java.nio.ByteBuffer

A byte buffer.

This class defines six categories of operations upon byte buffers:

Absolute and relative getandputmethods that read and write single bytes;

Relative bulk getmethods that transfer contiguous sequences of bytes from this buffer into an array;

Relative bulk putmethods that transfer contiguous sequences of bytes from a byte array or some other byte buffer into this buffer;

Absolute and relative getandputmethods that read and write values of other primitive types, translating them to and from sequences of bytes in a particular byte order;



    Methods for creating view buffers,
   which allow a byte buffer to be viewed as a buffer containing values of
   some other primitive type; and

Methods for compacting,duplicating, andslicinga byte buffer.

Byte buffers can be created either by allocation, which allocates space for the buffer's content, or by #wrap(byte[])wrappingan existing byte array into a buffer.

`Direct vs. non-direct buffers`



  A byte buffer is either direct or non-direct.  Given a
 direct byte buffer, the Java virtual machine will make a best effort to
 perform native I/O operations directly upon it.  That is, it will attempt to
 avoid copying the buffer's content to (or from) an intermediate buffer
 before (or after) each invocation of one of the underlying operating
 system's native I/O operations.

  A direct byte buffer may be created by invoking the #allocateDirect(int) allocateDirect
 factory method of this class.  The
 buffers returned by this method typically have somewhat higher allocation
 and deallocation costs than non-direct buffers.  The contents of direct
 buffers may reside outside of the normal garbage-collected heap, and so
 their impact upon the memory footprint of an application might not be
 obvious.  It is therefore recommended that direct buffers be allocated
 primarily for large, long-lived buffers that are subject to the underlying
 system's native I/O operations.  In general it is best to allocate direct
 buffers only when they yield a measureable gain in program performance.

A direct byte buffer may also be created by mappinga region of a file directly into memory. An implementation of the Java platform may optionally support the creation of direct byte buffers from native code via JNI. If an instance of one of these kinds of buffers refers to an inaccessible region of memory then an attempt to access that region will not change the buffer's content and will cause an unspecified exception to be thrown either at the time of the access or at some later time.

Whether a byte buffer is direct or non-direct may be determined by invoking its isDirect method. This method is provided so that explicit buffer management can be done in performance-critical code.

`Access to binary data`



  This class defines methods for reading and writing values of all other
 primitive types, except boolean.  Primitive values are translated
 to (or from) sequences of bytes according to the buffer's current byte
 order, which may be retrieved and modified via the order

 methods.  Specific byte orders are represented by instances of the ByteOrder
 class.  The initial order of a byte buffer is always BIG_ENDIAN
.

 
 For access to heterogeneous binary data, that is, sequences of values of
 different types, this class defines a family of absolute and relative
 get and put methods for each type.  For 32-bit floating-point
 values, for example, this class defines:

 
 float  #getFloat()

 float  #getFloat(int) getFloat(int index)

  void  #putFloat(float) putFloat(float f)

  void  


  Corresponding methods are defined for the types char,
 short, int, long, and double.  The index
 parameters of the absolute get and put methods are in terms of
 bytes rather than of the type being read or written.

 

 
 For access to homogeneous binary data, that is, sequences of values of
 the same type, this class defines methods that can create views of a
 given byte buffer.  A view buffer is simply another buffer whose
 content is backed by the byte buffer.  Changes to the byte buffer's content
 will be visible in the view buffer, and vice versa; the two buffers'
 position, limit, and mark values are independent.  The #asFloatBuffer() asFloatBuffer
 method, for example, creates an instance of
 the FloatBuffer
 class that is backed by the byte buffer upon which
 the method is invoked.  Corresponding view-creation methods are defined for
 the types char, short, int, long, and
 double.

 
 View buffers have three important advantages over the families of
 type-specific get and put methods described above:

 


    A view buffer is indexed not in terms of bytes but rather in terms
   of the type-specific size of its values;  

    A view buffer provides relative bulk get and put
   methods that can transfer contiguous sequences of values between a buffer
   and an array or some other buffer of the same type; and  

    A view buffer is potentially much more efficient because it will
   be direct if, and only if, its backing byte buffer is direct.  

 

  The byte order of a view buffer is fixed to be that of its byte buffer
 at the time that the view is created.  

























  Invocation chaining 


  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.



 The sequence of statements

 
 bb.putInt(0xCAFEBABE);
 bb.putShort(3);
 bb.putShort(45);

 can, for example, be replaced by the single statement

  bb.putInt(0xCAFEBABE).putShort(3).putShort(45);

@author
Mark Reinhold
@author
JSR-51 Expert Group
@version
1.56, 04/07/16
@since
1.4


Allocates a new byte buffer.

The new buffer's position will be zero, its limit will be its capacity, and its mark will be undefined. It will have abacking array, and itsarray offsetwill be zero.




Parameters

capacity
The new buffer's capacity, in bytes


Return
The new byte buffer


Throws

IllegalArgumentException
If the capacity is a negative integer


Allocates a new direct byte buffer.

The new buffer's position will be zero, its limit will be its capacity, and its mark will be undefined. Whether or not it has abacking arrayis unspecified.




Parameters

capacity
The new buffer's capacity, in bytes


Return
The new byte buffer


Throws

IllegalArgumentException
If the capacity is a negative integer




Returns the byte 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 view of this byte buffer as a char buffer.

  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 bytes remaining in this buffer divided by
 two, 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
A new char buffer





Creates a view of this byte buffer as a double buffer.

  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 bytes remaining in this buffer divided by
 eight, 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
A new double buffer





Creates a view of this byte buffer as a float buffer.

  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 bytes remaining in this buffer divided by
 four, 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
A new float buffer





Creates a view of this byte buffer as an int buffer.

  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 bytes remaining in this buffer divided by
 four, 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
A new int buffer





Creates a view of this byte buffer as a long buffer.

  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 bytes remaining in this buffer divided by
 eight, 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
A new long buffer





Creates a new, read-only byte 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 byte buffer





Creates a view of this byte buffer as a short buffer.

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



  Invoke this method after writing data from a buffer in case the
 write was incomplete.  The following loop, for example, copies bytes
 from one channel to another via the buffer buf:

 
 buf.clear();          // Prepare buffer for use
 for (;;) {
     if (in.read(buf) < 0 && !buf.hasRemaining())
         break;        // No more bytes to transfer
     buf.flip();
     out.write(buf);
     buf.compact();    // In case of partial write
 }


Return
This buffer


Throws

ReadOnlyBufferException
If this buffer is read-only





Compares this buffer to another.

  Two byte 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 byte 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

o the 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

ClassCastException if the specified object's type prevents it
         from being compared to this Object.





Creates a new byte 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 byte buffer





Tells whether or not this buffer is equal to another object.

  Two byte 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 byte buffer is not equal to any other type of object.  


Parameters

ob The 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 byte at this buffer's
 current position, and then increments the position. 


Return
The byte 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 bytes 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 bytes
          remaining in this buffer





Relative bulk get method.

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

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


Parameters

dst
The array into which bytes are to be written
offset
The offset within the array of the first byte to be
         written; must be non-negative and no larger than
         dst.length
length
The maximum number of bytes 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 bytes
          remaining in this buffer
IndexOutOfBoundsException
If the preconditions on the offset and length
          parameters do not hold





Absolute get method.  Reads the byte at the given
 index. 


Parameters

index
The index from which the byte will be read


Return
The byte at the given index


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit





Relative get method for reading a char value.

  Reads the next two bytes at this buffer's current position,
 composing them into a char value according to the current byte order,
 and then increments the position by two.  


Return
The char value at the buffer's current position


Throws

BufferUnderflowException
If there are fewer than two bytes
          remaining in this buffer





Absolute get method for reading a char value.

  Reads two bytes at the given index, composing them into a
 char value according to the current byte order.  


Parameters

index
The index from which the bytes will be read


Return
The char value at the given index


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus one





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.





Relative get method for reading a double value.

  Reads the next eight bytes at this buffer's current position,
 composing them into a double value according to the current byte order,
 and then increments the position by eight.  


Return
The double value at the buffer's current position


Throws

BufferUnderflowException
If there are fewer than eight bytes
          remaining in this buffer





Absolute get method for reading a double value.

  Reads eight bytes at the given index, composing them into a
 double value according to the current byte order.  


Parameters

index
The index from which the bytes will be read


Return
The double value at the given index


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus seven





Relative get method for reading a float value.

  Reads the next four bytes at this buffer's current position,
 composing them into a float value according to the current byte order,
 and then increments the position by four.  


Return
The float value at the buffer's current position


Throws

BufferUnderflowException
If there are fewer than four bytes
          remaining in this buffer





Absolute get method for reading a float value.

  Reads four bytes at the given index, composing them into a
 float value according to the current byte order.  


Parameters

index
The index from which the bytes will be read


Return
The float value at the given index


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus three





Relative get method for reading an int value.

  Reads the next four bytes at this buffer's current position,
 composing them into an int value according to the current byte order,
 and then increments the position by four.  


Return
The int value at the buffer's current position


Throws

BufferUnderflowException
If there are fewer than four bytes
          remaining in this buffer





Absolute get method for reading an int value.

  Reads four bytes at the given index, composing them into a
 int value according to the current byte order.  


Parameters

index
The index from which the bytes will be read


Return
The int value at the given index


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus three





Relative get method for reading a long value.

  Reads the next eight bytes at this buffer's current position,
 composing them into a long value according to the current byte order,
 and then increments the position by eight.  


Return
The long value at the buffer's current position


Throws

BufferUnderflowException
If there are fewer than eight bytes
          remaining in this buffer





Absolute get method for reading a long value.

  Reads eight bytes at the given index, composing them into a
 long value according to the current byte order.  


Parameters

index
The index from which the bytes will be read


Return
The long value at the given index


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus seven





Relative get method for reading a short value.

  Reads the next two bytes at this buffer's current position,
 composing them into a short value according to the current byte order,
 and then increments the position by two.  


Return
The short value at the buffer's current position


Throws

BufferUnderflowException
If there are fewer than two bytes
          remaining in this buffer





Absolute get method for reading a short value.

  Reads two bytes at the given index, composing them into a
 short value according to the current byte order.  


Parameters

index
The index from which the bytes will be read


Return
The short value at the given index


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus one





Tells whether or not this buffer is backed by an accessible byte
 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 byte 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 byte 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

IllegalMonitorStateException if the current thread is not
               the owner of this object's monitor.

See Also
java.lang.Object#notifyAll()
, java.lang.Object#wait()





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

IllegalMonitorStateException if the current thread is not
               the owner of this object's monitor.

See Also
java.lang.Object#notify()
, java.lang.Object#wait()





Retrieves this buffer's byte order.

  The byte order is used when reading or writing multibyte values, and
 when creating buffers that are views of this byte buffer.  The order of
 a newly-created byte buffer is always BIG_ENDIAN
.  


Return
This buffer's byte order





Modifies this buffer's byte order.  


Parameters

bo
The new byte order,
         either {@link ByteOrder#BIG_ENDIAN BIG_ENDIAN}
         or {@link ByteOrder#LITTLE_ENDIAN LITTLE_ENDIAN}


Return
This buffer





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 byte into this buffer at the current
 position, and then increments the position. 


Parameters

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

 
 Otherwise, this method copies length bytes 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 bytes are to be read
offset
The offset within the array of the first byte to be read;
         must be non-negative and no larger than array.length
length
The number of bytes 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 bytes remaining in the given source
 buffer into this buffer.  If there are more bytes remaining in the
 source buffer than in this buffer, that is, if
 src.remaining() > remaining(),
 then no bytes are transferred and a BufferOverflowException
 is thrown.

 
 Otherwise, this method copies
 n = src.remaining() bytes 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 bytes 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 bytes 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 byte into this buffer at the given
 index. 


Parameters

index
The index at which the byte will be written
b
The byte 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





Relative put method for writing a char
 value  (optional operation).

  Writes two bytes containing the given char value, in the
 current byte order, into this buffer at the current position, and then
 increments the position by two.  


Parameters

value
The char value to be written


Return
This buffer


Throws

BufferOverflowException
If there are fewer than two bytes
          remaining in this buffer
ReadOnlyBufferException
If this buffer is read-only





Absolute put method for writing a char
 value  (optional operation).

  Writes two bytes containing the given char value, in the
 current byte order, into this buffer at the given index.  


Parameters

index
The index at which the bytes will be written
value
The char value to be written


Return
This buffer


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus one
ReadOnlyBufferException
If this buffer is read-only





Relative put method for writing a double
 value  (optional operation).

  Writes eight bytes containing the given double value, in the
 current byte order, into this buffer at the current position, and then
 increments the position by eight.  


Parameters

value
The double value to be written


Return
This buffer


Throws

BufferOverflowException
If there are fewer than eight bytes
          remaining in this buffer
ReadOnlyBufferException
If this buffer is read-only





Absolute put method for writing a double
 value  (optional operation).

  Writes eight bytes containing the given double value, in the
 current byte order, into this buffer at the given index.  


Parameters

index
The index at which the bytes will be written
value
The double value to be written


Return
This buffer


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus seven
ReadOnlyBufferException
If this buffer is read-only





Relative put method for writing a float
 value  (optional operation).

  Writes four bytes containing the given float value, in the
 current byte order, into this buffer at the current position, and then
 increments the position by four.  


Parameters

value
The float value to be written


Return
This buffer


Throws

BufferOverflowException
If there are fewer than four bytes
          remaining in this buffer
ReadOnlyBufferException
If this buffer is read-only





Absolute put method for writing a float
 value  (optional operation).

  Writes four bytes containing the given float value, in the
 current byte order, into this buffer at the given index.  


Parameters

index
The index at which the bytes will be written
value
The float value to be written


Return
This buffer


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus three
ReadOnlyBufferException
If this buffer is read-only





Relative put method for writing an int
 value  (optional operation).

  Writes four bytes containing the given int value, in the
 current byte order, into this buffer at the current position, and then
 increments the position by four.  


Parameters

value
The int value to be written


Return
This buffer


Throws

BufferOverflowException
If there are fewer than four bytes
          remaining in this buffer
ReadOnlyBufferException
If this buffer is read-only





Absolute put method for writing an int
 value  (optional operation).

  Writes four bytes containing the given int value, in the
 current byte order, into this buffer at the given index.  


Parameters

index
The index at which the bytes will be written
value
The int value to be written


Return
This buffer


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus three
ReadOnlyBufferException
If this buffer is read-only





Absolute put method for writing a long
 value  (optional operation).

  Writes eight bytes containing the given long value, in the
 current byte order, into this buffer at the given index.  


Parameters

index
The index at which the bytes will be written
value
The long value to be written


Return
This buffer


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus seven
ReadOnlyBufferException
If this buffer is read-only





Relative put method for writing a long
 value  (optional operation).

  Writes eight bytes containing the given long value, in the
 current byte order, into this buffer at the current position, and then
 increments the position by eight.  


Parameters

value
The long value to be written


Return
This buffer


Throws

BufferOverflowException
If there are fewer than eight bytes
          remaining in this buffer
ReadOnlyBufferException
If this buffer is read-only





Absolute put method for writing a short
 value  (optional operation).

  Writes two bytes containing the given short value, in the
 current byte order, into this buffer at the given index.  


Parameters

index
The index at which the bytes will be written
value
The short value to be written


Return
This buffer


Throws

IndexOutOfBoundsException
If index is negative
          or not smaller than the buffer's limit,
          minus one
ReadOnlyBufferException
If this buffer is read-only





Relative put method for writing a short
 value  (optional operation).

  Writes two bytes containing the given short value, in the
 current byte order, into this buffer at the current position, and then
 increments the position by two.  


Parameters

value
The short value to be written


Return
This buffer


Throws

BufferOverflowException
If there are fewer than two bytes
          remaining in this buffer
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 byte 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 bytes 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 byte 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

IllegalMonitorStateException if the current thread is not
               the owner of the object's monitor.
InterruptedException if 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.

See Also
java.lang.Object#notify()
, java.lang.Object#notifyAll()





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

timeout the maximum time to wait in milliseconds.


Throws

IllegalArgumentException if the value of timeout is
		     negative.
IllegalMonitorStateException if the current thread is not
               the owner of the object's monitor.
InterruptedException if 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.

See Also
java.lang.Object#notify()
, java.lang.Object#notifyAll()





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

timeout the maximum time to wait in milliseconds.
nanos additional time, in nanoseconds range
                       0-999999.


Throws

IllegalArgumentException if the value of timeout is
			    negative or the value of nanos is
			    not in the range 0-999999.
IllegalMonitorStateException if the current thread is not
               the owner of this object's monitor.
InterruptedException if 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 byte array into a buffer.

The new buffer will be backed by the given byte 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. Itsbacking arraywill be the given array, and itsarray offsetwill be zero.




Parameters

array
The array that will back this buffer


Return
The new byte buffer


Wraps a byte array into a buffer.

The new buffer will be backed by the given byte 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. Itsbacking arraywill be the given array, and itsarray offsetwill 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 byte buffer


Throws

IndexOutOfBoundsException
If the preconditions on the offset and length
          parameters do not hold

ReadOnlyBufferException	If this buffer is backed by an array but is read-only
UnsupportedOperationException	If this buffer is not backed by an accessible array

dst	The array into which bytes are to be written
offset	The offset within the array of the first byte to be written; must be non-negative and no larger than `dst.length`
length	The maximum number of bytes 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` bytes remaining in this buffer
IndexOutOfBoundsException	If the preconditions on the `offset` and `length` parameters do not hold

BufferOverflowException	If this buffer's current position is not smaller than its limit
ReadOnlyBufferException	If this buffer is read-only

BufferOverflowException	If there is insufficient space in this buffer
ReadOnlyBufferException	If this buffer is read-only

src	The array from which bytes are to be read
offset	The offset within the array of the first byte to be read; must be non-negative and no larger than `array.length`
length	The number of bytes to be read from the given array; must be non-negative and no larger than `array.length - offset`

BufferOverflowException	If there is insufficient space in this buffer for the remaining bytes in the source buffer
IllegalArgumentException	If the source buffer is this buffer
ReadOnlyBufferException	If this buffer is read-only

index	The index at which the byte will be written
b	The byte value to be written

IndexOutOfBoundsException	If `index` is negative or not smaller than the buffer's limit
ReadOnlyBufferException	If this buffer is read-only

BufferOverflowException	If there are fewer than two bytes remaining in this buffer
ReadOnlyBufferException	If this buffer is read-only

index	The index at which the bytes will be written
value	The char value to be written

BufferOverflowException	If there are fewer than eight bytes remaining in this buffer
ReadOnlyBufferException	If this buffer is read-only

BufferOverflowException	If there are fewer than four bytes remaining in this buffer
ReadOnlyBufferException	If this buffer is read-only

IllegalMonitorStateException	if the current thread is not the owner of the object's monitor.
InterruptedException	if 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.

IllegalArgumentException	if the value of timeout is negative.
IllegalMonitorStateException	if the current thread is not the owner of the object's monitor.
InterruptedException	if 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.

timeout	the maximum time to wait in milliseconds.
nanos	additional time, in nanoseconds range 0-999999.

IllegalArgumentException	if the value of timeout is negative or the value of nanos is not in the range 0-999999.
IllegalMonitorStateException	if the current thread is not the owner of this object's monitor.
InterruptedException	if 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.

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`.