Package org.rrd4j.core

Class RrdRandomAccessFileBackend

java.lang.Object
org.rrd4j.core.RrdBackend
org.rrd4j.core.RrdRandomAccessFileBackend
All Implemented Interfaces:
RrdFileBackend
Direct Known Subclasses:
RrdSafeFileBackend
public class RrdRandomAccessFileBackend
extends RrdBackend
implements RrdFileBackend
Backend which is used to store RRD data to ordinary files on the disk. This was the default factory before 1.4.0 version. This backend is based on the RandomAccessFile class (java.io.* package).

  • Field Details

  • Constructor Details

    • RrdRandomAccessFileBackend

      protected RrdRandomAccessFileBackend​(String path, boolean readOnly) throws IOException
      Creates RrdFileBackend object for the given file path, backed by RandomAccessFile object.
      Parameters:
      path - Path to a file
      readOnly - True, if file should be open in a read-only mode. False otherwise
      Throws:
      IOException - Thrown in case of I/O error

  • Method Details

    • close

      protected void close() throws IOException
      Closes the underlying RRD file.
      Specified by:
      close in class RrdBackend
      Throws:
      IOException - Thrown in case of I/O error

    • write

      protected void write​(long offset, byte[] b) throws IOException
      Writes bytes to the underlying RRD file on the disk
      Specified by:
      write in class RrdBackend
      Parameters:
      offset - Starting file offset
      b - Bytes to be written.
      Throws:
      IOException - Thrown in case of I/O error

    • read

      public void read​(long offset, byte[] b) throws IOException
      Reads a number of bytes from the RRD file on the disk
      Specified by:
      read in class RrdBackend
      Parameters:
      offset - Starting file offset
      b - Buffer which receives bytes read from the file.
      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

    • getLength

      public long getLength() throws IOException
      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.

    • setLength

      protected void setLength​(long length) 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:
      length - Length of the underlying RRD storage in bytes.
      Throws:
      IOException - Thrown in case of I/O error.