Package com.sleepycat.db

Class CacheFile

java.lang.Object
com.sleepycat.db.CacheFile
public class CacheFile extends Object
This class allows applications to modify settings for a Database using the Database.getCacheFile.

  • Method Summary

    Modifier and Type
    Method
    Description
    long
    getMaximumSize()
    Return the maximum size for the file backing the database, or 0 if no maximum file size has been configured.
    boolean
    getNoFile()
    Return true if the opening of backing temporary files for in-memory databases has been disallowed.
    CacheFilePriority
    getPriority()
    Return the cache priority for pages from the specified file.
    boolean
    getUnlink()
    Return true if the file will be removed when the last reference to it is closed.
    void
    setMaximumSize(long bytes)
    Set the maximum size for the file backing the database.
    void
    setNoFile(boolean onoff)
    Disallow opening backing temporary files for in-memory databases, even if they expand to fill the entire cache.
    void
    setPriority(CacheFilePriority priority)
    Set the cache priority for pages from the specified file.
    void
    setUnlink(boolean onoff)
    Remove the file when the last reference to it is closed.

    Methods inherited from class java.lang.Object

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

  • Method Details

    • getPriority

      public CacheFilePriority getPriority() throws DatabaseException
      Return the cache priority for pages from the specified file.

      This method may be called at any time during the life of the application.

      Returns:
      The cache priority for pages from the specified file.

      Throws:
      DatabaseException - if a failure occurs.

    • setPriority

      public void setPriority(CacheFilePriority priority) throws DatabaseException
      Set the cache priority for pages from the specified file.

      The priority of a page biases the replacement algorithm to be more or less likely to discard a page when space is needed in the buffer pool. The bias is temporary, and pages will eventually be discarded if they are not referenced again. Setting the priority is only advisory, and does not guarantee pages will be treated in a specific way.

      This method may be called at any time during the life of the application.

      Parameters:
      priority - The cache priority for pages from the specified file.

      Throws:
      DatabaseException - if a failure occurs.

    • getMaximumSize

      public long getMaximumSize() throws DatabaseException
      Return the maximum size for the file backing the database, or 0 if no maximum file size has been configured.

      This method may be called at any time during the life of the application.

      Returns:
      The maximum size for the file backing the database, or 0 if no maximum file size has been configured.

      Throws:
      DatabaseException - if a failure occurs.

    • setMaximumSize

      public void setMaximumSize(long bytes) throws DatabaseException
      Set the maximum size for the file backing the database.

      Attempts to allocate new pages in the file after the limit has been reached will fail.

      This method may be called at any time during the life of the application.

      Parameters:
      bytes - The maximum size for the file backing the database.

      Throws:
      DatabaseException - if a failure occurs.

    • getNoFile

      public boolean getNoFile() throws DatabaseException
      Return true if the opening of backing temporary files for in-memory databases has been disallowed.

      This method may be called at any time during the life of the application.

      Returns:
      True if the opening of backing temporary files for in-memory databases has been disallowed.

      Throws:
      DatabaseException - if a failure occurs.

    • setNoFile

      public void setNoFile(boolean onoff) throws DatabaseException
      Disallow opening backing temporary files for in-memory databases, even if they expand to fill the entire cache.

      Attempts to create new file pages after the cache has been filled will fail.

      This method may be called at any time during the life of the application.

      Parameters:
      onoff - If true, disallow opening backing temporary files for in-memory databases, even if they expand to fill the entire cache.

      Throws:
      DatabaseException - if a failure occurs.

    • getUnlink

      public boolean getUnlink() throws DatabaseException
      Return true if the file will be removed when the last reference to it is closed.

      This method may be called at any time during the life of the application.

      Returns:
      True if the file will be removed when the last reference to it is closed.

      Throws:
      DatabaseException - if a failure occurs.

    • setUnlink

      public void setUnlink(boolean onoff) throws DatabaseException
      Remove the file when the last reference to it is closed.

      This method may be called at any time during the life of the application.

      Parameters:
      onoff - If true, remove the file when the last reference to it is closed.

      Throws:
      DatabaseException - if a failure occurs.