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## javax.microedition.io
Interface RandomAccessConnection

All Superinterfaces:
  Connection, DataInput, DataOutput, InputConnection, OutputConnection

All Known Subinterfaces:
  DirectoryConnection

public interface RandomAccessConnection
extends InputConnection, OutputConnection, DataInput, DataOutput

A connection to a random access memory

Method Summary
`long` | `getLength()` Get the length of the data
`long` | `getPosition()` Returns the current offset into the data.
`boolean` | `isSelected()` Test to see if a record in the collection is selected.
`int` | `read()` Reads a byte of data.
`int` | `read(byte[] b, int off, int len)` Reads up to `len` bytes of data into an array of bytes.
`void` | `seek(long pos)` Sets the position pointer offset, measured from the beginning of the data, at which the next read or write occurs.
`void` | `setLength(long len)` Set the length of the data (for truncation).
`void` | `write(byte[] b, int off, int len)` Writes `len` bytes from the specified byte array starting at offset `off` to the data
`void` | `write(int b)` Writes the specified byte to this file.

Methods inherited from interface javax.microedition.io.InputConnection
`openDataInputStream, openInputStream`

Methods inherited from interface javax.microedition.io.Connection
`close`

Methods inherited from interface javax.microedition.io.OutputConnection
`openDataOutputStream, openOutputStream`

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

Method Detail

### isSelected

    public boolean isSelected()
                       throws IOException

  Test to see if a record in the collection is selected. Until this is done none of the data access methods below will work. Some random access connection are always selected, but other ones, such as a MetadataConncetion may require a specific record to be selected before I/O can commence.
  Returns:
    true if the connection is selected, otherwise false.

### seek

    public void seek(long pos)
              throws IOException

  Sets the position pointer offset, measured from the beginning of the data, at which the next read or write occurs. The offset may be set beyond the end of the data. Setting the offset beyond the end of the data does not change the data length. The data length will change only by writing after the offset has been set beyond the end of the data.
  Parameters:
    `pos` - the offset position, measured in bytes from the beginning of the data, at which to set the position pointer.
  Throws:
    `IOException` - if `pos` is less than `0`, if an I/O error occurs, or there is an input or output stream open on the data.

### getPosition

    public long getPosition()
                     throws IOException

  Returns the current offset into the data.
  Returns:
    the offset from the beginning of the data, in bytes, at which the next read or write occurs.
  Throws:
    `IOException` - if an I/O error occurs.

### getLength

    public long getLength()
                   throws IOException

  Get the length of the data
  Returns:
    the length of the data

### setLength

    public void setLength(long len)
                   throws IOException

  Set the length of the data (for truncation).
  Parameters:
    `len` - the new length of the data

### read

    public int read()
             throws IOException

  Reads a byte of data. The byte is returned as an integer in the range 0 to 255 (`0x00-0x0ff`). This method blocks if no input is yet available.

  Returns:
    the next byte of data, or `-1` if the end of the data has been reached.
  Throws:
    `IOException` - if an I/O error occurs. Not thrown if end-of-data has been reached.

### read

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

  Reads up to `len` bytes of data into an array of bytes. This method blocks until at least one byte of input is available.
  Parameters:
    `b` - the buffer into which the data is read.
    `off` - the start offset of the data.
    `len` - the maximum number of bytes read.
  Returns:
    the total number of bytes read into the buffer, or `-1` if there is no more data because the end of the data has been reached.
  Throws:
    `IOException` - if an I/O error occurs.

### write

    public void write(int b)
               throws IOException

  Writes the specified byte to this file. The write starts at the current position pointer.
  Specified by:
    `write` in interface `DataOutput`
  Parameters:
    `b` - the `byte` to be written.
  Throws:
    `IOException` - if an I/O error occurs.

### write

    public void write(byte[] b,
                      int off,
                      int len)
               throws IOException

  Writes `len` bytes from the specified byte array starting at offset `off` to the data
  Specified by:
    `write` in interface `DataOutput`
  Parameters:
    `b` - the data.
    `off` - the start offset in the data.
    `len` - the number of bytes to write.
  Throws:
    `IOException` - if an I/O error occurs.

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