A float buffer.

This class defines four categories of operations upon float buffers:

Float buffers can be created either by allocation , which allocates space for the buffer's content, by #wrap(float[]) wrapping an existing float array into a buffer, or by creating a view of an existing byte buffer

Like a byte buffer, a float buffer is either direct or non-direct. A float buffer created via the wrap methods of this class will be non-direct. A float 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 float 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.

@author
Mark Reinhold
@author
JSR-51 Expert Group
@version
1.56, 04/07/16
@since
1.4
Allocates a new float buffer.

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.

Parameters
capacity The new buffer's capacity, in floats
Return
The new float buffer
Throws
IllegalArgumentException If the capacity is a negative integer
Returns the float 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 method before invoking this method in order to ensure that this buffer has an accessible backing array.

Return
The array that backs this buffer
Throws
ReadOnlyBufferException If this buffer is backed by an array but is read-only
UnsupportedOperationException If this buffer is not backed by an accessible array
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 method before invoking this method in order to ensure that this buffer has an accessible backing array.

Return
The offset within this buffer's array of the first element of the buffer
Throws
ReadOnlyBufferException If this buffer is backed by an array but is read-only
UnsupportedOperationException If this buffer is not backed by an accessible array
Creates a new, read-only float 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 method.

Return
The new, read-only float buffer
Returns this buffer's capacity.

Return
The capacity of this buffer
Clears this buffer. The position is set to zero, the limit is set to the capacity, and the mark is discarded.

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.

Return
This buffer
Compacts this buffer  (optional operation).

The floats between the buffer's current position and its limit, if any, are copied to the beginning of the buffer. That is, the float at index p = position() is copied to index zero, the float at index p + 1 is copied to index one, and so forth until the float 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 floats copied, rather than to zero, so that an invocation of this method can be followed immediately by an invocation of another relative put method.

Return
This buffer
Throws
ReadOnlyBufferException If this buffer is read-only
Compares this buffer to another.

Two float 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 float buffer is not comparable to any other type of object.

Return
A negative integer, zero, or a positive integer as this buffer is less than, equal to, or greater than the given buffer
Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

In the foregoing description, the notation sgn(expression) designates the mathematical signum function, which is defined to return one of -1, 0, or 1 according to whether the value of expression is negative, zero or positive. The implementor must ensure sgn(x.compareTo(y)) == -sgn(y.compareTo(x)) for all x and y. (This implies that x.compareTo(y) must throw an exception iff y.compareTo(x) throws an exception.)

The implementor must also ensure that the relation is transitive: (x.compareTo(y)>0 && y.compareTo(z)>0) implies x.compareTo(z)>0.

Finally, the implementer must ensure that x.compareTo(y)==0 implies that sgn(x.compareTo(z)) == sgn(y.compareTo(z)), for all z.

It is strongly recommended, but not strictly required that (x.compareTo(y)==0) == (x.equals(y)). Generally speaking, any class that implements the Comparable interface and violates this condition should clearly indicate this fact. The recommended language is "Note: this class has a natural ordering that is inconsistent with equals."

Parameters
othe Object to be compared.
Return
a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.
Throws
ClassCastExceptionif the specified object's type prevents it from being compared to this Object.
Creates a new float 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.

Return
The new float buffer
Tells whether or not this buffer is equal to another object.

Two float 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.

A float buffer is not equal to any other type of object.

Parameters
obThe object to which this buffer is to be compared
Return
true if, and only if, this buffer is equal to the given object
Flips this buffer. The limit is set to the current position and then the position is set to zero. If the mark is defined then it is discarded.

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.

Return
This buffer
Relative get method. Reads the float at this buffer's current position, and then increments the position.

Return
The float at the buffer's current position
Throws
BufferUnderflowException If the buffer's current position is not smaller than its limit
Relative bulk get method.

This method transfers floats 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) 
Return
This buffer
Throws
BufferUnderflowException If there are fewer than length floats remaining in this buffer
Relative bulk get method.

This method transfers floats from this buffer into the given destination array. If there are fewer floats remaining in the buffer than are required to satisfy the request, that is, if length > remaining(), then no floats are transferred and a BufferUnderflowException is thrown.

Otherwise, this method copies length floats 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 floats in this buffer and it is potentially much more efficient.

Parameters
dst The array into which floats are to be written
offset The offset within the array of the first float to be written; must be non-negative and no larger than dst.length
length The maximum number of floats to be written to the given array; must be non-negative and no larger than dst.length - offset
Return
This buffer
Throws
BufferUnderflowException If there are fewer than length floats remaining in this buffer
IndexOutOfBoundsException If the preconditions on the offset and length parameters do not hold
Absolute get method. Reads the float at the given index.

Parameters
index The index from which the float will be read
Return
The float at the given index
Throws
IndexOutOfBoundsException If index is negative or not smaller than the buffer's limit
Returns the runtime class of an object. That Class object is the object that is locked by static synchronized methods of the represented class.
Return
The java.lang.Class object that represents the runtime class of the object. The result is of type {@code Class} where X is the erasure of the static type of the expression on which getClass is called.
Tells whether or not this buffer is backed by an accessible float array.

If this method returns true then the array and arrayOffset methods may safely be invoked.

Return
true if, and only if, this buffer is backed by an array and is not read-only
Returns the current hash code of this buffer.

The hash code of a float 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.

Return
The current hash code of this buffer
Tells whether there are any elements between the current position and the limit.

Return
true if, and only if, there is at least one element remaining in this buffer
Tells whether or not this float buffer is direct.

Return
true if, and only if, this buffer is direct
Tells whether or not this buffer is read-only.

Return
true if, and only if, this buffer is read-only
Returns this buffer's limit.

Return
The limit of this buffer
Sets this buffer's limit. If the position is larger than the new limit then it is set to the new limit. If the mark is defined and larger than the new limit then it is discarded.

Parameters
newLimit The new limit value; must be non-negative and no larger than this buffer's capacity
Return
This buffer
Throws
IllegalArgumentException If the preconditions on newLimit do not hold
Sets this buffer's mark at its position.

Return
This buffer
Wakes up a single thread that is waiting on this object's monitor. If any threads are waiting on this object, one of them is chosen to be awakened. The choice is arbitrary and occurs at the discretion of the implementation. A thread waits on an object's monitor by calling one of the wait methods.

The awakened thread will not be able to proceed until the current thread relinquishes the lock on this object. The awakened thread will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened thread enjoys no reliable privilege or disadvantage in being the next thread to lock this object.

This method should only be called by a thread that is the owner of this object's monitor. A thread becomes the owner of the object's monitor in one of three ways:

  • By executing a synchronized instance method of that object.
  • By executing the body of a synchronized statement that synchronizes on the object.
  • For objects of type Class, by executing a synchronized static method of that class.

Only one thread at a time can own an object's monitor.

Throws
IllegalMonitorStateExceptionif the current thread is not the owner of this object's monitor.
Wakes up all threads that are waiting on this object's monitor. A thread waits on an object's monitor by calling one of the wait methods.

The awakened threads will not be able to proceed until the current thread relinquishes the lock on this object. The awakened threads will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened threads enjoy no reliable privilege or disadvantage in being the next thread to lock this object.

This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.

Throws
IllegalMonitorStateExceptionif the current thread is not the owner of this object's monitor.
Retrieves this buffer's byte order.

The byte order of a float buffer created by allocation or by wrapping an existing float array is the native order of the underlying hardware. The byte order of a float buffer created as a view of a byte buffer is that of the byte buffer at the moment that the view is created.

Return
This buffer's byte order
Returns this buffer's position.

Return
The position of this buffer
Sets this buffer's position. If the mark is defined and larger than the new position then it is discarded.

Parameters
newPosition The new position value; must be non-negative and no larger than the current limit
Return
This buffer
Throws
IllegalArgumentException If the preconditions on newPosition do not hold
Relative put method  (optional operation).

Writes the given float into this buffer at the current position, and then increments the position.

Parameters
f The float to be written
Return
This buffer
Throws
BufferOverflowException If this buffer's current position is not smaller than its limit
ReadOnlyBufferException If this buffer is read-only
Relative bulk put method  (optional operation).

This method transfers the entire content of the given source float 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) 
Return
This buffer
Throws
BufferOverflowException If there is insufficient space in this buffer
ReadOnlyBufferException If this buffer is read-only
Relative bulk put method  (optional operation).

This method transfers floats into this buffer from the given source array. If there are more floats to be copied from the array than remain in this buffer, that is, if length > remaining(), then no floats are transferred and a BufferOverflowException is thrown.

Otherwise, this method copies length floats 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.

Parameters
src The array from which floats are to be read
offset The offset within the array of the first float to be read; must be non-negative and no larger than array.length
length The number of floats to be read from the given array; must be non-negative and no larger than array.length - offset
Return
This buffer
Throws
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-only
Relative bulk put method  (optional operation).

This method transfers the floats remaining in the given source buffer into this buffer. If there are more floats remaining in the source buffer than in this buffer, that is, if src.remaining() > remaining(), then no floats are transferred and a BufferOverflowException is thrown.

Otherwise, this method copies n = src.remaining() floats 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.

Parameters
src The source buffer from which floats are to be read; must not be this buffer
Return
This buffer
Throws
BufferOverflowException If there is insufficient space in this buffer for the remaining floats in the source buffer
IllegalArgumentException If the source buffer is this buffer
ReadOnlyBufferException If this buffer is read-only
Absolute put method  (optional operation).

Writes the given float into this buffer at the given index.

Parameters
index The index at which the float will be written
f The float value to be written
Return
This buffer
Throws
IndexOutOfBoundsException If index is negative or not smaller than the buffer's limit
ReadOnlyBufferException If this buffer is read-only
Returns the number of elements between the current position and the limit.

Return
The number of elements remaining in this buffer
Resets this buffer's position to the previously-marked position.

Invoking this method neither changes nor discards the mark's value.

Return
This buffer
Throws
InvalidMarkException If the mark has not been set
Rewinds this buffer. The position is set to zero and the mark is discarded.

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
Return
This buffer
Creates a new float 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 floats 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.

Return
The new float buffer
Returns a string summarizing the state of this buffer.

Return
A summary string
Causes current thread to wait until another thread invokes the method or the method for this object. In other words, this method behaves exactly as if it simply performs the call wait(0).

The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until another thread notifies threads waiting on this object's monitor to wake up either through a call to the notify method or the notifyAll method. The thread then waits until it can re-obtain ownership of the monitor and resumes execution.

As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:

     synchronized (obj) {
         while (<condition does not hold>)
             obj.wait();
         ... // Perform action appropriate to condition
     }
 
This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.
Throws
IllegalMonitorStateExceptionif the current thread is not the owner of the object's monitor.
InterruptedExceptionif another thread interrupted the current thread before or while the current thread was waiting for a notification. The interrupted status of the current thread is cleared when this exception is thrown.
Causes current thread to wait until either another thread invokes the method or the method for this object, or a specified amount of time has elapsed.

The current thread must own this object's monitor.

This method causes the current thread (call it T) to place itself in the wait set for this object and then to relinquish any and all synchronization claims on this object. Thread T becomes disabled for thread scheduling purposes and lies dormant until one of four things happens:

  • Some other thread invokes the notify method for this object and thread T happens to be arbitrarily chosen as the thread to be awakened.
  • Some other thread invokes the notifyAll method for this object.
  • Some other thread interrupts thread T.
  • The specified amount of real time has elapsed, more or less. If timeout is zero, however, then real time is not taken into consideration and the thread simply waits until notified.
The thread T is then removed from the wait set for this object and re-enabled for thread scheduling. It then competes in the usual manner with other threads for the right to synchronize on the object; once it has gained control of the object, all its synchronization claims on the object are restored to the status quo ante - that is, to the situation as of the time that the wait method was invoked. Thread T then returns from the invocation of the wait method. Thus, on return from the wait method, the synchronization state of the object and of thread T is exactly as it was when the wait method was invoked.

A thread can also wake up without being notified, interrupted, or timing out, a so-called spurious wakeup. While this will rarely occur in practice, applications must guard against it by testing for the condition that should have caused the thread to be awakened, and continuing to wait if the condition is not satisfied. In other words, waits should always occur in loops, like this one:

     synchronized (obj) {
         while (<condition does not hold>)
             obj.wait(timeout);
         ... // Perform action appropriate to condition
     }
 
(For more information on this topic, see Section 3.2.3 in Doug Lea's "Concurrent Programming in Java (Second Edition)" (Addison-Wesley, 2000), or Item 50 in Joshua Bloch's "Effective Java Programming Language Guide" (Addison-Wesley, 2001).

If the current thread is interrupted by another thread while it is waiting, then an InterruptedException is thrown. This exception is not thrown until the lock status of this object has been restored as described above.

Note that the wait method, as it places the current thread into the wait set for this object, unlocks only this object; any other objects on which the current thread may be synchronized remain locked while the thread waits.

This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.

Parameters
timeoutthe maximum time to wait in milliseconds.
Throws
IllegalArgumentExceptionif the value of timeout is negative.
IllegalMonitorStateExceptionif the current thread is not the owner of the object's monitor.
InterruptedExceptionif another thread interrupted the current thread before or while the current thread was waiting for a notification. The interrupted status of the current thread is cleared when this exception is thrown.
Causes current thread to wait until another thread invokes the method or the method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.

This method is similar to the wait method of one argument, but it allows finer control over the amount of time to wait for a notification before giving up. The amount of real time, measured in nanoseconds, is given by:

 1000000*timeout+nanos

In all other respects, this method does the same thing as the method of one argument. In particular, wait(0, 0) means the same thing as wait(0).

The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until either of the following two conditions has occurred:

  • Another thread notifies threads waiting on this object's monitor to wake up either through a call to the notify method or the notifyAll method.
  • The timeout period, specified by timeout milliseconds plus nanos nanoseconds arguments, has elapsed.

The thread then waits until it can re-obtain ownership of the monitor and resumes execution.

As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:

     synchronized (obj) {
         while (<condition does not hold>)
             obj.wait(timeout, nanos);
         ... // Perform action appropriate to condition
     }
 
This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.
Parameters
timeoutthe maximum time to wait in milliseconds.
nanosadditional time, in nanoseconds range 0-999999.
Throws
IllegalArgumentExceptionif the value of timeout is negative or the value of nanos is not in the range 0-999999.
IllegalMonitorStateExceptionif the current thread is not the owner of this object's monitor.
InterruptedExceptionif another thread interrupted the current thread before or while the current thread was waiting for a notification. The interrupted status of the current thread is cleared when this exception is thrown.
Wraps a float array into a buffer.

The new buffer will be backed by the given float 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.

Parameters
array The array that will back this buffer
Return
The new float buffer
Wraps a float array into a buffer.

The new buffer will be backed by the given float 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.

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 than array.length - offset. The new buffer's limit will be set to offset + length.
Return
The new float buffer
Throws
IndexOutOfBoundsException If the preconditions on the offset and length parameters do not hold