BufferUtil (Agrona)

java.lang.Object
- org.agrona.BufferUtil

public final class BufferUtil
extends Object

Common functions for buffer implementations.

Field Summary

Fields
Modifier and Type	Field and Description
`static long`	`ARRAY_BASE_OFFSET` Byte array base offset.
`static long`	`BYTE_BUFFER_ADDRESS_FIELD_OFFSET` Offset of the `java.nio.Buffer#address` field.
`static long`	`BYTE_BUFFER_HB_FIELD_OFFSET` Offset of the `java.nio.ByteBuffer#hb` field.
`static long`	`BYTE_BUFFER_OFFSET_FIELD_OFFSET` Offset of the `java.nio.ByteBuffer#offset` field.
`static ByteOrder`	`NATIVE_BYTE_ORDER` Native byte order.
`static byte[]`	`NULL_BYTES` UTF-8-encoded byte representation of the `"null"` string.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static long`	`address(ByteBuffer buffer)` Get the address at which the underlying buffer storage begins.
`static ByteBuffer`	`allocateDirectAligned(int capacity, int alignment)` Allocate a new direct `ByteBuffer` that is aligned on a given alignment boundary.
`static byte[]`	`array(ByteBuffer buffer)` Get the array from a read-only `ByteBuffer` similar to `ByteBuffer.array()`.
`static int`	`arrayOffset(ByteBuffer buffer)` Get the array offset from a read-only `ByteBuffer` similar to `ByteBuffer.arrayOffset()`.
`static void`	`boundsCheck(byte[] buffer, long index, int length)` Bounds check the access range and throw a `IndexOutOfBoundsException` if exceeded.
`static void`	`boundsCheck(ByteBuffer buffer, long index, int length)` Bounds check the access range and throw a `IndexOutOfBoundsException` if exceeded.
`static void`	`free(ByteBuffer buffer)` Free direct `ByteBuffer` by invoking `Cleaner` on it.
`static void`	`free(DirectBuffer buffer)` Free the underlying direct `ByteBuffer` by invoking `Cleaner` on it.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - NULL_BYTES
```
public static final byte[] NULL_BYTES
```
    UTF-8-encoded byte representation of the "null" string.
  - NATIVE_BYTE_ORDER
```
public static final ByteOrder NATIVE_BYTE_ORDER
```
    Native byte order.
  - ARRAY_BASE_OFFSET
```
public static final long ARRAY_BASE_OFFSET
```
    Byte array base offset.
  - BYTE_BUFFER_HB_FIELD_OFFSET
```
public static final long BYTE_BUFFER_HB_FIELD_OFFSET
```
    Offset of the java.nio.ByteBuffer#hb field.
  - BYTE_BUFFER_OFFSET_FIELD_OFFSET
```
public static final long BYTE_BUFFER_OFFSET_FIELD_OFFSET
```
    Offset of the java.nio.ByteBuffer#offset field.
  - BYTE_BUFFER_ADDRESS_FIELD_OFFSET
```
public static final long BYTE_BUFFER_ADDRESS_FIELD_OFFSET
```
    Offset of the java.nio.Buffer#address field.
- Method Detail
  - boundsCheck
```
public static void boundsCheck(byte[] buffer,
                               long index,
                               int length)
```
    Bounds check the access range and throw a IndexOutOfBoundsException if exceeded.
    
    Parameters:
    
    buffer - to be checked.
    
    index - at which the access will begin.
    
    length - of the range accessed.
  - boundsCheck
```
public static void boundsCheck(ByteBuffer buffer,
                               long index,
                               int length)
```
    Bounds check the access range and throw a IndexOutOfBoundsException if exceeded.
    
    Parameters:
    
    buffer - to be checked.
    
    index - at which the access will begin.
    
    length - of the range accessed.
  - address
```
public static long address(ByteBuffer buffer)
```
    Get the address at which the underlying buffer storage begins.
    
    Parameters:
    
    buffer - that wraps the underlying storage.
    
    Returns:
    
    the memory address at which the buffer storage begins.
  - array
```
public static byte[] array(ByteBuffer buffer)
```
    Get the array from a read-only ByteBuffer similar to ByteBuffer.array().
    
    Parameters:
    
    buffer - that wraps the underlying array.
    
    Returns:
    
    the underlying array.
  - arrayOffset
```
public static int arrayOffset(ByteBuffer buffer)
```
    Get the array offset from a read-only ByteBuffer similar to ByteBuffer.arrayOffset().
    
    Parameters:
    
    buffer - that wraps the underlying array.
    
    Returns:
    
    the underlying array offset at which this ByteBuffer starts.
  - allocateDirectAligned
```
public static ByteBuffer allocateDirectAligned(int capacity,
                                               int alignment)
```
    Allocate a new direct ByteBuffer that is aligned on a given alignment boundary.
    
    Parameters:
    
    capacity - required for the buffer.
    
    alignment - boundary at which the buffer should begin.
    
    Returns:
    
    a new ByteBuffer with the required alignment.
    
    Throws:
    
    IllegalArgumentException - if the alignment is not a power of 2.
  - free
```
public static void free(DirectBuffer buffer)
```
    Free the underlying direct ByteBuffer by invoking Cleaner on it. No op if null or if the underlying ByteBuffer non-direct.
    
    Parameters:
    
    buffer - to be freed
    
    See Also:
    
    ByteBuffer.isDirect()
  - free
```
public static void free(ByteBuffer buffer)
```
    Free direct ByteBuffer by invoking Cleaner on it. No op if null or non-direct ByteBuffer.
    
    Parameters:
    
    buffer - to be freed
    
    See Also:
    
    ByteBuffer.isDirect()

Class BufferUtil

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

NULL_BYTES

NATIVE_BYTE_ORDER

ARRAY_BASE_OFFSET

BYTE_BUFFER_HB_FIELD_OFFSET

BYTE_BUFFER_OFFSET_FIELD_OFFSET

BYTE_BUFFER_ADDRESS_FIELD_OFFSET

Method Detail

boundsCheck

boundsCheck

address

array

arrayOffset

allocateDirectAligned

free

free