Module java.base
Package java.nio

Class IntBuffer

  • All Implemented Interfaces:
    Comparable<IntBuffer>

    public abstract class IntBuffer
    extends Buffer
    implements Comparable<IntBuffer>
    An int buffer.

    This class defines four categories of operations upon int buffers:

    • Absolute and relative get and put methods that read and write single ints;

    • Relative bulk get methods that transfer contiguous sequences of ints from this buffer into an array; and

    • Relative bulk put methods that transfer contiguous sequences of ints from an int array or some other int buffer into this buffer; and

    • A method for compacting an int buffer.

    Int buffers can be created either by allocation, which allocates space for the buffer's content, by wrapping an existing int array into a buffer, or by creating a view of an existing byte buffer.

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

    Since:
    1.4
    • Method Detail

      • allocate

        public static IntBuffer allocate​(int capacity)
        Allocates a new int buffer.

        The new buffer's position will be zero, its limit will be its capacity, its mark will be undefined, each of its elements will be initialized to zero, and its byte order will be the native order of the underlying hardware. It will have a backing array, and its array offset will be zero.

        Parameters:
        capacity - The new buffer's capacity, in ints
        Returns:
        The new int buffer
        Throws:
        IllegalArgumentException - If the capacity is a negative integer
      • wrap

        public static IntBuffer wrap​(int[] array,
                                     int offset,
                                     int length)
        Wraps an int array into a buffer.

        The new buffer will be backed by the given int 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, its mark will be undefined, and its byte order will be the native order of the underlying hardware. 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.
        Returns:
        The new int buffer
        Throws:
        IndexOutOfBoundsException - If the preconditions on the offset and length parameters do not hold
      • wrap

        public static IntBuffer wrap​(int[] array)
        Wraps an int array into a buffer.

        The new buffer will be backed by the given int 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, its mark will be undefined, and its byte order will be the native order of the underlying hardware. Its backing array will be the given array, and its array offset will be zero.

        Parameters:
        array - The array that will back this buffer
        Returns:
        The new int buffer
      • slice

        public abstract IntBuffer slice()
        Creates a new int 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 ints remaining in this buffer, its mark will be undefined, and its byte order will be identical to that 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.

        Specified by:
        slice in class Buffer
        Returns:
        The new int buffer
      • duplicate

        public abstract IntBuffer duplicate()
        Creates a new int 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, mark values, and byte order 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.

        Specified by:
        duplicate in class Buffer
        Returns:
        The new int buffer
      • asReadOnlyBuffer

        public abstract IntBuffer asReadOnlyBuffer()
        Creates a new, read-only int 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, mark values, and byte order 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.

        Returns:
        The new, read-only int buffer
      • get

        public abstract int get()
        Relative get method. Reads the int at this buffer's current position, and then increments the position.
        Returns:
        The int at the buffer's current position
        Throws:
        BufferUnderflowException - If the buffer's current position is not smaller than its limit
      • put

        public abstract IntBuffer put​(int i)
        Relative put method  (optional operation).

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

        Parameters:
        i - The int to be written
        Returns:
        This buffer
        Throws:
        BufferOverflowException - If this buffer's current position is not smaller than its limit
        ReadOnlyBufferException - If this buffer is read-only
      • get

        public abstract int get​(int index)
        Absolute get method. Reads the int at the given index.
        Parameters:
        index - The index from which the int will be read
        Returns:
        The int at the given index
        Throws:
        IndexOutOfBoundsException - If index is negative or not smaller than the buffer's limit
      • put

        public abstract IntBuffer put​(int index,
                                      int i)
        Absolute put method  (optional operation).

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

        Parameters:
        index - The index at which the int will be written
        i - The int value to be written
        Returns:
        This buffer
        Throws:
        IndexOutOfBoundsException - If index is negative or not smaller than the buffer's limit
        ReadOnlyBufferException - If this buffer is read-only
      • get

        public IntBuffer get​(int[] dst,
                             int offset,
                             int length)
        Relative bulk get method.

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

        Otherwise, this method copies length ints 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 ints in this buffer and it is potentially much more efficient.
        Parameters:
        dst - The array into which ints are to be written
        offset - The offset within the array of the first int to be written; must be non-negative and no larger than dst.length
        length - The maximum number of ints to be written to the given array; must be non-negative and no larger than dst.length - offset
        Returns:
        This buffer
        Throws:
        BufferUnderflowException - If there are fewer than length ints remaining in this buffer
        IndexOutOfBoundsException - If the preconditions on the offset and length parameters do not hold
      • get

        public IntBuffer get​(int[] dst)
        Relative bulk get method.

        This method transfers ints 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) 
        Parameters:
        dst - The destination array
        Returns:
        This buffer
        Throws:
        BufferUnderflowException - If there are fewer than length ints remaining in this buffer
      • put

        public IntBuffer put​(IntBuffer src)
        Relative bulk put method  (optional operation).

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

        Otherwise, this method copies n = src.remaining() ints 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. If this buffer and the source buffer share the same backing array or memory, then the result will be as if the source elements were first copied to an intermediate location before being written into this buffer.
        Parameters:
        src - The source buffer from which ints are to be read; must not be this buffer
        Returns:
        This buffer
        Throws:
        BufferOverflowException - If there is insufficient space in this buffer for the remaining ints in the source buffer
        IllegalArgumentException - If the source buffer is this buffer
        ReadOnlyBufferException - If this buffer is read-only
      • put

        public IntBuffer put​(int[] src,
                             int offset,
                             int length)
        Relative bulk put method  (optional operation).

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

        Otherwise, this method copies length ints 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 ints are to be read
        offset - The offset within the array of the first int to be read; must be non-negative and no larger than array.length
        length - The number of ints to be read from the given array; must be non-negative and no larger than array.length - offset
        Returns:
        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
      • put

        public final IntBuffer put​(int[] src)
        Relative bulk put method  (optional operation).

        This method transfers the entire content of the given source int array into this buffer. An invocation of this method of the form dst.put(a) behaves in exactly the same way as the invocation

             dst.put(a, 0, a.length) 
        Parameters:
        src - The source array
        Returns:
        This buffer
        Throws:
        BufferOverflowException - If there is insufficient space in this buffer
        ReadOnlyBufferException - If this buffer is read-only
      • hasArray

        public final boolean hasArray()
        Tells whether or not this buffer is backed by an accessible int array.

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

        Specified by:
        hasArray in class Buffer
        Returns:
        true if, and only if, this buffer is backed by an array and is not read-only
      • array

        public final int[] array()
        Returns the int 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.

        Specified by:
        array in class Buffer
        Returns:
        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
      • arrayOffset

        public final int arrayOffset()
        Returns the offset within this buffer's backing array of the first element of the buffer  (optional operation).

        If this buffer is backed by an array then buffer position p corresponds to array index p + arrayOffset().

        Invoke the hasArray method before invoking this method in order to ensure that this buffer has an accessible backing array.

        Specified by:
        arrayOffset in class Buffer
        Returns:
        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
      • compact

        public abstract IntBuffer compact()
        Compacts this buffer  (optional operation).

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

        Returns:
        This buffer
        Throws:
        ReadOnlyBufferException - If this buffer is read-only
      • isDirect

        public abstract boolean isDirect()
        Tells whether or not this int buffer is direct.
        Specified by:
        isDirect in class Buffer
        Returns:
        true if, and only if, this buffer is direct
      • toString

        public String toString()
        Returns a string summarizing the state of this buffer.
        Overrides:
        toString in class Object
        Returns:
        A summary string
      • hashCode

        public int hashCode()
        Returns the current hash code of this buffer.

        The hash code of a int buffer depends only upon its remaining elements; that is, upon the elements from position() up to, and including, the element at limit() - 1.

        Because buffer hash codes are content-dependent, it is inadvisable to use buffers as keys in hash maps or similar data structures unless it is known that their contents will not change.

        Overrides:
        hashCode in class Object
        Returns:
        The current hash code of this buffer
        See Also:
        Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)
      • equals

        public boolean equals​(Object ob)
        Tells whether or not this buffer is equal to another object.

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

        Overrides:
        equals in class Object
        Parameters:
        ob - The object to which this buffer is to be compared
        Returns:
        true if, and only if, this buffer is equal to the given object
        See Also:
        Object.hashCode(), HashMap
      • compareTo

        public int compareTo​(IntBuffer that)
        Compares this buffer to another.

        Two int buffers are compared by comparing their sequences of remaining elements lexicographically, without regard to the starting position of each sequence within its corresponding buffer. Pairs of int elements are compared as if by invoking Integer.compare(int,int).

        A int buffer is not comparable to any other type of object.

        Specified by:
        compareTo in interface Comparable<IntBuffer>
        Parameters:
        that - the object to be compared.
        Returns:
        A negative integer, zero, or a positive integer as this buffer is less than, equal to, or greater than the given buffer
      • mismatch

        public int mismatch​(IntBuffer that)
        Finds and returns the relative index of the first mismatch between this buffer and a given buffer. The index is relative to the position of each buffer and will be in the range of 0 (inclusive) up to the smaller of the remaining elements in each buffer (exclusive).

        If the two buffers share a common prefix then the returned index is the length of the common prefix and it follows that there is a mismatch between the two buffers at that index within the respective buffers. If one buffer is a proper prefix of the other then the returned index is the smaller of the remaining elements in each buffer, and it follows that the index is only valid for the buffer with the larger number of remaining elements. Otherwise, there is no mismatch.

        Parameters:
        that - The byte buffer to be tested for a mismatch with this buffer
        Returns:
        The relative index of the first mismatch between this and the given buffer, otherwise -1 if no mismatch.
        Since:
        11
      • order

        public abstract ByteOrder order()
        Retrieves this buffer's byte order.

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

        Returns:
        This buffer's byte order