THE PACKAGE JAVA.IO

java.io.RandomAccessFile

22.23

If

mode

 is

"rw"

, then the file may be both read and written. If

mode

 is

"r"

,

then the file may be read but may not be written (every write method for this

object will simply throw an

IOException

). If

mode

 is not

"r"

 or

"rw"

, then this

constructor throws an

IllegalArgumentException

.

22.23.2

public RandomAccessFile(File file, String mode)

throws SecurityException, IOException,

IllegalArgumentException

This constructor initializes a newly created

RandomAccessFile

 by opening a

connection to an actual file, the file named by

file

 in the file system. A new

FileDescriptor

 object is created to represent this file connection.

First, if there is a security manager, its

checkRead

 method ( 20.17.19) is

called with the path represented by the

file

 argument as its argument.

Next, if

mode

 is

"rw"

 and there is a security manager, its

checkWrite

 method

( 20.17.21) is called with the path represented by the

file

 argument as its argu 

ment.

If

mode

 is

"rw"

, then the file may be both read and written. If

mode

 is

"r"

,

then the file may be read but may not be written (every write method for this

object will simply throw an

IOException

). If

mode

 is not

"r"

 or

"rw"

, then this

constructor throws an

IllegalArgumentException

.

22.23.3

public final FileDescriptor getFD() throws IOException

This method returns the

FileDescriptor

 object ( 22.26) that represents the con 

nection to the actual file in the file system being used by this

RandomAccessFile

.

22.23.4

public long getFilePointer() throws IOException

The current file pointer for this random access file is returned. An

IOException

 is

thrown if the file pointer cannot be read for any reason.

22.23.5

public void seek(long pos) throws IOException

The file pointer for this random access file is set to

pos

, which is a position within

the file, measured in bytes. Position

0

 is the start of the file. An

IOException

 is

thrown if

pos

 is less than zero or greater than the length of the file, or if the file

pointer cannot be set for any other reason.

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