Module org.eclipse.jgit
Package org.eclipse.jgit.internal.storage.dfs

Interface DfsBlockCacheTable

public interface DfsBlockCacheTable
Block cache table.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static interface 
    DfsBlockCacheTable.BlockCacheStats
    Provides methods used with Block Cache statistics.

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    contains(DfsStreamKey key, long position)
    Check if the block cache contains an object identified by (key, position).
    <T> T
    get(DfsStreamKey key, long position)
    Get the object identified by (key, position) from the block cache.
    List<DfsBlockCacheTable.BlockCacheStats>
    getBlockCacheStats()
    Get the list of DfsBlockCacheTable.BlockCacheStats held by this cache.
    String
    getName()
    Get the name of the table.
    org.eclipse.jgit.internal.storage.dfs.DfsBlock
    getOrLoad(org.eclipse.jgit.internal.storage.dfs.BlockBasedFile file, long position, DfsReader dfsReader, org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.ReadableChannelSupplier fileChannel)
    Look up a cached object, creating and loading it if it doesn't exist.
    <T> org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.Ref<T>
    getOrLoadRef(DfsStreamKey key, long position, org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.RefLoader<T> loader)
    Look up a cached object, creating and loading it if it doesn't exist.
    boolean
    hasBlock0(DfsStreamKey key)
    Quickly check if the cache contains block 0 of the given stream.
    void
    put(org.eclipse.jgit.internal.storage.dfs.DfsBlock v)
    Put a block in the block cache.
    <T> org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.Ref<T>
    put(DfsStreamKey key, long pos, long size, T v)
    Put a block in the block cache.
    <T> org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.Ref<T>
    putRef(DfsStreamKey key, long size, T v)
    Put an object in the block cache.

  • Method Details

    • hasBlock0

      boolean hasBlock0(DfsStreamKey key)
      Quickly check if the cache contains block 0 of the given stream.

      This can be useful for sophisticated pre-read algorithms to quickly determine if a file is likely already in cache, especially small reftables which may be smaller than a typical DFS block size.

      Parameters:
      key - the file to check.
      Returns:
      true if block 0 (the first block) is in the cache.

    • getOrLoad

      org.eclipse.jgit.internal.storage.dfs.DfsBlock getOrLoad(org.eclipse.jgit.internal.storage.dfs.BlockBasedFile file, long position, DfsReader dfsReader, org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.ReadableChannelSupplier fileChannel) throws IOException
      Look up a cached object, creating and loading it if it doesn't exist.
      Parameters:
      file - the pack that "contains" the cached object.
      position - offset within pack of the object.
      dfsReader - current thread's reader.
      fileChannel - supplier for channel to read pack.
      Returns:
      the object reference.
      Throws:
      IOException - the reference was not in the cache and could not be loaded.

    • getOrLoadRef

      <T> org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.Ref<T> getOrLoadRef(DfsStreamKey key, long position, org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.RefLoader<T> loader) throws IOException
      Look up a cached object, creating and loading it if it doesn't exist.
      Parameters:
      key - the stream key of the pack.
      position - the position in the key. The default should be 0.
      loader - the function to load the reference.
      Returns:
      the object reference.
      Throws:
      IOException - the reference was not in the cache and could not be loaded.

    • put

      void put(org.eclipse.jgit.internal.storage.dfs.DfsBlock v)
      Put a block in the block cache.
      Parameters:
      v - the block to put in the cache.

    • put

      <T> org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.Ref<T> put(DfsStreamKey key, long pos, long size, T v)
      Put a block in the block cache.
      Parameters:
      key - the stream key of the pack.
      pos - the position in the key.
      size - the size of the object.
      v - the object to put in the block cache.
      Returns:
      the object reference.

    • putRef

      <T> org.eclipse.jgit.internal.storage.dfs.DfsBlockCache.Ref<T> putRef(DfsStreamKey key, long size, T v)
      Put an object in the block cache.
      Parameters:
      key - the stream key of the pack.
      size - the size of the object.
      v - the object to put in the block cache.
      Returns:
      the object reference.

    • contains

      boolean contains(DfsStreamKey key, long position)
      Check if the block cache contains an object identified by (key, position).
      Parameters:
      key - the stream key of the pack.
      position - the position in the key.
      Returns:
      if the block cache contains the object identified by (key, position).

    • get

      <T> T get(DfsStreamKey key, long position)
      Get the object identified by (key, position) from the block cache.
      Parameters:
      key - the stream key of the pack.
      position - the position in the key.
      Returns:
      the object identified by (key, position).

    • getBlockCacheStats

      List<DfsBlockCacheTable.BlockCacheStats> getBlockCacheStats()
      Get the list of DfsBlockCacheTable.BlockCacheStats held by this cache.

      The returned list has a DfsBlockCacheTable.BlockCacheStats per configured cache table, with a minimum of 1 DfsBlockCacheTable.BlockCacheStats object returned. Use AggregatedBlockCacheStats to combine the results of the stats in the list for an aggregated view of the cache's stats.

      Returns:
      the list of DfsBlockCacheTable.BlockCacheStats held by this cache.

    • getName

      String getName()
      Get the name of the table.
      Returns:
      this table's name.