Atitit. Attilax Summary of high performance traverse text file lines

Atitit. High performance Traverse text file lines Attilax Summary

There are several common methods for file reading and writing 1

Usually io reads 2.5s 1

NiO reads Perhaps the higher the : 2

NIO is typically in Reactor mode, andAIO typically uses proactor mode 2

Java support for bio, NIO, AIO: 2

BIO, NIO, AIO Scenarios for analysis: 3

There are several common ways to read and write files:

1, Byte Read and write (inputstream/outputstream)

2, character reading (filereader/filewriter)

3, line read (bufferedreader/bufferedwriter)

File size : 110m

Line :: 55w

Author:: Old Wow's paw attilax Ayron, email:[email protected]

Reprint please indicate source: Http://blog.csdn.net/attilax

UsuallyioRead2.5s

Public Static void Main (string[] args) {

Substancesaharalookandfeel

Long T1=new Date (). GetTime ();

Filex FX=new Filex ();

FX. Readperline ("E:\\ui.rar.txt", "GBK", new scannerlinefilter4mail ());

System. out. println ("--f");

// list<string> Li = Filex.read2list_filtemptynstartspace ("C:\\em.txt");

System. out. println (new Date (). GetTime ()-T1);

}

Public class Scannerlinefilter4mail implements Closure {

int n= 0;

@Override

Public Object execute (Object arg0) throws Exception {

n+ +;

if (n%10000==0)

System. out. println ("-----:"+n);

//System.out.println (arg0);

return null;

}

Niothe higher the reading May be..

One result: NiO spends about one-third less than bio. (from site)

Niousually withReactormode,AIOusually withProactorMode

。 AIO simplifies programming, stream reads and writes are done by the OS, and does not need to traverse selector like NiO. Windows-based IOCP implementation Aio,linux only the Eppoll simulation implements AIO.

Prior to JAVA7, the JDK supported only NiO and bio and supported AIO from 7 onwards.

Java support for bio, NIO, Aio:

·

Java BIO: Synchronization and blocking, the server implementation mode for a connection to a thread, that is, the client has a connection request when the server needs to start a thread to process, if the connection does not do anything will cause unnecessary thread overhead, of course, can be improved through the thread pool mechanism.

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·

Java NIO: Synchronous non-blocking, the server implementation mode is a request for a thread, that is, the connection request sent by the client is registered on the multiplexer, and the multiplexer polls to the connection with an I/O request to start a thread for processing.

·

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Java AIO (nio.2): Asynchronous non-blocking, server implementation mode for a valid request for a thread, the client I/O requests are completed by the OS before notifying the server application to start the thread for processing,

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BIO, NIO, AIO application scenario analysis:

·

The bio method is suitable for a small and fixed number of connections, which requires a high level of server resources, and is limited to applications, JDK1.4 the only choice before, but the program is intuitive and easy to understand.

·

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The NIO approach is suitable for architectures with a large number of connections and short (light-operated) connections, such as chat servers, which are limited to applications, and are more complex to program, and JDK1.4 begin to support.

·

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AIO mode allows for a number of connections and long-connected (re-operation) of the architecture, such as the album server, full call to the OS to participate in concurrent operations, programming more complex, JDK7 began to support.

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Java NIO Series Tutorials - Special manuscript -iteye essence . htm

Java NIO and BIO Statistics file line number performance comparison - Open source China Community . htm

BIO, NIO, AIO(EXT) - Zhao Lei's blog -iteye technology website . htm

Java BIO,NIO,AIO Learning - power comes from the love of absolute sincerity! -51CTO technology blog . htm

Java NIO Series Tutorials - Special manuscript -iteye essence . htm

Atitit. Attilax Summary of high performance traverse text file lines