Class: Ferret::Store::IndexOutput

Inherits:
Object
  • Object
show all
Defined in:
lib/ferret/store/index_io.rb,
ext/index_io.c

Overview

Ferret’s IO Output methods are defined here. The methods write_byte and write_bytes need to be defined before this class is of any use.

Direct Known Subclasses

BufferedIndexOutput

Instance Method Summary collapse

Instance Method Details

#close ⇒ Object

Closes this stream to further operations.

Raises:

  • (NotImplementedError) 


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# File 'lib/ferret/store/index_io.rb', line 239

def close
  raise NotImplementedError
end

#flush ⇒ Object

Forces any buffered output to be written.

Raises:

  • (NotImplementedError) 


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# File 'lib/ferret/store/index_io.rb', line 234

def flush
  raise NotImplementedError
end

#length ⇒ Object

The number of bytes in the file.

Raises:

  • (NotImplementedError) 


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# File 'lib/ferret/store/index_io.rb', line 255

def length
  raise NotImplementedError
end

#pos ⇒ Object

Returns the current position in this file, where the next write will occur.

Raises:

  • (NotImplementedError) 


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# File 'lib/ferret/store/index_io.rb', line 245

def pos
  raise NotImplementedError
end

#seek(pos) ⇒ Object

Sets current position in this file, where the next write will occur.

Raises:

  • (NotImplementedError) 


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# File 'lib/ferret/store/index_io.rb', line 250

def seek(pos)
  raise NotImplementedError
end

#write_byte(b) ⇒ Object

Writes a single byte.

Raises:

  • (NotImplementedError) 


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# File 'lib/ferret/store/index_io.rb', line 162

def write_byte(b)
  raise NotImplementedError
end

#write_bytes(buf, len) ⇒ Object

Writes an array of bytes.

buf

the bytes to write

len

the number of bytes to write

Raises:

  • (NotImplementedError) 


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# File 'lib/ferret/store/index_io.rb', line 169

def write_bytes(buf, len)
  raise NotImplementedError
end

#write_chars(buf, start, length) ⇒ Object

Writes a sequence of UTF-8 encoded characters from a string.

buf

the source of the characters

start

the first character in the sequence

length

the number of characters in the sequence



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# File 'lib/ferret/store/index_io.rb', line 212

def write_chars(buf, start, length)
  last = start + length
  (start ... last).each do |i|
    write_byte(buf[i])
#          code = buf[i]
#          if code >= 0x01 and code <= 0x7F
#            write_byte(code)
#          else
#            # We need to write unicode characters. ToDo: test that this works.
#            if code > 0x80 and code <= 0x7FF or code == 0
#              write_byte(0xC0 | code >> 6)
#              write_byte(0x80 | code & 0x3F)
#            else
#              write_byte(0xE0 | (code >> 12))
#              write_byte(0x80 | ((code >> 6) & 0x3F))
#              write_byte(0x80 | (code & 0x3F))
#            end
#          end
  end
end

#write_int(i) ⇒ Object Also known as: write_uint

Writes an int as four bytes.



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# File 'lib/ferret/store/index_io.rb', line 174

def write_int(i)
  write_byte((i >> 24) & 0xFF)
  write_byte((i >> 16) & 0xFF)
  write_byte((i >>  8) & 0xFF)
  write_byte(i & 0xFF)
end

#write_long(i) ⇒ Object Also known as: write_ulong

Writes a long as eight bytes.



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# File 'lib/ferret/store/index_io.rb', line 195

def write_long(i)
  write_int(i >> 32)
  write_int(i)
end

#write_string(s) ⇒ Object

Writes a string.



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# File 'lib/ferret/store/index_io.rb', line 202

def write_string(s)
  length = s.length()
  write_vint(length)
  write_chars(s, 0, length)
end

#write_vint(i) ⇒ Object Also known as: write_vlong

Writes an int in a variable-length format. Writes between one and five bytes. Smaller values take fewer bytes. Negative numbers are not supported.



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# File 'lib/ferret/store/index_io.rb', line 185

def write_vint(i)
  while i > 127
    write_byte((i & 0x7f) | 0x80)
    i >>= 7
  end
  write_byte(i)
end