DoubleBuffer (Java Platform SE 8 ) (original) (raw)
Method Detail
* #### allocate
public static [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") allocate(int capacity)
Allocates a new double 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 [backing array](../../java/nio/DoubleBuffer.html#array--), and its [array offset](../../java/nio/DoubleBuffer.html#arrayOffset--) will be zero.
Parameters:
`capacity` \- The new buffer's capacity, in doubles
Returns:
The new double buffer
Throws:
`[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- If the capacity is a negative integer
* #### wrap
public static [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") wrap(double[] array,
int offset,
int length)
Wraps a double array into a buffer.
The new buffer will be backed by the given double array; that is, modifications to the buffer will cause the array to be modified and vice versa. The new buffer's capacity will bearray.length, its position will be offset, its limit will be offset + length, and its mark will be undefined. Its[backing array](../../java/nio/DoubleBuffer.html#array--) will be the given array, and its [array offset](../../java/nio/DoubleBuffer.html#arrayOffset--) will be zero.
Parameters:
`array` \- The array that will back the new buffer
`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.
`length` \- The length of the subarray to be used; must be non-negative and no larger thanarray.length - offset. The new buffer's limit will be set to offset + length.
Returns:
The new double buffer
Throws:
`[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")` \- If the preconditions on the offset and length parameters do not hold
* #### wrap
public static [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") wrap(double[] array)
Wraps a double array into a buffer.
The new buffer will be backed by the given double 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 bearray.length, its position will be zero, and its mark will be undefined. Its [backing array](../../java/nio/DoubleBuffer.html#array--) will be the given array, and its [array offset>](../../java/nio/DoubleBuffer.html#arrayOffset--) will be zero.
Parameters:
`array` \- The array that will back this buffer
Returns:
The new double buffer
* #### slice
public abstract [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") slice()
Creates a new double 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 doubles 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.
Returns:
The new double buffer
* #### duplicate
public abstract [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") duplicate()
Creates a new double 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.
Returns:
The new double buffer
* #### asReadOnlyBuffer
public abstract [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") asReadOnlyBuffer()
Creates a new, read-only double 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 [duplicate](../../java/nio/DoubleBuffer.html#duplicate--) method.
Returns:
The new, read-only double buffer
* #### get
public abstract double get()
Relative _get_ method. Reads the double at this buffer's current position, and then increments the position.
Returns:
The double at the buffer's current position
Throws:
`[BufferUnderflowException](../../java/nio/BufferUnderflowException.html "class in java.nio")` \- If the buffer's current position is not smaller than its limit
* #### put
public abstract [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") put(double d)
Relative _put_ method _(optional operation)_.
Writes the given double into this buffer at the current position, and then increments the position.
Parameters:
`d` \- The double to be written
Returns:
This buffer
Throws:
`[BufferOverflowException](../../java/nio/BufferOverflowException.html "class in java.nio")` \- If this buffer's current position is not smaller than its limit
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is read-only
* #### get
public abstract double get(int index)
Absolute _get_ method. Reads the double at the given index.
Parameters:
`index` \- The index from which the double will be read
Returns:
The double at the given index
Throws:
`[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")` \- If index is negative or not smaller than the buffer's limit
* #### put
public abstract [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") put(int index,
double d)
Absolute _put_ method _(optional operation)_.
Writes the given double into this buffer at the given index.
Parameters:
`index` \- The index at which the double will be written
`d` \- The double value to be written
Returns:
This buffer
Throws:
`[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")` \- If index is negative or not smaller than the buffer's limit
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is read-only
* #### get
public [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") get(double[] dst,
int offset,
int length)
Relative bulk _get_ method.
This method transfers doubles from this buffer into the given destination array. If there are fewer doubles remaining in the buffer than are required to satisfy the request, that is, iflength \> remaining(), then no doubles are transferred and a [BufferUnderflowException](../../java/nio/BufferUnderflowException.html "class in java.nio") is thrown.
Otherwise, this method copies length doubles 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 formsrc.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 doubles in this buffer and it is potentially much more efficient.
Parameters:
`dst` \- The array into which doubles are to be written
`offset` \- The offset within the array of the first double to be written; must be non-negative and no larger thandst.length
`length` \- The maximum number of doubles to be written to the given array; must be non-negative and no larger thandst.length - offset
Returns:
This buffer
Throws:
`[BufferUnderflowException](../../java/nio/BufferUnderflowException.html "class in java.nio")` \- If there are fewer than length doubles remaining in this buffer
`[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")` \- If the preconditions on the offset and length parameters do not hold
* #### get
public [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") get(double[] dst)
Relative bulk _get_ method.
This method transfers doubles from this buffer into the given destination array. An invocation of this method of the formsrc.get(a) behaves in exactly the same way as the invocation
src.get(a, 0, a.length)
Parameters:
`dst` \- The destination array
Returns:
This buffer
Throws:
`[BufferUnderflowException](../../java/nio/BufferUnderflowException.html "class in java.nio")` \- If there are fewer than length doubles remaining in this buffer
* #### put
public [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") put([DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") src)
Relative bulk _put_ method _(optional operation)_.
This method transfers the doubles remaining in the given source buffer into this buffer. If there are more doubles remaining in the source buffer than in this buffer, that is, ifsrc.remaining() \> remaining(), then no doubles are transferred and a [BufferOverflowException](../../java/nio/BufferOverflowException.html "class in java.nio") is thrown.
Otherwise, this method copies_n_ \= src.remaining() doubles 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 formdst.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.
Parameters:
`src` \- The source buffer from which doubles are to be read; must not be this buffer
Returns:
This buffer
Throws:
`[BufferOverflowException](../../java/nio/BufferOverflowException.html "class in java.nio")` \- If there is insufficient space in this buffer for the remaining doubles in the source buffer
`[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- If the source buffer is this buffer
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is read-only
* #### put
public [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") put(double[] src,
int offset,
int length)
Relative bulk _put_ method _(optional operation)_.
This method transfers doubles into this buffer from the given source array. If there are more doubles to be copied from the array than remain in this buffer, that is, iflength \> remaining(), then no doubles are transferred and a [BufferOverflowException](../../java/nio/BufferOverflowException.html "class in java.nio") is thrown.
Otherwise, this method copies length doubles 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 formdst.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.
Parameters:
`src` \- The array from which doubles are to be read
`offset` \- The offset within the array of the first double to be read; must be non-negative and no larger than array.length
`length` \- The number of doubles to be read from the given array; must be non-negative and no larger thanarray.length - offset
Returns:
This buffer
Throws:
`[BufferOverflowException](../../java/nio/BufferOverflowException.html "class in java.nio")` \- If there is insufficient space in this buffer
`[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")` \- If the preconditions on the offset and length parameters do not hold
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is read-only
* #### put
public final [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") put(double[] src)
Relative bulk _put_ method _(optional operation)_.
This method transfers the entire content of the given source double 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)
Parameters:
`src` \- The source array
Returns:
This buffer
Throws:
`[BufferOverflowException](../../java/nio/BufferOverflowException.html "class in java.nio")` \- If there is insufficient space in this buffer
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is read-only
* #### hasArray
public final boolean hasArray()
Tells whether or not this buffer is backed by an accessible double array.
If this method returns true then the [array](../../java/nio/DoubleBuffer.html#array--) and [arrayOffset](../../java/nio/DoubleBuffer.html#arrayOffset--) methods may safely be invoked.
Specified by:
`[hasArray](../../java/nio/Buffer.html#hasArray--)` in class `[Buffer](../../java/nio/Buffer.html "class in java.nio")`
Returns:
true if, and only if, this buffer is backed by an array and is not read-only
* #### array
public final double[] array()
Returns the double 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 [hasArray](../../java/nio/DoubleBuffer.html#hasArray--) method before invoking this method in order to ensure that this buffer has an accessible backing array.
Specified by:
`[array](../../java/nio/Buffer.html#array--)` in class `[Buffer](../../java/nio/Buffer.html "class in java.nio")`
Returns:
The array that backs this buffer
Throws:
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is backed by an array but is read-only
`[UnsupportedOperationException](../../java/lang/UnsupportedOperationException.html "class in java.lang")` \- If this buffer is not backed by an accessible array
* #### arrayOffset
public final int arrayOffset()
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 [hasArray](../../java/nio/DoubleBuffer.html#hasArray--) method before invoking this method in order to ensure that this buffer has an accessible backing array.
Specified by:
`[arrayOffset](../../java/nio/Buffer.html#arrayOffset--)` in class `[Buffer](../../java/nio/Buffer.html "class in java.nio")`
Returns:
The offset within this buffer's array of the first element of the buffer
Throws:
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is backed by an array but is read-only
`[UnsupportedOperationException](../../java/lang/UnsupportedOperationException.html "class in java.lang")` \- If this buffer is not backed by an accessible array
* #### compact
public abstract [DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") compact()
Compacts this buffer _(optional operation)_.
The doubles between the buffer's current position and its limit, if any, are copied to the beginning of the buffer. That is, the double at index _p_ \= position() is copied to index zero, the double at index _p_ \+ 1 is copied to index one, and so forth until the double at indexlimit() \- 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 doubles copied, rather than to zero, so that an invocation of this method can be followed immediately by an invocation of another relative _put_ method.
Returns:
This buffer
Throws:
`[ReadOnlyBufferException](../../java/nio/ReadOnlyBufferException.html "class in java.nio")` \- If this buffer is read-only
* #### isDirect
public abstract boolean isDirect()
Tells whether or not this double buffer is direct.
Specified by:
`[isDirect](../../java/nio/Buffer.html#isDirect--)` in class `[Buffer](../../java/nio/Buffer.html "class in java.nio")`
Returns:
true if, and only if, this buffer is direct
* #### toString
public [String](../../java/lang/String.html "class in java.lang") toString()
Returns a string summarizing the state of this buffer.
Overrides:
`[toString](../../java/lang/Object.html#toString--)` in class `[Object](../../java/lang/Object.html "class in java.lang")`
Returns:
A summary string
* #### hashCode
public int hashCode()
Returns the current hash code of this buffer.
The hash code of a double 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.
Overrides:
`[hashCode](../../java/lang/Object.html#hashCode--)` in class `[Object](../../java/lang/Object.html "class in java.lang")`
Returns:
The current hash code of this buffer
See Also:
[Object.equals(java.lang.Object)](../../java/lang/Object.html#equals-java.lang.Object-), [System.identityHashCode(java.lang.Object)](../../java/lang/System.html#identityHashCode-java.lang.Object-)
* #### equals
public boolean equals([Object](../../java/lang/Object.html "class in java.lang") ob)
Tells whether or not this buffer is equal to another object.
Two double buffers are equal if, and only if,
1. They have the same element type,
2. They have the same number of remaining elements, and
3. The two sequences of remaining elements, considered independently of their starting positions, are pointwise equal. This method considers two double elements `a` and `b` to be equal if`(a == b) || (Double.isNaN(a) && Double.isNaN(b))`. The values `-0.0` and `+0.0` are considered to be equal, unlike [Double.equals(Object)](../../java/lang/Double.html#equals-java.lang.Object-).
A double buffer is not equal to any other type of object.
Overrides:
`[equals](../../java/lang/Object.html#equals-java.lang.Object-)` in class `[Object](../../java/lang/Object.html "class in java.lang")`
Parameters:
`ob` \- The object to which this buffer is to be compared
Returns:
true if, and only if, this buffer is equal to the given object
See Also:
[Object.hashCode()](../../java/lang/Object.html#hashCode--), [HashMap](../../java/util/HashMap.html "class in java.util")
* #### compareTo
public int compareTo([DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio") that)
Compares this buffer to another.
Two double 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 `double` elements are compared as if by invoking[Double.compare(double,double)](../../java/lang/Double.html#compare-double-double-), except that`-0.0` and `0.0` are considered to be equal.`Double.NaN` is considered by this method to be equal to itself and greater than all other `double` values (including `Double.POSITIVE_INFINITY`).
A double buffer is not comparable to any other type of object.
Specified by:
`[compareTo](../../java/lang/Comparable.html#compareTo-T-)` in interface `[Comparable](../../java/lang/Comparable.html "interface in java.lang")<[DoubleBuffer](../../java/nio/DoubleBuffer.html "class in java.nio")>`
Parameters:
`that` \- the object to be compared.
Returns:
A negative integer, zero, or a positive integer as this buffer is less than, equal to, or greater than the given buffer
* #### order
public abstract [ByteOrder](../../java/nio/ByteOrder.html "class in java.nio") order()
Retrieves this buffer's byte order.
The byte order of a double buffer created by allocation or by wrapping an existing double array is the [native order](../../java/nio/ByteOrder.html#nativeOrder--) of the underlying hardware. The byte order of a double buffer created as a [view](ByteBuffer.html#views) of a byte buffer is that of the byte buffer at the moment that the view is created.
Returns:
This buffer's byte order