Class RandomAccessLineReader

java.lang.Object

net.thevpc.common.io.RandomAccessLineReader

All Implemented Interfaces:

AutoCloseable

public class RandomAccessLineReader
extends Object
implements AutoCloseable

Constructor Summary

Constructors

Constructor	Description
RandomAccessLineReader(File file)

Method Summary

Modifier and Type	Method	Description
void	backward()
void	close()
long	countLines()
long	countReadableLines()
long	fileLength()
void	forward()
long	getLastLineNumber()
long	getNextLineNumber()
RandomAccessOrientation	getOrientation()
boolean	hasMore()
final String	nextBackwardLine()
String	nextForwardLine()
String	readLine()
String	readLine(long offset)	read string at the given line number.
protected int	readNext()
protected int	readPrevious()
void	seekEnd()
void	seekLine(long offset)
void	seekStart()
void	setOrientation(RandomAccessOrientation o)
long	skipLines(long x)	skip x lines in the current orientation
protected final boolean	skipNextNewLine()
protected final boolean	skipPreviousNewLine()
void	switchOrientation()

Methods inherited from class Object

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

Constructor Details

RandomAccessLineReader

public RandomAccessLineReader(File file)
                       throws FileNotFoundException

Throws:

FileNotFoundException

Method Details

readLine

public String readLine(long offset)
                throws IOException

read string at the given line number. orientation will not be altered after this call even though offset may be <= getNextLineNumber()

Parameters:

offset - number of the line to read

Returns:

read line

Throws:

IOException - if i/O error

readLine

public String readLine()
                throws IOException

Throws:

IOException

skipLines

public long skipLines(long x)
               throws IOException

skip x lines in the current orientation

Parameters:

x - number of lines to skip. ignored if <= 0

Returns:

number of lines read

Throws:

IOException - when I/O error

nextForwardLine

public String nextForwardLine()
                       throws IOException

Throws:

IOException

nextBackwardLine

public final String nextBackwardLine()
                              throws IOException

Throws:

IOException

skipPreviousNewLine

protected final boolean skipPreviousNewLine()
                                     throws IOException

Throws:

IOException

skipNextNewLine

protected final boolean skipNextNewLine()
                                 throws IOException

Throws:

IOException

getNextLineNumber

public long getNextLineNumber()

getLastLineNumber

public long getLastLineNumber()

readNext

protected int readNext()
                throws IOException

Throws:

IOException

readPrevious

protected int readPrevious()
                    throws IOException

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Throws:

IOException

forward

public void forward()
             throws IOException

Throws:

IOException

backward

public void backward()
              throws IOException

Throws:

IOException

switchOrientation

public void switchOrientation()
                       throws IOException

Throws:

IOException

setOrientation

public void setOrientation(RandomAccessOrientation o)
                    throws IOException

Throws:

IOException

seekLine

public void seekLine(long offset)
              throws IOException

Throws:

IOException

seekStart

public void seekStart()
               throws IOException

Throws:

IOException

seekEnd

public void seekEnd()
             throws IOException

Throws:

IOException

fileLength

public long fileLength()
                throws IOException

Throws:

IOException

countLines

public long countLines()
                throws IOException

Throws:

IOException

countReadableLines

public long countReadableLines()
                        throws IOException

Throws:

IOException

getOrientation

public RandomAccessOrientation getOrientation()

hasMore

public boolean hasMore()
                throws IOException

Throws:

IOException