Package org.jrobin.core.jrrd

Class RRDFile

java.lang.Object

org.jrobin.core.jrrd.RRDFile

All Implemented Interfaces:

Constants

public class RRDFile
extends Object
implements Constants

This class is a quick hack to read information from an RRD file. Writing to RRD files is not currently supported. As I said, this is a quick hack. Some thought should be put into the overall design of the file IO.

Currently this can read RRD files that were generated on Solaris (Sparc) and Linux (x86).

Version:

$Revision$

Author:

Ciaran Treanor

Field Summary

Fields

Modifier and Type	Field	Description
(package private) int	alignment
(package private) boolean	bigEndian
(package private) byte[]	buffer
(package private) boolean	debug
(package private) RandomAccessFile	ras

Fields inherited from interface org.jrobin.core.jrrd.Constants

CF_NAM_SIZE, COOKIE, DS_NAM_SIZE, DST_SIZE, FLOAT_COOKIE, FLOAT_COOKIE_BIG_ENDIAN, FLOAT_COOKIE_LITTLE_ENDIAN, LAST_DS_LEN, VERSION, VERSION3

Constructor Summary

Constructors

Constructor	Description
RRDFile(File file)
RRDFile(String name)

Method Summary

Modifier and Type	Method	Description
(package private) int	align()
(package private) int	align(int boundary)
(package private) void	close()
(package private) int	getAlignment()
(package private) long	getFilePointer()
(package private) long	info()
(package private) boolean	isBigEndian()
(package private) double	readDouble()
(package private) int	readInt()
(package private) int	readInt(boolean dump)	Reads the next integer (4 or 8 bytes depending on alignment), advancing the file pointer and returns it If the alignment is 8-bytes (64-bit), then 8 bytes are read, but only the lower 4-bytes (32-bits) are returned.
(package private) String	readString(int maxLength)
(package private) void	skipBytes(int n)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

bigEndian

boolean bigEndian

debug

boolean debug

alignment

int alignment

ras

RandomAccessFile ras

buffer

byte[] buffer

Constructor Detail

RRDFile

RRDFile(String name)
 throws IOException,
        RrdException

Throws:

IOException

RrdException

RRDFile

RRDFile(File file)
 throws IOException,
        RrdException

Throws:

IOException

RrdException

Method Detail

isBigEndian

boolean isBigEndian()

getAlignment

int getAlignment()

readDouble

double readDouble()
           throws IOException,
                  RrdException

Throws:

IOException

RrdException

readInt

int readInt()
     throws IOException,
            RrdException

Throws:

IOException

RrdException

readInt

int readInt(boolean dump)
     throws IOException,
            RrdException

Reads the next integer (4 or 8 bytes depending on alignment), advancing the file pointer and returns it If the alignment is 8-bytes (64-bit), then 8 bytes are read, but only the lower 4-bytes (32-bits) are returned. The upper 4 bytes are ignored.

Returns:

the 32-bit integer read from the file

Throws:

IOException - - A file access error

RrdException - - Not enough bytes were left in the file to read the integer.

readString

String readString(int maxLength)
           throws IOException,
                  RrdException

Throws:

IOException

RrdException

skipBytes

void skipBytes(int n)
        throws IOException

Throws:

IOException

align

int align(int boundary)
   throws IOException

Throws:

IOException

align

int align()
   throws IOException

Throws:

IOException

info

long info()
   throws IOException

Throws:

IOException

getFilePointer

long getFilePointer()
             throws IOException

Throws:

IOException

close

void close()
    throws IOException

Throws:

IOException