java.nio
public
abstract
class
java.nio.DoubleBuffer
A buffer of double
s.
A double buffer can be created in either of the following ways:
- Allocate a new double array and create a buffer
based on it;
- Wrap an existing double array to create a new
buffer;
- Use
ByteBuffer.asDoubleBuffer to
create a double buffer based on a byte buffer.
Summary
Public Methods
capacity,
clear,
flip,
hasRemaining,
isReadOnly,
limit,
limit,
mark,
position,
position,
remaining,
reset,
rewind
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
Details
Public Methods
public
static
DoubleBuffer
allocate(int capacity)
Creates a double buffer based on a new allocated double array.
Parameters
capacity
| The capacity of the new buffer |
Returns
- The created double buffer
public
final
double[]
array()
Returns the double array which this buffer is based on, if there's one.
Returns
- The double array which this buffer is based on
public
final
int
arrayOffset()
Returns the offset of the double array which this buffer is based on, if
there's one.
The offset is the index of the array corresponds to the zero position of
the buffer.
Returns
- The offset of the double array which this buffer is based on
public
abstract
DoubleBuffer
asReadOnlyBuffer()
Returns a readonly buffer that shares content with this buffer.
The returned buffer is guaranteed to be a new instance, even this
buffer is readonly itself. The new buffer's position, limit, capacity
and mark are the same as this buffer.
The new buffer shares content with this buffer, which means
this buffer's change of content will be visible to the new buffer.
The two buffer's position, limit and mark are independent.
Returns
- A readonly version of this buffer.
public
abstract
DoubleBuffer
compact()
Compacts this double buffer.
The remaining double
s will be moved to the head of the
buffer, staring from position zero. Then the position is set to
remaining()
; the limit is set to capacity; the mark is
cleared.
public
int
compareTo(DoubleBuffer otherBuffer)
Compare the remaining
double
s of this buffer to another
double buffer's remaining
double
s.
Parameters
otherBuffer
| Another double buffer |
Returns
- a negative value if this is less than
other
; 0 if
this equals to other
; a positive value if this is
greater than other
public
abstract
DoubleBuffer
duplicate()
Returns a duplicated buffer that shares content with this buffer.
The duplicated buffer's position, limit, capacity and mark are the
same as this buffer. The duplicated buffer's readonly property and
byte order are same as this buffer too.
The new buffer shares content with this buffer, which means
either buffer's change of content will be visible to the other.
The two buffer's position, limit and mark are independent.
Returns
- A duplicated buffer that shares content with this buffer.
public
boolean
equals(Object other)
Tests whether this double buffer equals to another object.
If other
is not a double buffer, then false is returned.
Two double buffers are equals if, and only if, their remaining
double
s are exactly the same. Position, limit, capacity and
mark are not considered.
Parameters
other
| the object to be compared against |
Returns
- Whether this double buffer equals to another object.
public
abstract
double
get()
Returns the double at the current position and increase the position by 1.
Returns
- The double at the current position.
public
abstract
double
get(int index)
Returns a double at the specified index, and the position is not changed.
Parameters
index
| The index, must be no less than zero and less than limit |
Returns
- A double at the specified index.
public
DoubleBuffer
get(double[] dest, int off, int len)
Reads
double
s from the current position into the
specified double array, starting from the specified offset, and increase
the position by the number of
double
s read.
Parameters
dest
| The target double array |
off
| The offset of the double array, must be no less than zero and
no greater than dest.length |
len
| The number of double s to read, must be no less
than zero and no greater than dest.length - off |
public
DoubleBuffer
get(double[] dest)
Reads
double
s from the current position into the
specified double array and increase the position by the number of
double
s read.
Calling this method has the same effect as
get(dest, 0, dest.length)
.
Parameters
dest
| The destination double array |
public
final
boolean
hasArray()
Returns whether this buffer is based on a double array and is read/write.
If this buffer is readonly, then false is returned.
Returns
- Whether this buffer is based on a double array and is read/write.
public
int
hashCode()
Hash code is calculated from the remaining
double
s.
Position, limit, capacity and mark don't affect the hash code.
Returns
- The hash code calculated from the remaining
double
s.
public
abstract
boolean
isDirect()
Returns true if this buffer is direct.
A direct buffer will try its best to take advantage of native memory
APIs and it may not stay in java heap, thus not affected by GC.
A double buffer is direct, if it is based on a byte buffer and the byte
buffer is direct.
Returns
- True if this buffer is direct.
public
abstract
ByteOrder
order()
Returns the byte order used by this buffer when converting
double
s from/to
byte
s.
If this buffer is not based on a byte buffer, then always return the
platform's native byte order.
Returns
- The byte order used by this buffer when converting
double
s from/to byte
s.
public
final
DoubleBuffer
put(double[] src)
Writes
double
s in the given double array to the current
position and increase the position by the number of
double
s
written.
Calling this method has the same effect as
put(src, 0, src.length)
.
Parameters
src
| The source double array |
Writes all the remaining
double
s of the
src
double buffer to this buffer's current position, and increase both
buffers' position by the number of
double
s copied.
Parameters
src
| The source double buffer |
public
abstract
DoubleBuffer
put(int index, double d)
Write a double to the specified index of this buffer and the position is
not changed.
Parameters
index
| The index, must be no less than zero and less than the limit |
d
| The double to write |
public
abstract
DoubleBuffer
put(double d)
Writes the given double to the current position and increase the position
by 1.
public
DoubleBuffer
put(double[] src, int off, int len)
Writes
double
s in the given double array, starting from
the specified offset, to the current position and increase the position
by the number of
double
s written.
Parameters
src
| The source double array |
off
| The offset of double array, must be no less than zero and no
greater than src.length |
len
| The number of double s to write, must be no
less than zero and no greater than
src.length - off |
Returns a sliced buffer that shares content with this buffer.
The sliced buffer's capacity will be this buffer's
remaining()
, and its zero position will correspond to
this buffer's current position. The new buffer's position will be
0, limit will be its capacity, and its mark is unset. The new buffer's
readonly property and byte order are same as this buffer.
The new buffer shares content with this buffer, which means
either buffer's change of content will be visible to the other.
The two buffer's position, limit and mark are independent.
Returns
- A sliced buffer that shares content with this buffer.
public
String
toString()
Returns a string represents the state of this double buffer.
Returns
- A string represents the state of this double buffer.
public
static
DoubleBuffer
wrap(double[] array, int start, int len)
Creates new a double buffer by wrapping the given double array.
The new buffer's position will be start
, limit will be
start + len
, capacity will be the length of the array.
Parameters
array
| The double array which the new buffer will be based on |
start
| The start index, must be no less than zero and no greater than
array.length |
len
| The length, must be no less than zero and no greater than
array.length - start |
Returns
- The created double buffer
public
static
DoubleBuffer
wrap(double[] array)
Creates a new double buffer by wrapping the given double array.
Calling this method has the same effect as
wrap(array, 0, array.length)
.
Parameters
array
| The double array which the new buffer will be based on |
Returns
- The created double buffer