loci.common

Interface IRandomAccess

All Superinterfaces:

DataInput, DataOutput

All Known Implementing Classes:

AbstractNIOHandle, ByteArrayHandle, BZip2Handle, FileHandle, GZipHandle, NIOFileHandle, S3Handle, StreamHandle, URLHandle, ZipHandle

public interface IRandomAccess
extends DataInput, DataOutput

Interface for random access into structures (e.g., files or arrays).

Author:

Curtis Rueden ctrueden at wisc.edu

Method Summary

Modifier and Type	Method and Description
void	close() Closes this random access stream and releases any system resources associated with the stream.
boolean	exists() Returns whether this refers to a valid object
long	getFilePointer() Returns the current offset in this stream.
ByteOrder	getOrder() Returns the current order (endianness) of the stream.
long	length() Returns the length of this stream.
int	read(byte[] b) Reads up to b.length bytes of data from this stream into an array of bytes.
int	read(byte[] b, int off, int len) Reads up to len bytes of data from this stream into an array of bytes.
int	read(ByteBuffer buffer) Reads up to buffer.capacity() bytes of data from this stream into a ByteBuffer.
int	read(ByteBuffer buffer, int offset, int len) Reads up to len bytes of data from this stream into a ByteBuffer.
void	seek(long pos) Sets the stream pointer offset, measured from the beginning of this stream, at which the next read or write occurs.
void	setOrder(ByteOrder order) Sets the byte order (endianness) of the stream.
long	skipBytes(long n) A long variant of DataInput.skipBytes(int).
void	write(ByteBuffer buf) Writes up to buffer.capacity() bytes of data from the given ByteBuffer to this stream.
void	write(ByteBuffer buf, int off, int len) Writes up to len bytes of data from the given ByteBuffer to this stream.

Methods inherited from interface java.io.DataInput

readBoolean, readByte, readChar, readDouble, readFloat, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedShort, readUTF, skipBytes

Methods inherited from interface java.io.DataOutput

write, write, write, writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeDouble, writeFloat, writeInt, writeLong, writeShort, writeUTF

Method Detail

close

void close()
    throws IOException

Closes this random access stream and releases any system resources associated with the stream.

Throws:

IOException - if the underlying stream(s) could not be closed

getFilePointer

long getFilePointer()
             throws IOException

Returns the current offset in this stream.

Returns:

the current byte offset within the file; expected to be non-negative and less than the value of #length()

Throws:

IOException - if the offset cannot be retrieved

exists

boolean exists()
        throws IOException

Returns whether this refers to a valid object

Returns:

true if this refers to a valid object

Throws:

IOException - if unable to determine whether the object is valid

length

long length()
     throws IOException

Returns the length of this stream.

Returns:

the length in bytes of the stream

Throws:

IOException - if the length cannot be retrieved

getOrder

ByteOrder getOrder()

Returns the current order (endianness) of the stream.

Returns:

See above.

setOrder

void setOrder(ByteOrder order)

Sets the byte order (endianness) of the stream.

Parameters:

order - Order to set.

read

int read(byte[] b)
  throws IOException

Reads up to b.length bytes of data from this stream into an array of bytes.

Parameters:

b - the array to fill from this stream

Returns:

the total number of bytes read into the buffer.

Throws:

IOException - if reading is not possible

read

int read(byte[] b,
         int off,
         int len)
  throws IOException

Reads up to len bytes of data from this stream into an array of bytes.

Parameters:

b - the array to fill from this stream

off - the offset in b from which to start filling; expected to be non-negative and no greater than b.length - len

len - the number of bytes to read; expected to be positive and no greater than b.length - offset

Returns:

the total number of bytes read into the buffer.

Throws:

IOException - if reading is not possible

read

int read(ByteBuffer buffer)
  throws IOException

Reads up to buffer.capacity() bytes of data from this stream into a ByteBuffer.

Parameters:

buffer - the ByteBuffer to fill from this stream

Returns:

the total number of bytes read into the buffer.

Throws:

IOException - if reading is not possible

read

int read(ByteBuffer buffer,
         int offset,
         int len)
  throws IOException

Reads up to len bytes of data from this stream into a ByteBuffer.

Parameters:

buffer - the ByteBuffer to fill from this stream

offset - the offset in b from which to start filling; expected to be non-negative and no greater than buffer.capacity() - len

len - the number of bytes to read; expected to be positive and no greater than buffer.capacity() - offset

Returns:

the total number of bytes read into the buffer.

Throws:

IOException - if reading is not possible

seek

void seek(long pos)
   throws IOException

Sets the stream pointer offset, measured from the beginning of this stream, at which the next read or write occurs.

Parameters:

pos - new byte offset (pointer) in the current stream. Unless otherwise noted, may be larger or smaller than the current pointer, but must be non-negative and less than the value of #length()

Throws:

IOException - if pos is invalid or the seek fails

See Also:

getFilePointer()

skipBytes

long skipBytes(long n)
        throws IOException

A long variant of DataInput.skipBytes(int).

Parameters:

n - the number of bytes to skip

Returns:

the number of bytes skipped

Throws:

IOException - if the operation failed

write

void write(ByteBuffer buf)
    throws IOException

Writes up to buffer.capacity() bytes of data from the given ByteBuffer to this stream.

Parameters:

buf - the ByteBuffer containing bytes to write to this stream

Throws:

IOException - if writing is not possible

write

void write(ByteBuffer buf,
           int off,
           int len)
    throws IOException

Writes up to len bytes of data from the given ByteBuffer to this stream.

Parameters:

buf - the ByteBuffer containing bytes to write to this stream

off - the offset in b from which to start writing; expected to be non-negative and no greater than buf.capacity() - len

len - the number of bytes to write; expected to be positive and no greater than buf.capacity() - offset

Throws:

IOException - if writing is not possible