Package org.apache.ignite.internal.util.io

Class GridReversedLinesFileReader

java.lang.Object

org.apache.ignite.internal.util.io.GridReversedLinesFileReader

All Implemented Interfaces:

Closeable, AutoCloseable

public class GridReversedLinesFileReader
extends Object
implements Closeable

Reads lines in a file reversely (similar to a BufferedReader, but starting at the last line). Useful for e.g. searching in log files.

Constructor Summary

Constructors

Constructor	Description
GridReversedLinesFileReader(File file)	Creates a ReverseLineReader with default block size of 4KB and the platform's default encoding.
GridReversedLinesFileReader(File file, int blockSize, String encoding)	Creates a ReverseLineReader with the given block size and encoding.
GridReversedLinesFileReader(File file, int blockSize, Charset charset)	Creates a ReverseLineReader with the given block size and encoding.

Method Summary

Modifier and Type	Method	Description
void	close()	Closes underlying resources.
String	readLine()	Returns the lines of the file from bottom to top.

Methods inherited from class java.lang.Object

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

Constructor Detail

GridReversedLinesFileReader

public GridReversedLinesFileReader(File file)
                            throws IOException

Creates a ReverseLineReader with default block size of 4KB and the platform's default encoding.

Parameters:

file - the file to be read

Throws:

IOException - if an I/O error occurs

GridReversedLinesFileReader

public GridReversedLinesFileReader(File file,
                                   int blockSize,
                                   Charset charset)
                            throws IOException

Creates a ReverseLineReader with the given block size and encoding.

Parameters:

file - the file to be read

blockSize - size of the internal buffer (for ideal performance this should match with the block size of the underlying file system).

charset - the encoding of the file

Throws:

IOException - if an I/O error occurs

Since:

2.3

GridReversedLinesFileReader

public GridReversedLinesFileReader(File file,
                                   int blockSize,
                                   String encoding)
                            throws IOException

Creates a ReverseLineReader with the given block size and encoding.

Parameters:

file - the file to be read

blockSize - size of the internal buffer (for ideal performance this should match with the block size of the underlying file system).

encoding - the encoding of the file

Throws:

IOException - if an I/O error occurs

UnsupportedCharsetException - thrown instead of UnsupportedEncodingException in version 2.2 if the encoding is not supported.

Method Detail

readLine

public String readLine()
                throws IOException

Returns the lines of the file from bottom to top.

Returns:

the next line or null if the start of the file is reached

Throws:

IOException - if an I/O error occurs

close

public void close()
           throws IOException

Closes underlying resources.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException - if an I/O error occurs