ByteArray

java.lang.Object
- org.epics.archiverappliance.ByteArray

```
public class ByteArray
extends Object
```
A version of byte[] that is used to provide some optimization for data retrieval and the like. This is very similar to NIO's ByteBuffer but has all its internal's exposed and is meant to pass a byte[]+offset+length around within the appliance archiver. Many event streams reuse the same ByteArray across events in order to minimize memory allocation costs. And as we reuse ByteArray instances so we have a reset method. The convention for ByteArrays within Events is that they stored the escaped bytes (@see LineEscaper) and the inPlaceUnescape method is used to unescape these bytes. For example, in summary, the PB code will ByteArray bar = new ByteArray(); LineByteStream lbs = new LineByteStream(path...); lbs.readLine(bar); while(!bar.isEmpty()) { SomeType.newBuilder().mergeFrom(bar.inPlaceUnescape().unescapedData, bar.off, bar.unescapedLen).build(); lbs.readLine(bar); } The readLine logic in lbs has the code necessary to increase the length of the data field as required. Because many event streams reuse the same ByteArray across events, life becomes interesting as we need to remember to use makeClone anytime we want to span the Event across the iterator that generated it. Spoke with Luofeng about this and we both came to the conclusion that we should try to make this work as much as possible as the GC gains itself are quite a bit.

Author:

mshankar

Field Summary

Fields
Modifier and Type Field Description

byte[] data

int len

int off

byte[] unescapedData

int unescapedLen

Constructor Summary

Constructors
Constructor Description

ByteArray(byte[] src)

ByteArray(int size)

Method Summary

Modifier and Type	Method	Description
`void`	`doubleBufferSize()`	Increases the size of the array to twice what it is currently subject to a maximum
`ByteArray`	`inPlaceUnescape()`
`boolean`	`isEmpty()`
`void`	`reset()`
`byte[]`	`toBytes()`	Use this for unit tests and the like...
`byte[]`	`unescapedBytes()`

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

Field Detail

data
```
public byte[] data
```

off
```
public int off
```

len
```
public int len
```

unescapedData
```
public byte[] unescapedData
```

unescapedLen
```
public int unescapedLen
```

Constructor Detail

ByteArray
```
public ByteArray(int size)
```

ByteArray
```
public ByteArray(byte[] src)
```

Method Detail
- reset
```
public void reset()
```
- toBytes
```
public byte[] toBytes()
```
  Use this for unit tests and the like...
  
  Returns:
  
  See Also:
  
  System.arraycopy
- unescapedBytes
```
public byte[] unescapedBytes()
```
- doubleBufferSize
```
public void doubleBufferSize()
                      throws LineTooLongException
```
  Increases the size of the array to twice what it is currently subject to a maximum
  
  Throws:
  
  LineTooLongException -
- isEmpty
```
public boolean isEmpty()
```
- inPlaceUnescape
```
public ByteArray inPlaceUnescape()
```