org.rrd4j.core.RrdNioBackend

All Implemented Interfaces:: RrdFileBackend

public class RrdNioBackend
extends ByteBufferBackend
implements RrdFileBackend

Backend which is used to store RRD data to ordinary disk files using java.nio.* package. This is the default backend engine.

Field Summary

Fields inherited from class org.rrd4j.core.RrdBackend
BYTEORDER

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`RrdNioBackend(String path, boolean readOnly, RrdSyncThreadPool threadPool, int syncPeriod)`	Creates RrdFileBackend object for the given file path, backed by java.nio.* classes.

Method Summary

Modifier and Type	Method	Description
`void`	`close()`	Closes the underlying RRD file.
`String`	`getCanonicalPath()`	Returns canonical path to the file on the disk.
`long`	`getLength()`	Returns the number of RRD bytes in the underlying storage.
`protected void`	`setLength(long newLength)`	Sets the number of bytes in the underlying RRD storage.
`protected void`	`sync()`	This method forces all data cached in memory but not yet stored in the file, to be stored in it.

Methods inherited from class org.rrd4j.core.ByteBufferBackend

getCharBuffer, isDirty, read, readDouble, readDouble, readInt, readLong, readShort, rrdClose, setByteBuffer, write, writeDouble, writeDouble, writeDouble, writeInt, writeLong, writeShort, writeString

Methods inherited from class org.rrd4j.core.RrdBackend

done, getFactory, getPath, getUri, isCachingAllowed, isInstanceCreated, readAll, readString, writeString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details
- RrdNioBackend
  
  protected RrdNioBackend(String path, boolean readOnly, RrdSyncThreadPool threadPool, int syncPeriod) throws IOException
  
  Creates RrdFileBackend object for the given file path, backed by java.nio.* classes.
  
  Parameters:
  
  path - Path to a file
  
  readOnly - True, if file should be open in a read-only mode. False otherwise
  
  syncPeriod - See RrdNioBackendFactory.setSyncPeriod(int) for explanation
  
  threadPool - a RrdSyncThreadPool object, it can be null.
  
  Throws:
  
  IOException - Thrown in case of I/O error
Method Details
- setLength
  
  protected void setLength(long newLength) throws IOException
  
  Sets the number of bytes in the underlying RRD storage. This method is called only once, immediately after a new RRD storage gets created. Sets length of the underlying RRD file. This method is called only once, immediately after a new RRD file gets created.
  
  Specified by:
  
  setLength in class RrdBackend
  
  Parameters:
  
  newLength - Length of the underlying RRD storage in bytes.
  
  Throws:
  
  IllegalArgumentException - if the length is bigger that the possible mapping position (2GiB).
  
  IOException - Thrown in case of I/O error.
- close
  
  public void close() throws IOException
  
  Closes the underlying RRD file.
  
  Overrides:
  
  close in class ByteBufferBackend
  
  Throws:
  
  IOException - Thrown in case of I/O error.
- sync
  
  protected void sync()
  
  This method forces all data cached in memory but not yet stored in the file, to be stored in it.
- getLength
  
  public long getLength() throws IOException
  
  Description copied from class: RrdBackend
  
  Returns the number of RRD bytes in the underlying storage.
  
  Specified by:
  
  getLength in class RrdBackend
  
  Returns:
  
  Number of RRD bytes in the storage.
  
  Throws:
  
  IOException - Thrown in case of I/O error.
- getCanonicalPath
  
  public String getCanonicalPath() throws IOException
  
  Description copied from interface: RrdFileBackend
  
  Returns canonical path to the file on the disk.
  
  Specified by:
  
  getCanonicalPath in interface RrdFileBackend
  
  Returns:
  
  Canonical file path
  
  Throws:
  
  IOException - Thrown in case of I/O error

Class RrdNioBackend

Field Summary

Fields inherited from class org.rrd4j.core.RrdBackend

Constructor Summary

Method Summary

Methods inherited from class org.rrd4j.core.ByteBufferBackend

Methods inherited from class org.rrd4j.core.RrdBackend

Methods inherited from class java.lang.Object

Constructor Details

RrdNioBackend

Method Details

setLength

close

sync

getLength

getCanonicalPath