behaves in exactly the same way as the invocation:
dst.put(index, src, 0, src.length);
index
- The index in this buffer at which the first long will be written; must be non-negative and less than limit()
src
- The array from which longs are to be readIndexOutOfBoundsException
- If index
is negative, not smaller than limit()
, or limit() - index < src.length
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.
array
in class Buffer
ReadOnlyBufferException
- If this buffer is backed by an array but is read-onlyUnsupportedOperationException
- 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.
arrayOffset
in class Buffer
ReadOnlyBufferException
- If this buffer is backed by an array but is read-onlyUnsupportedOperationException
- If this buffer is not backed by an accessible arraypublic final LongBuffer position(int newPosition)
public final LongBuffer limit(int newLimit)
public final LongBuffer mark()
public final LongBuffer reset()
Invoking this method neither changes nor discards the mark's value.
public final LongBuffer clear()
Invoke this method before using a sequence of channel-read or put operations to fill this buffer. For example:
buf.clear(); // Prepare buffer for reading
in.read(buf); // Read data
This method does not actually erase the data in the buffer, but it is named as if it did because it will most often be used in situations in which that might as well be the case.
public final LongBuffer flip()
After a sequence of channel-read or put operations, invoke this method to prepare for a sequence of channel-write or relative get operations. For example:
buf.put(magic); // Prepend header
in.read(buf); // Read data into rest of buffer
buf.flip(); // Flip buffer
out.write(buf); // Write header + data to channel
This method is often used in conjunction with the compact
method when transferring data from one place to another.
public final LongBuffer rewind()
Invoke this method before a sequence of channel-write or get operations, assuming that the limit has already been set appropriately. For example:
out.write(buf); // Write remaining data
buf.rewind(); // Rewind buffer
buf.get(array); // Copy data into array
public 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()
public 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.
public 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.
public int compareTo(LongBuffer that)
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. Pairs of long
elements are compared as if by invoking Long.compare(long,long)
.
A long buffer is not comparable to any other type of object.
compareTo
in interface Comparable<LongBuffer>
that
- the object to be compared.public int mismatch(LongBuffer that)
position
of each buffer and will be in the range of 0 (inclusive) up to the smaller of the remaining
elements in each buffer (exclusive). If the two buffers share a common prefix then the returned index is the length of the common prefix and it follows that there is a mismatch between the two buffers at that index within the respective buffers. If one buffer is a proper prefix of the other then the returned index is the smaller of the remaining elements in each buffer, and it follows that the index is only valid for the buffer with the larger number of remaining elements. Otherwise, there is no mismatch.
that
- The byte buffer to be tested for a mismatch with this 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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