ReedSolomon (ktucp-fec 1.1 API)

java.lang.Object
- com.hjcenry.fec.ReedSolomon

```
public class ReedSolomon
extends Object
```
Reed-Solomon Coding over 8-bit values.

字段概要

字段
限定符和类型	字段和说明
`private CodingLoop`	`codingLoop`
`private int`	`dataShardCount`
`private static ByteBufCodingLoop`	`LOOP`
`private Matrix`	`matrix`
`private byte[][]`	`parityRows` Rows from the matrix for encoding parity, each one as its own byte array to allow for efficient access while encoding.
`private int`	`parityShardCount`
`private int`	`totalShardCount`

构造器概要

构造器
构造器和说明
`ReedSolomon(int dataShardCount, int parityShardCount, CodingLoop codingLoop)` Initializes a new encoder/decoder, with a chosen coding loop.

方法概要

所有方法静态方法实例方法具体方法
限定符和类型	方法和说明
`private static Matrix`	`buildMatrix(int dataShards, int totalShards)` Create the matrix to use for encoding, given the number of data shards and the number of total shards.
`private void`	`checkBuffersAndSizes(byte[][] shards, int offset, int byteCount)` Checks the consistency of arguments passed to public methods.
`private void`	`checkBuffersAndSizes(io.netty.buffer.ByteBuf[] shards, int offset, int byteCount)` Checks the consistency of arguments passed to public methods.
`static ReedSolomon`	`create(int dataShardCount, int parityShardCount)` Creates a ReedSolomon codec with the default coding loop.
`void`	`decodeMissing(byte[][] shards, boolean[] shardPresent, int offset, int byteCount)` Given a list of shards, some of which contain data, fills in the ones that don't have data.
`void`	`decodeMissing(io.netty.buffer.ByteBuf[] shards, boolean[] shardPresent, int offset, int byteCount)`
`void`	`encodeParity(byte[][] shards, int offset, int byteCount)` Encodes parity for a set of data shards.
`void`	`encodeParity(io.netty.buffer.ByteBuf[] shards, int offset, int byteCount)`
`int`	`getDataShardCount()` Returns the number of data shards.
`int`	`getParityShardCount()` Returns the number of parity shards.
`int`	`getTotalShardCount()` Returns the total number of shards.
`boolean`	`isParityCorrect(byte[][] shards, int firstByte, int byteCount)` Returns true if the parity shards contain the right data.
`boolean`	`isParityCorrect(byte[][] shards, int firstByte, int byteCount, byte[] tempBuffer)` Returns true if the parity shards contain the right data.
`private static Matrix`	`vandermonde(int rows, int cols)` Create a Vandermonde matrix, which is guaranteed to have the property that any subset of rows that forms a square matrix is invertible.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 字段详细资料
  - dataShardCount
```
private final int dataShardCount
```
  - parityShardCount
```
private final int parityShardCount
```
  - totalShardCount
```
private final int totalShardCount
```
  - matrix
```
private final Matrix matrix
```
  - codingLoop
```
private final CodingLoop codingLoop
```
  - parityRows
```
private final byte[][] parityRows
```
    Rows from the matrix for encoding parity, each one as its own byte array to allow for efficient access while encoding.
  - LOOP
```
private static final ByteBufCodingLoop LOOP
```
- 构造器详细资料
  - ReedSolomon
```
public ReedSolomon(int dataShardCount,
                   int parityShardCount,
                   CodingLoop codingLoop)
```
    Initializes a new encoder/decoder, with a chosen coding loop.
- 方法详细资料
  - create
```
public static ReedSolomon create(int dataShardCount,
                                 int parityShardCount)
```
    Creates a ReedSolomon codec with the default coding loop.
  - getDataShardCount
```
public int getDataShardCount()
```
    Returns the number of data shards.
  - getParityShardCount
```
public int getParityShardCount()
```
    Returns the number of parity shards.
  - getTotalShardCount
```
public int getTotalShardCount()
```
    Returns the total number of shards.
  - encodeParity
```
public void encodeParity(byte[][] shards,
                         int offset,
                         int byteCount)
```
    Encodes parity for a set of data shards.
    
    参数:
    
    shards - An array containing data shards followed by parity shards. Each shard is a byte array, and they must all be the same size.
    
    offset - The index of the first byte in each shard to encode.
    
    byteCount - The number of bytes to encode in each shard.
  - encodeParity
```
public void encodeParity(io.netty.buffer.ByteBuf[] shards,
                         int offset,
                         int byteCount)
```
  - isParityCorrect
```
public boolean isParityCorrect(byte[][] shards,
                               int firstByte,
                               int byteCount)
```
    Returns true if the parity shards contain the right data.
    
    参数:
    
    shards - An array containing data shards followed by parity shards. Each shard is a byte array, and they must all be the same size.
    
    firstByte - The index of the first byte in each shard to check.
    
    byteCount - The number of bytes to check in each shard.
  - isParityCorrect
```
public boolean isParityCorrect(byte[][] shards,
                               int firstByte,
                               int byteCount,
                               byte[] tempBuffer)
```
    Returns true if the parity shards contain the right data. This method may be significantly faster than the one above that does not use a temporary buffer.
    
    参数:
    
    shards - An array containing data shards followed by parity shards. Each shard is a byte array, and they must all be the same size.
    
    firstByte - The index of the first byte in each shard to check.
    
    byteCount - The number of bytes to check in each shard.
    
    tempBuffer - A temporary buffer (the same size as each of the shards) to use when computing parity.
  - decodeMissing
```
public void decodeMissing(byte[][] shards,
                          boolean[] shardPresent,
                          int offset,
                          int byteCount)
```
    Given a list of shards, some of which contain data, fills in the ones that don't have data. Quickly does nothing if all of the shards are present. If any shards are missing (based on the flags in shardsPresent), the data in those shards is recomputed and filled in.
  - decodeMissing
```
public void decodeMissing(io.netty.buffer.ByteBuf[] shards,
                          boolean[] shardPresent,
                          int offset,
                          int byteCount)
```
  - checkBuffersAndSizes
```
private void checkBuffersAndSizes(io.netty.buffer.ByteBuf[] shards,
                                  int offset,
                                  int byteCount)
```
    Checks the consistency of arguments passed to public methods.
  - checkBuffersAndSizes
```
private void checkBuffersAndSizes(byte[][] shards,
                                  int offset,
                                  int byteCount)
```
    Checks the consistency of arguments passed to public methods.
  - buildMatrix
```
private static Matrix buildMatrix(int dataShards,
                                  int totalShards)
```
    Create the matrix to use for encoding, given the number of data shards and the number of total shards. The top square of the matrix is guaranteed to be an identity matrix, which means that the data shards are unchanged after encoding.
  - vandermonde
```
private static Matrix vandermonde(int rows,
                                  int cols)
```
    Create a Vandermonde matrix, which is guaranteed to have the property that any subset of rows that forms a square matrix is invertible.
    
    参数:
    
    rows - Number of rows in the result.
    
    cols - Number of columns in the result.
    
    返回:
    
    A Matrix.

类 ReedSolomon

字段概要

构造器概要

方法概要

从类继承的方法 java.lang.Object

字段详细资料

dataShardCount

parityShardCount

totalShardCount

matrix

codingLoop

parityRows

LOOP

构造器详细资料

ReedSolomon

方法详细资料

create

getDataShardCount

getParityShardCount

getTotalShardCount

encodeParity

encodeParity

isParityCorrect

isParityCorrect

decodeMissing

decodeMissing

checkBuffersAndSizes

checkBuffersAndSizes

buildMatrix

vandermonde