Package org.pipecraft.pipes.serialization

Class CSVDecoder<T>

java.lang.Object

org.pipecraft.pipes.serialization.CSVDecoder<T>

All Implemented Interfaces:

Closeable, AutoCloseable, ItemDecoder<T>

public class CSVDecoder<T>
extends Object
implements ItemDecoder<T>

An ItemDecoder that decodes CSV rows. Supports skipping header rows. Uses user defined function to create the java object from the string array parsed from an input line.

Author:

Eyal Schneider

Constructor Summary

Constructors

Constructor	Description
CSVDecoder(InputStream is, FailableFunction<String[],T,ValidationPipeException> itemDetextualizer)	Constructor Assumes UTF8, comma as a delimiter, no header rows and default read options (no compression)
CSVDecoder(InputStream is, FailableFunction<String[],T,ValidationPipeException> itemDetextualizer, int rowsToSkip)	Constructor Assumes UTF8, comma as a delimiter and default read options (no compression)
CSVDecoder(InputStream is, FailableFunction<String[],T,ValidationPipeException> itemDetextualizer, Charset charset, char delimiter, int rowsToSkip, FileReadOptions readOptions)	Constructor

Method Summary

Modifier and Type	Method	Description
void	close()
T	decode()	Reads and decodes the next object from the input stream.
static <R> DecoderFactory<R>	getFactory(FailableFunction<String[],R,ValidationPipeException> itemDetextualizer)
static <R> DecoderFactory<R>	getFactory(FailableFunction<String[],R,ValidationPipeException> itemDetextualizer, Charset charset, char delimiter, int rowsToSkip)

Methods inherited from class java.lang.Object

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

Constructor Detail

CSVDecoder

public CSVDecoder(InputStream is,
                  FailableFunction<String[],T,ValidationPipeException> itemDetextualizer,
                  Charset charset,
                  char delimiter,
                  int rowsToSkip,
                  FileReadOptions readOptions)
           throws IOException

Constructor

Parameters:

is - The input stream this decoder is bound to. Not expected to be buffered. Buffering is added internally.

itemDetextualizer - The logic that transforms a parsed line (String[]) into the corresponding java object. A column which is empty in the input is passed as null, unless it's an empty quoted string, which is passed as an empty string. Leading/trailing spaces from the input are kept (even if not quoted), so it's up to this function to decide what to do with them.

charset - The character encoding to assume when reading from the input stream

delimiter - The CSV delimiter character to use

rowsToSkip - The number of header rows to skip before parsing data lines. Non-negative.

readOptions - Input reading options (buffering/compression)

Throws:

IOException - In case of an IO error while preparing to read

CSVDecoder

public CSVDecoder(InputStream is,
                  FailableFunction<String[],T,ValidationPipeException> itemDetextualizer,
                  int rowsToSkip)
           throws IOException

Constructor Assumes UTF8, comma as a delimiter and default read options (no compression)

Parameters:

is - The input stream this decoder is bound to. Not expected to be buffered. Buffering is added internally.

itemDetextualizer - The logic that transforms a parsed line (String[]) into the corresponding java object. Columns which are empty in the input are passes as null. Leading/trailing spaces from the input are kept, so it's up to this function to decide what to do with them.

rowsToSkip - The number of header rows to skip before parsing data lines. Non-negative.

Throws:

IOException - In case of an IO error while preparing to read

CSVDecoder

public CSVDecoder(InputStream is,
                  FailableFunction<String[],T,ValidationPipeException> itemDetextualizer)
           throws IOException

Constructor Assumes UTF8, comma as a delimiter, no header rows and default read options (no compression)

Parameters:

is - The input stream this decoder is bound to. Not expected to be buffered. Buffering is added internally.

itemDetextualizer - The logic that transforms a parsed line (String[]) into the corresponding java object. Columns which are empty in the input are passes as null. Leading/trailing spaces from the input are kept, so it's up to this function to decide what to do with them.

Throws:

IOException - In case of an IO error while preparing to read

Method Detail

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in interface ItemDecoder<T>

Throws:

IOException

decode

public T decode()
         throws IOException,
                ValidationPipeException

Description copied from interface: ItemDecoder

Reads and decodes the next object from the input stream.

Specified by:

decode in interface ItemDecoder<T>

Returns:

The decoded item from the input stream provided on construction, or null if end of stream was reached

Throws:

IOException - In case of a read error

ValidationPipeException - In case that the data for decoding is illegal

getFactory

public static <R> DecoderFactory<R> getFactory(FailableFunction<String[],R,ValidationPipeException> itemDetextualizer,
                                               Charset charset,
                                               char delimiter,
                                               int rowsToSkip)

Parameters:

itemDetextualizer - The logic that transforms a parsed line (String[]) into the corresponding java object. Columns which are empty in the input are passes as null. Leading/trailing spaces from the input are kept, so it's up to this function to decide what to do with them.

charset - The character encoding to assume when reading from the input stream

delimiter - The CSV delimiter character to use

rowsToSkip - The number of header rows to skip before parsing data lines. Non-negative.

Returns:

A decoder factory producing CSV decoders based on the given settings

getFactory

public static <R> DecoderFactory<R> getFactory(FailableFunction<String[],R,ValidationPipeException> itemDetextualizer)

Parameters:

itemDetextualizer - The logic that transforms a parsed line (String[]) into the corresponding java object. Columns which are empty in the input are passes as null. Leading/trailing spaces from the input are kept, so it's up to this function to decide what to do with them.

Returns:

A decoder factory producing CSV decoders based on the given settings. Assumes UTF8, comma as delimiter and no header rows.