コンストラクタの詳細

• RrdNioBackend

  protected RrdNioBackend​(java.lang.String path,
                          boolean readOnly,
                          int syncPeriod)
                   throws java.io.IOException

  Creates RrdFileBackend object for the given file path, backed by java.nio.* classes. This constructor will create a SyncManager for each instance, which is very inefficient. It is recommended that you instead use the RrdNioBackend(String, boolean, SyncManager) constructor instead.

  パラメータ:

  path - Path to a JRB file.

  readOnly - True, if file should be open in a read-only mode. False otherwise

  syncPeriod - How often (in seconds) to sync MMAP'd RRD data to disk

  例外:

  java.io.IOException - Thrown in case of I/O error

• RrdNioBackend

  protected RrdNioBackend​(java.lang.String path,
                          boolean readOnly,
                          SyncManager syncManager)
                   throws java.io.IOException

  Creates RrdFileBackend object for the given file path, backed by java.nio.* classes.

  パラメータ:

  path - Path to a file

  readOnly - True, if file should be open in a read-only mode. False otherwise.

  syncManager - An object for managing synchronization of NIO-backed RRDs, generally owned by the backend factory. If null, MMAP'd data will only be synchronized to disk upon unmap. Note that if the file is opened read-only, the SyncManager is ignored. unmapFile()

  例外:

  java.io.IOException - Thrown in case of I/O error

メソッドの詳細

• finalize

  protected void finalize​()
                   throws java.lang.Throwable

  オーバーライド:

  finalize クラス内 java.lang.Object

  例外:

  java.lang.Throwable

• setLength

  protected void setLength​(long newLength)
                    throws java.io.IOException

  Sets length of the underlying RRD file. This method is called only once, immediately after a new RRD file gets created.

  オーバーライド:

  setLength クラス内 RrdFileBackend

  パラメータ:

  newLength - Length of the RRD file

  例外:

  java.io.IOException - Thrown in case of I/O error.

• write

  protected void write​(long offset,
                       byte[] b)
                throws java.io.IOException

  Writes bytes to the underlying RRD file on the disk

  オーバーライド:

  write クラス内 RrdFileBackend

  パラメータ:

  offset - Starting file offset

  b - Bytes to be written.

  例外:

  java.io.IOException - Thrown in case of I/O error

• read

  protected void read​(long offset,
                      byte[] b)
               throws java.io.IOException

  Reads a number of bytes from the RRD file on the disk

  オーバーライド:

  read クラス内 RrdFileBackend

  パラメータ:

  offset - Starting file offset

  b - Buffer which receives bytes read from the file.

  例外:

  java.io.IOException - Thrown in case of I/O error.

• close

  public void close​()
             throws java.io.IOException

  Closes the underlying RRD file.

  オーバーライド:

  close クラス内 RrdFileBackend

  例外:

  java.io.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.