org.apache.commons.io.input

类 ReversedLinesFileReader

java.lang.Object

org.apache.commons.io.input.ReversedLinesFileReader

所有已实现的接口:

Closeable, AutoCloseable

public class ReversedLinesFileReader
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.

从以下版本开始:

2.2

构造器概要

构造器

构造器和说明
ReversedLinesFileReader(File file) 已过时。 2.5 use ReversedLinesFileReader(File, Charset) instead
ReversedLinesFileReader(File file, Charset charset) Creates a ReversedLinesFileReader with default block size of 4KB and the specified encoding.
ReversedLinesFileReader(File file, int blockSize, Charset encoding) Creates a ReversedLinesFileReader with the given block size and encoding.
ReversedLinesFileReader(File file, int blockSize, String encoding) Creates a ReversedLinesFileReader with the given block size and encoding.

方法概要

限定符和类型	方法和说明
void	close() Closes underlying resources.
String	readLine() Returns the lines of the file from bottom to top.

从类继承的方法 java.lang.Object

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

构造器详细资料

ReversedLinesFileReader

@Deprecated
public ReversedLinesFileReader(File file)
                                     throws IOException

已过时。 2.5 use ReversedLinesFileReader(File, Charset) instead

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

参数:

file - the file to be read

抛出:

IOException - if an I/O error occurs

ReversedLinesFileReader

public ReversedLinesFileReader(File file,
                               Charset charset)
                        throws IOException

Creates a ReversedLinesFileReader with default block size of 4KB and the specified encoding.

参数:

file - the file to be read

charset - the encoding to use

抛出:

IOException - if an I/O error occurs

从以下版本开始:

2.5

ReversedLinesFileReader

public ReversedLinesFileReader(File file,
                               int blockSize,
                               Charset encoding)
                        throws IOException

Creates a ReversedLinesFileReader with the given block size and encoding.

参数:

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

抛出:

IOException - if an I/O error occurs

从以下版本开始:

2.3

ReversedLinesFileReader

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

Creates a ReversedLinesFileReader with the given block size and encoding.

参数:

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

抛出:

IOException - if an I/O error occurs

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

方法详细资料

readLine

public String readLine()
                throws IOException

Returns the lines of the file from bottom to top.

返回:

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

抛出:

IOException - if an I/O error occurs

close

public void close()
           throws IOException

Closes underlying resources.

指定者:

close 在接口中 Closeable

指定者:

close 在接口中 AutoCloseable

抛出:

IOException - if an I/O error occurs