Class Reader

java.lang.Object

io.github.kelsoncm.fwf.readers.Reader

All Implemented Interfaces:

Iterable<Map<String,Object>>, Iterator<Map<String,Object>>

public class Reader
extends Object
implements Iterable<Map<String,Object>>, Iterator<Map<String,Object>>

Sequential reader for Fixed Width Files.

Implements Iterable and Iterator to stream fixed-width records line by line as structured maps. Validates line size and line break delimiters during initialization.

Constructor Summary

Constructors

Constructor	Description
Reader(Object iterable, FileDescriptor fileDescriptor)	Constructs a new Reader defaulting to newline delimiter "\n\r".
Reader(Object iterable, FileDescriptor fileDescriptor, String newline)	Constructs a new Reader with a content source, file descriptor, and newline delimiter.

Method Summary

Modifier and Type	Method	Description
int	getLineNum()	Gets the 1-based index of the line currently being processed.
int	getLinesCount()	Gets the total number of lines in the file.
boolean	hasNext()	Checks if more lines remain to be read.
Iterator<Map<String,Object>>	iterator()	Returns an iterator over the parsed row maps.
Map<String,Object>	next()	Reads and parses the next line into a map of column names to parsed values.

Methods inherited from class Object

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

Methods inherited from interface Iterable

forEach, spliterator

Methods inherited from interface Iterator

forEachRemaining, remove

Constructor Details

Reader

public Reader(Object iterable,
 FileDescriptor fileDescriptor,
 String newline)

Constructs a new Reader with a content source, file descriptor, and newline delimiter.

Parameters:

iterable - source object (String, List of Strings, InputStream, or java.io.Reader)

fileDescriptor - non-null FileDescriptor

newline - newline delimiter string ("\n", "\r", or "\n\r")

Throws:

IllegalArgumentException - if any argument is invalid or line sizes do not match

Reader

public Reader(Object iterable,
 FileDescriptor fileDescriptor)

Constructs a new Reader defaulting to newline delimiter "\n\r".

Parameters:

iterable - source object

fileDescriptor - non-null FileDescriptor

Method Details

getLinesCount

public int getLinesCount()

Gets the total number of lines in the file.

Returns:

line count

getLineNum

public int getLineNum()

Gets the 1-based index of the line currently being processed.

Returns:

current 1-based line number

iterator

public Iterator<Map<String,Object>> iterator()

Returns an iterator over the parsed row maps.

Specified by:

iterator in interface Iterable<Map<String,Object>>

Returns:

iterator

hasNext

public boolean hasNext()

Checks if more lines remain to be read.

Specified by:

hasNext in interface Iterator<Map<String,Object>>

Returns:

true if lines remain, false otherwise

next

public Map<String,Object> next()

Reads and parses the next line into a map of column names to parsed values.

Specified by:

next in interface Iterator<Map<String,Object>>

Returns:

parsed row map

Throws:

NoSuchElementException - if no more lines remain