Package fj.data

Class IOFunctions

java.lang.Object

fj.data.IOFunctions

public final class IOFunctions
extends java.lang.Object

IO monad for processing files, with main methods enumFileLines(java.io.File, fj.data.Option<java.nio.charset.Charset>, fj.data.Iteratee.IterV<java.lang.String, A>), enumFileChars(java.io.File, fj.data.Option<java.nio.charset.Charset>, fj.data.Iteratee.IterV<java.lang.Character, A>) and enumFileCharChunks(java.io.File, fj.data.Option<java.nio.charset.Charset>, fj.data.Iteratee.IterV<char[], A>) (the latter one is the fastest as char chunks read from the file are directly passed to the iteratee without indirection in between).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	IOFunctions.CharChunkReader<A>
private static class	IOFunctions.CharChunkReader2<A>
private static class	IOFunctions.LineReader<A>

Field Summary

Fields

Modifier and Type	Field	Description
static F<java.io.Reader,IO<Unit>>	closeReader
private static int	DEFAULT_BUFFER_SIZE
static IO<Unit>	ioUnit
static java.io.BufferedReader	stdinBufferedReader

Constructor Summary

Constructors

Modifier	Constructor	Description
private	IOFunctions()

Method Summary

Modifier and Type	Method	Description
static <A,B> IO<B>	append(IO<A> io1, IO<B> io2)
static <A,B> IO<B>	apply(IO<A> io, IO<F<A,B>> iof)
static <A,B> IO<B>	as(IO<A> io, B b)
static <A,B> IO<B>	bind(IO<A> io, F<A,IO<B>> f)
static <A,B,C> IO<C>	bracket(IO<A> init, F<A,IO<B>> fin, F<A,IO<C>> body)
static IO<java.io.BufferedReader>	bufferedReader(java.io.File f, Option<java.nio.charset.Charset> encoding)
static <A> F<java.io.Reader,F<Iteratee.IterV<char[],A>,IO<Iteratee.IterV<char[],A>>>>	charChunkReader()	A function that feeds an iteratee with character chunks read from a Reader (char[] of size DEFAULT_BUFFER_SIZE).
static <A> F<java.io.Reader,F<Iteratee.IterV<java.lang.Character,A>,IO<Iteratee.IterV<java.lang.Character,A>>>>	charChunkReader2()	A function that feeds an iteratee with characters read from a Reader (chars are read in chunks of size DEFAULT_BUFFER_SIZE).
static IO<Unit>	closeReader(java.io.Reader r)
static <A> IO<Iteratee.IterV<char[],A>>	enumFileCharChunks(java.io.File f, Option<java.nio.charset.Charset> encoding, Iteratee.IterV<char[],A> i)	An IO monad that reads char chunks from the given file and passes them to the given iteratee.
static <A> IO<Iteratee.IterV<java.lang.Character,A>>	enumFileChars(java.io.File f, Option<java.nio.charset.Charset> encoding, Iteratee.IterV<java.lang.Character,A> i)	An IO monad that reads char chunks from the given file and passes single chars to the given iteratee.
static <A> IO<Iteratee.IterV<java.lang.String,A>>	enumFileLines(java.io.File f, Option<java.nio.charset.Charset> encoding, Iteratee.IterV<java.lang.String,A> i)	An IO monad that reads lines from the given file (using a BufferedReader) and passes lines to the provided iteratee.
static IO<java.io.Reader>	fileReader(java.io.File f, Option<java.nio.charset.Charset> encoding)
static <A,B> IO<B>	flatMap(IO<A> io, F<A,IO<B>> f)
static <A> IO<A>	fromF(F0<A> p)
static <A> IO<A>	fromTry(Try0<A,? extends java.io.IOException> t)
static IO<LazyString>	getContents()
static IO<Unit>	interact(F<LazyString,LazyString> f)
static IO<Unit>	interactWhile(F<java.lang.String,java.lang.Boolean> condition, F<java.lang.String,java.lang.String> transform)	Read lines from stdin until condition is not met, transforming each line and printing the result to stdout.
static <A> IO<A>	join(IO<IO<A>> io1)
static <A> IO<A>	lazy(F<Unit,A> f)
static <A> IO<A>	lazy(F0<A> p)
static <A> SafeIO<A>	lazySafe(F<Unit,A> f)
static <A> SafeIO<A>	lazySafe(F0<A> f)
static <A,B> IO<A>	left(IO<A> io1, IO<B> io2)
static <A,B,C> IO<C>	liftM2(IO<A> ioa, IO<B> iob, F2<A,B,C> f)
static <A> F<java.io.BufferedReader,F<Iteratee.IterV<java.lang.String,A>,IO<Iteratee.IterV<java.lang.String,A>>>>	lineReader()	A function that feeds an iteratee with lines read from a BufferedReader.
static <A,B> IO<B>	map(IO<A> io, F<A,B> f)
static <A> P1<Validation<java.io.IOException,A>>	p(IO<A> io)
static <A> IO<State<java.io.BufferedReader,Validation<java.io.IOException,java.lang.String>>>	readerState()
static <A> IO<List<A>>	replicateM(IO<A> ioa, int n)
static <A> A	runSafe(IO<A> io)	Run io, rethrowing any IOException wrapped in a RuntimeException
static <A> IO<List<A>>	sequence(List<IO<A>> list)	Evaluate each action in the sequence from left to right, and collect the results.
static <A> IO<Stream<A>>	sequence(Stream<IO<A>> stream)
static <A> IO<Stream<A>>	sequenceWhile(Stream<IO<A>> stream, F<A,java.lang.Boolean> f)
static <A> IO<Stream<A>>	sequenceWhileEager(Stream<IO<A>> stream, F<A,java.lang.Boolean> f)
static IO<java.lang.String>	stdinReadLine()
static IO<Unit>	stdoutPrint(java.lang.String s)
static IO<Unit>	stdoutPrintln(java.lang.String s)
static <A> SafeIO<A>	toSafe(IO<A> io)	Convert io to a SafeIO, throwing any IOException wrapped inside a RuntimeException
static <A> SafeIO<Validation<java.io.IOException,A>>	toSafeValidation(IO<A> io)
static <A> Try0<A,java.io.IOException>	toTry(IO<A> io)
static <A> IO<A>	unit(A a)
static IO<Unit>	unless(java.lang.Boolean b, IO<Unit> io)
static <A> IO<Unit>	voided(IO<A> io)
static IO<Unit>	when(java.lang.Boolean b, IO<Unit> io)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_BUFFER_SIZE

private static final int DEFAULT_BUFFER_SIZE

See Also:

Constant Field Values

closeReader

public static final F<java.io.Reader,IO<Unit>> closeReader

ioUnit

public static final IO<Unit> ioUnit

stdinBufferedReader

public static final java.io.BufferedReader stdinBufferedReader

Constructor Detail

IOFunctions

private IOFunctions()

Method Detail

toTry

public static <A> Try0<A,java.io.IOException> toTry(IO<A> io)

p

public static <A> P1<Validation<java.io.IOException,A>> p(IO<A> io)

fromF

public static <A> IO<A> fromF(F0<A> p)

fromTry

public static <A> IO<A> fromTry(Try0<A,? extends java.io.IOException> t)

toSafe

public static <A> SafeIO<A> toSafe(IO<A> io)

Convert io to a SafeIO, throwing any IOException wrapped inside a RuntimeException

Parameters:

io -

runSafe

public static <A> A runSafe(IO<A> io)

Run io, rethrowing any IOException wrapped in a RuntimeException

Parameters:

io -

closeReader

public static IO<Unit> closeReader(java.io.Reader r)

enumFileLines

public static <A> IO<Iteratee.IterV<java.lang.String,A>> enumFileLines(java.io.File f,
                                                                             Option<java.nio.charset.Charset> encoding,
                                                                             Iteratee.IterV<java.lang.String,A> i)

An IO monad that reads lines from the given file (using a BufferedReader) and passes lines to the provided iteratee. May not be suitable for files with very long lines, consider to use enumFileCharChunks(java.io.File, fj.data.Option<java.nio.charset.Charset>, fj.data.Iteratee.IterV<char[], A>) or enumFileChars(java.io.File, fj.data.Option<java.nio.charset.Charset>, fj.data.Iteratee.IterV<java.lang.Character, A>) as an alternative.

Parameters:

f - the file to read, must not be null

encoding - the encoding to use, Option.none() means platform default

i - the iteratee that is fed with lines read from the file

enumFileCharChunks

public static <A> IO<Iteratee.IterV<char[],A>> enumFileCharChunks(java.io.File f,
                                                                        Option<java.nio.charset.Charset> encoding,
                                                                        Iteratee.IterV<char[],A> i)

An IO monad that reads char chunks from the given file and passes them to the given iteratee.

Parameters:

f - the file to read, must not be null

encoding - the encoding to use, Option.none() means platform default

i - the iteratee that is fed with char chunks read from the file

enumFileChars

public static <A> IO<Iteratee.IterV<java.lang.Character,A>> enumFileChars(java.io.File f,
                                                                                Option<java.nio.charset.Charset> encoding,
                                                                                Iteratee.IterV<java.lang.Character,A> i)

An IO monad that reads char chunks from the given file and passes single chars to the given iteratee.

Parameters:

f - the file to read, must not be null

encoding - the encoding to use, Option.none() means platform default

i - the iteratee that is fed with chars read from the file

bufferedReader

public static IO<java.io.BufferedReader> bufferedReader(java.io.File f,
                                                        Option<java.nio.charset.Charset> encoding)

fileReader

public static IO<java.io.Reader> fileReader(java.io.File f,
                                            Option<java.nio.charset.Charset> encoding)

bracket

public static <A,B,C> IO<C> bracket(IO<A> init,
                                                F<A,IO<B>> fin,
                                                F<A,IO<C>> body)

unit

public static <A> IO<A> unit(A a)

lazy

public static <A> IO<A> lazy(F0<A> p)

lazy

public static <A> IO<A> lazy(F<Unit,A> f)

lazySafe

public static <A> SafeIO<A> lazySafe(F<Unit,A> f)

lazySafe

public static <A> SafeIO<A> lazySafe(F0<A> f)

lineReader

public static <A> F<java.io.BufferedReader,F<Iteratee.IterV<java.lang.String,A>,IO<Iteratee.IterV<java.lang.String,A>>>> lineReader()

A function that feeds an iteratee with lines read from a BufferedReader.

charChunkReader

public static <A> F<java.io.Reader,F<Iteratee.IterV<char[],A>,IO<Iteratee.IterV<char[],A>>>> charChunkReader()

A function that feeds an iteratee with character chunks read from a Reader (char[] of size DEFAULT_BUFFER_SIZE).

charChunkReader2

public static <A> F<java.io.Reader,F<Iteratee.IterV<java.lang.Character,A>,IO<Iteratee.IterV<java.lang.Character,A>>>> charChunkReader2()

A function that feeds an iteratee with characters read from a Reader (chars are read in chunks of size DEFAULT_BUFFER_SIZE).

map

public static <A,B> IO<B> map(IO<A> io,
                                    F<A,B> f)

as

public static <A,B> IO<B> as(IO<A> io,
                                   B b)

voided

public static <A> IO<Unit> voided(IO<A> io)

bind

public static <A,B> IO<B> bind(IO<A> io,
                                     F<A,IO<B>> f)

when

public static IO<Unit> when(java.lang.Boolean b,
                            IO<Unit> io)

unless

public static IO<Unit> unless(java.lang.Boolean b,
                              IO<Unit> io)

sequence

public static <A> IO<List<A>> sequence(List<IO<A>> list)

Evaluate each action in the sequence from left to right, and collect the results.

sequence

public static <A> IO<Stream<A>> sequence(Stream<IO<A>> stream)

join

public static <A> IO<A> join(IO<IO<A>> io1)

toSafeValidation

public static <A> SafeIO<Validation<java.io.IOException,A>> toSafeValidation(IO<A> io)

append

public static <A,B> IO<B> append(IO<A> io1,
                                       IO<B> io2)

left

public static <A,B> IO<A> left(IO<A> io1,
                                     IO<B> io2)

flatMap

public static <A,B> IO<B> flatMap(IO<A> io,
                                        F<A,IO<B>> f)

interactWhile

public static IO<Unit> interactWhile(F<java.lang.String,java.lang.Boolean> condition,
                                     F<java.lang.String,java.lang.String> transform)

Read lines from stdin until condition is not met, transforming each line and printing the result to stdout.

Parameters:

condition - Read lines until a line does not satisfy condition

transform - Function to change line value

sequenceWhileEager

public static <A> IO<Stream<A>> sequenceWhileEager(Stream<IO<A>> stream,
                                                   F<A,java.lang.Boolean> f)

sequenceWhile

public static <A> IO<Stream<A>> sequenceWhile(Stream<IO<A>> stream,
                                              F<A,java.lang.Boolean> f)

apply

public static <A,B> IO<B> apply(IO<A> io,
                                      IO<F<A,B>> iof)

liftM2

public static <A,B,C> IO<C> liftM2(IO<A> ioa,
                                               IO<B> iob,
                                               F2<A,B,C> f)

replicateM

public static <A> IO<List<A>> replicateM(IO<A> ioa,
                                         int n)

readerState

public static <A> IO<State<java.io.BufferedReader,Validation<java.io.IOException,java.lang.String>>> readerState()

stdinReadLine

public static IO<java.lang.String> stdinReadLine()

stdoutPrintln

public static IO<Unit> stdoutPrintln(java.lang.String s)

stdoutPrint

public static IO<Unit> stdoutPrint(java.lang.String s)

getContents

public static IO<LazyString> getContents()

interact

public static IO<Unit> interact(F<LazyString,LazyString> f)