to top
Android APIs
public abstract class

FloatBuffer

extends Buffer
implements Comparable<T>
java.lang.Object
   ↳ java.nio.Buffer
     ↳ java.nio.FloatBuffer

Class Overview

A buffer of floats.

A float buffer can be created in either of the following ways:

  • Allocate a new float array and create a buffer based on it;
  • Wrap an existing float array to create a new buffer;
  • Use ByteBuffer.asFloatBuffer to create a float buffer based on a byte buffer.

Summary

Public Methods
static FloatBuffer allocate(int capacity)
Creates a float buffer based on a newly allocated float array.
final float[] array()
Returns the array that backs this buffer (optional operation).
final int arrayOffset()
Returns the offset into the array returned by array of the first element of the buffer (optional operation).
abstract FloatBuffer asReadOnlyBuffer()
Returns a read-only buffer that shares its content with this buffer.
abstract FloatBuffer compact()
Compacts this float buffer.
int compareTo(FloatBuffer otherBuffer)
Compare the remaining floats of this buffer to another float buffer's remaining floats.
abstract FloatBuffer duplicate()
Returns a duplicated buffer that shares its content with this buffer.
boolean equals(Object other)
Checks whether this float buffer is equal to another object.
abstract float get(int index)
Returns a float at the specified index; the position is not changed.
FloatBuffer get(float[] dst, int dstOffset, int floatCount)
Reads floats from the current position into the specified float array, starting from the specified offset, and increases the position by the number of floats read.
abstract float get()
Returns the float at the current position and increases the position by 1.
FloatBuffer get(float[] dst)
Reads floats from the current position into the specified float array and increases the position by the number of floats read.
final boolean hasArray()
Returns true if array and arrayOffset won't throw.
int hashCode()
Calculates this buffer's hash code from the remaining chars.
abstract boolean isDirect()
Indicates whether this buffer is direct.
abstract ByteOrder order()
Returns the byte order used by this buffer when converting floats from/to bytes.
abstract FloatBuffer put(int index, float f)
Writes a float to the specified index of this buffer; the position is not changed.
FloatBuffer put(float[] src, int srcOffset, int floatCount)
Writes floats from the given float array, starting from the specified offset, to the current position and increases the position by the number of floats written.
FloatBuffer put(FloatBuffer src)
Writes all the remaining floats of the src float buffer to this buffer's current position, and increases both buffers' position by the number of floats copied.
final FloatBuffer put(float[] src)
Writes floats from the given float array to the current position and increases the position by the number of floats written.
abstract FloatBuffer put(float f)
Writes the given float to the current position and increases the position by 1.
abstract FloatBuffer slice()
Returns a sliced buffer that shares its content with this buffer.
static FloatBuffer wrap(float[] array)
Creates a new float buffer by wrapping the given float array.
static FloatBuffer wrap(float[] array, int start, int floatCount)
Creates a new float buffer by wrapping the given float array.
[Expand]
Inherited Methods
From class java.nio.Buffer
From class java.lang.Object
From interface java.lang.Comparable

Public Methods

public static FloatBuffer allocate (int capacity)

Added in API level 1

Creates a float buffer based on a newly allocated float array.

Parameters
capacity the capacity of the new buffer.
Returns
  • the created float buffer.
Throws
IllegalArgumentException if capacity is less than zero.

public final float[] array ()

Added in API level 1

Returns the array that backs this buffer (optional operation). The returned value is the actual array, not a copy, so modifications to the array write through to the buffer.

Subclasses should override this method with a covariant return type to provide the exact type of the array.

Use hasArray to ensure this method won't throw. (A separate call to isReadOnly is not necessary.)

Returns
  • the array

public final int arrayOffset ()

Added in API level 1

Returns the offset into the array returned by array of the first element of the buffer (optional operation). The backing array (if there is one) is not necessarily the same size as the buffer, and position 0 in the buffer is not necessarily the 0th element in the array. Use buffer.array()[offset + buffer.arrayOffset() to access element offset in buffer.

Use hasArray to ensure this method won't throw. (A separate call to isReadOnly is not necessary.)

Returns
  • the offset

public abstract FloatBuffer asReadOnlyBuffer ()

Added in API level 1

Returns a read-only buffer that shares its content with this buffer.

The returned buffer is guaranteed to be a new instance, even if this buffer is read-only itself. The new buffer's position, limit, capacity and mark are the same as this buffer.

The new buffer shares its 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 read-only version of this buffer.

public abstract FloatBuffer compact ()

Added in API level 1

Compacts this float buffer.

The remaining floats will be moved to the head of the buffer, starting from position zero. Then the position is set to remaining(); the limit is set to capacity; the mark is cleared.

Returns
  • this buffer.
Throws
ReadOnlyBufferException if no changes may be made to the contents of this buffer.

public int compareTo (FloatBuffer otherBuffer)

Added in API level 1

Compare the remaining floats of this buffer to another float buffer's remaining floats.

Parameters
otherBuffer another float buffer.
Returns
  • a negative value if this is less than otherBuffer; 0 if this equals to otherBuffer; a positive value if this is greater than otherBuffer.
Throws
ClassCastException if otherBuffer is not a float buffer.

public abstract FloatBuffer duplicate ()

Added in API level 1

Returns a duplicated buffer that shares its content with this buffer.

The duplicated buffer's position, limit, capacity and mark are the same as this buffer. The duplicated buffer's read-only property and byte order are same as this buffer too.

The new buffer shares its content with this buffer, which means either buffer's change of content will be visible to the other. The two buffers' position, limit and mark are independent.

public boolean equals (Object other)

Added in API level 1

Checks whether this float buffer is equal to another object. If other is not a FloatBuffer then false is returned.

Two float buffers are equal if their remaining floats are equal. Position, limit, capacity and mark are not considered.

This method considers two floats a and b to be equal if a == b or if a and b are both NaN. Unlike equals(Object), this method considers -0.0 and +0.0 to be equal.

Parameters
other the object to compare with this float buffer.
Returns
  • true if this float buffer is equal to other, false otherwise.

public abstract float get (int index)

Added in API level 1

Returns a float at the specified index; the position is not changed.

Parameters
index the index, must not be negative and less than limit.
Returns
  • a float at the specified index.
Throws
IndexOutOfBoundsException if index is invalid.

public FloatBuffer get (float[] dst, int dstOffset, int floatCount)

Added in API level 1

Reads floats from the current position into the specified float array, starting from the specified offset, and increases the position by the number of floats read.

Parameters
dst the target float array.
dstOffset the offset of the float array, must not be negative and no greater than dst.length.
floatCount the number of floats to read, must be no less than zero and no greater than dst.length - dstOffset.
Returns
  • this buffer.
Throws
IndexOutOfBoundsException if either dstOffset or floatCount is invalid.
BufferUnderflowException if floatCount is greater than remaining().

public abstract float get ()

Added in API level 1

Returns the float at the current position and increases the position by 1.

Returns
  • the float at the current position.
Throws
BufferUnderflowException if the position is equal or greater than limit.

public FloatBuffer get (float[] dst)

Added in API level 1

Reads floats from the current position into the specified float array and increases the position by the number of floats read.

Calling this method has the same effect as get(dst, 0, dst.length).

Parameters
dst the destination float array.
Returns
  • this buffer.
Throws
BufferUnderflowException if dst.length is greater than remaining().

public final boolean hasArray ()

Added in API level 1

Returns true if array and arrayOffset won't throw. This method does not return true for buffers not backed by arrays because the other methods would throw UnsupportedOperationException, nor does it return true for buffers backed by read-only arrays, because the other methods would throw ReadOnlyBufferException.

public int hashCode ()

Added in API level 1

Calculates this buffer's hash code from the remaining chars. The position, limit, capacity and mark don't affect the hash code.

Returns
  • the hash code calculated from the remaining floats.

public abstract boolean isDirect ()

Added in API level 1

Indicates whether this buffer is direct. A direct buffer will try its best to take advantage of native memory APIs and it may not stay in the Java heap, so it is not affected by garbage collection.

A float buffer is direct if it is based on a byte buffer and the byte buffer is direct.

Returns
  • true if this buffer is direct, false otherwise.

public abstract ByteOrder order ()

Added in API level 1

Returns the byte order used by this buffer when converting floats from/to bytes.

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 floats from/to bytes.

public abstract FloatBuffer put (int index, float f)

Added in API level 1

Writes a float to the specified index of this buffer; the position is not changed.

Parameters
index the index, must not be negative and less than the limit.
f the float to write.
Returns
  • this buffer.
Throws
IndexOutOfBoundsException if index is invalid.
ReadOnlyBufferException if no changes may be made to the contents of this buffer.

public FloatBuffer put (float[] src, int srcOffset, int floatCount)

Added in API level 1

Writes floats from the given float array, starting from the specified offset, to the current position and increases the position by the number of floats written.

Parameters
src the source float array.
srcOffset the offset of float array, must not be negative and not greater than src.length.
floatCount the number of floats to write, must be no less than zero and no greater than src.length - srcOffset.
Returns
  • this buffer.
Throws
BufferOverflowException if remaining() is less than floatCount.
IndexOutOfBoundsException if either srcOffset or floatCount is invalid.
ReadOnlyBufferException if no changes may be made to the contents of this buffer.

public FloatBuffer put (FloatBuffer src)

Added in API level 1

Writes all the remaining floats of the src float buffer to this buffer's current position, and increases both buffers' position by the number of floats copied.

Parameters
src the source float buffer.
Returns
  • this buffer.
Throws
BufferOverflowException if src.remaining() is greater than this buffer's remaining().
IllegalArgumentException if src is this buffer.
ReadOnlyBufferException if no changes may be made to the contents of this buffer.

public final FloatBuffer put (float[] src)

Added in API level 1

Writes floats from the given float array to the current position and increases the position by the number of floats written.

Calling this method has the same effect as put(src, 0, src.length).

Parameters
src the source float array.
Returns
  • this buffer.
Throws
BufferOverflowException if remaining() is less than src.length.
ReadOnlyBufferException if no changes may be made to the contents of this buffer.

public abstract FloatBuffer put (float f)

Added in API level 1

Writes the given float to the current position and increases the position by 1.

Parameters
f the float to write.
Returns
  • this buffer.
Throws
BufferOverflowException if position is equal or greater than limit.
ReadOnlyBufferException if no changes may be made to the contents of this buffer.

public abstract FloatBuffer slice ()

Added in API level 1

Returns a sliced buffer that shares its 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 cleared. The new buffer's read-only property and byte order are same as this buffer's.

The new buffer shares its content with this buffer, which means either buffer's change of content will be visible to the other. The two buffers' position, limit and mark are independent.

public static FloatBuffer wrap (float[] array)

Added in API level 1

Creates a new float buffer by wrapping the given float array.

Calling this method has the same effect as wrap(array, 0, array.length).

Parameters
array the float array which the new buffer will be based on.
Returns
  • the created float buffer.

public static FloatBuffer wrap (float[] array, int start, int floatCount)

Added in API level 1

Creates a new float buffer by wrapping the given float array.

The new buffer's position will be start, limit will be start + floatCount, capacity will be the length of the array.

Parameters
array the float array which the new buffer will be based on.
start the start index, must not be negative and not greater than array.length.
floatCount the length, must not be negative and not greater than array.length - start.
Returns
  • the created float buffer.
Throws
IndexOutOfBoundsException if either start or floatCount is invalid.
NullPointerException if array is null.