/// <summary>
/// 从文件打开B+树
/// </summary>
/// <param name="treeFileStream">指定树文件的文件流</param>
/// <param name="blockFileStream">指定块文件的文件流</param>
/// <returns>B+树</returns>
public static BPlusTreeBytes Open(Stream treeFileStream, Stream blockFileStream)
{
BPlusTreeLong tree = BPlusTreeLong.SetupFromExistingStream(treeFileStream, (long)0);
LinkedFile archive = LinkedFile.SetupFromExistingStream(blockFileStream, (long)0);
return(new BPlusTreeBytes(tree, archive));
}
/// <summary>
/// 创建B+树
/// </summary>
/// <param name="treeFileStream">指定树文件的文件流</param>
/// <param name="blockFileStream">指定块文件的文件流</param>
/// <param name="keyLength">树允许的键的长度</param>
/// <param name="nodeCapacity">树允许的各子节点的最大容量</param>
/// <param name="blockSize">块大小</param>
/// <returns>B+树</returns>
public static BPlusTreeBytes Create(Stream treeFileStream, Stream blockFileStream, int keyLength, int nodeCapacity, int blockSize)
{
BPlusTreeLong tree = BPlusTreeLong.InitializeInStream(treeFileStream, (long)0, keyLength, nodeCapacity);
LinkedFile archive = LinkedFile.InitializeInStream(blockFileStream, (long)0, blockSize);
return(new BPlusTreeBytes(tree, archive));
}
/// <summary>
/// 从指定的流初始化链式块文件
/// </summary>
/// <param name="fromFile">指定的流</param>
/// <param name="seekStart">流起始索引点</param>
/// <returns>链式块文件</returns>
public static LinkedFile SetupFromExistingStream(Stream fromFile, long seekStart)
{
LinkedFile file = new LinkedFile(fromFile, seekStart, StoredConstants.LinkedFileHeaderPrefix, 100); // dummy block size for now
file.ReadFileHeader();
file.BlockFile = BlockFile.SetupFromExistingStream(fromFile, seekStart + file.FileHeaderSize, StoredConstants.BlockFileHeaderPrefix);
return(file);
}
/// <summary>
/// 从指定的流初始化链式块文件
/// </summary>
/// <param name="fromFile">指定的流</param>
/// <param name="seekStart">流起始索引点</param>
/// <param name="blockSize">块的大小</param>
/// <returns>链式块文件</returns>
public static LinkedFile InitializeInStream(Stream fromFile, long seekStart, int blockSize)
{
LinkedFile file = new LinkedFile(fromFile, seekStart, StoredConstants.LinkedFileHeaderPrefix, blockSize);
file.WriteFileHeader();
file.BlockFile = BlockFile.InitializeInStream(fromFile, seekStart + file.FileHeaderSize, StoredConstants.BlockFileHeaderPrefix, LinkedBlockOverhead + blockSize);
return(file);
}
/// <summary>
/// 从指定的流初始化链式块文件
/// </summary>
/// <param name="fromFile">指定的流</param>
/// <param name="seekStart">流起始索引点</param>
/// <returns>链式块文件</returns>
public static LinkedFile SetupFromExistingStream(Stream fromFile, long seekStart)
{
LinkedFile file = new LinkedFile(fromFile, seekStart, StoredConstants.LinkedFileHeaderPrefix, 100); // dummy block size for now
file.ReadFileHeader();
file.BlockFile = BlockFile.SetupFromExistingStream(fromFile, seekStart + file.FileHeaderSize, StoredConstants.BlockFileHeaderPrefix);
return file;
}
/// <summary>
/// 从指定的流初始化链式块文件
/// </summary>
/// <param name="fromFile">指定的流</param>
/// <param name="seekStart">流起始索引点</param>
/// <param name="blockSize">块的大小</param>
/// <returns>链式块文件</returns>
public static LinkedFile InitializeInStream(Stream fromFile, long seekStart, int blockSize)
{
LinkedFile file = new LinkedFile(fromFile, seekStart, StoredConstants.LinkedFileHeaderPrefix, blockSize);
file.WriteFileHeader();
file.BlockFile = BlockFile.InitializeInStream(fromFile, seekStart + file.FileHeaderSize, StoredConstants.BlockFileHeaderPrefix, LinkedBlockOverhead + blockSize);
return file;
}
/// <summary>
/// B+树，固定长度字符串为键，映射至Byte数组。
/// </summary>
/// <param name="tree">B+树</param>
/// <param name="archive">链式块文件</param>
internal BPlusTreeBytes(BPlusTreeLong tree, LinkedFile archive)
{
this.tree = tree;
this.archive = archive;
}
/// <summary>
/// B+树，固定长度字符串为键，映射至Byte数组。
/// </summary>
/// <param name="tree">B+树</param>
/// <param name="archive">链式块文件</param>
internal BPlusTreeBytes(BPlusTreeLong tree, LinkedFile archive)
{
this.tree = tree;
this.archive = archive;
}
