Module de.siegmar.fastcsv

Package de.siegmar.fastcsv.reader

Class CsvReader<T>

java.lang.Object

de.siegmar.fastcsv.reader.CsvReader<T>

Type Parameters:

T - the type of the CSV record.

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, java.lang.Iterable<T>

public final class CsvReader<T>
extends java.lang.Object
implements java.lang.Iterable<T>, java.io.Closeable

This is the main class for reading CSV data.

The CSV records are read iteratively, regardless of whether the Iterable, the Iterator, or the Stream is used. Once all records are read, the data is consumed. If you need to repeatedly read records, you should collect the records in a List or another collection.

Example use:

Example for named records:

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CsvReader.CsvReaderBuilder	This builder is used to create configured instances of CsvReader.
private class	CsvReader.CsvRecordIterator
private class	CsvReader.CsvSpliterator

Field Summary

Fields

Modifier and Type	Field	Description
private CsvCallbackHandler<T>	callbackHandler
private CommentStrategy	commentStrategy
private CsvParser	csvParser
private CloseableIterator<T>	csvRecordIterator
private int	firstRecordFieldCount
private boolean	ignoreDifferentFieldCount
private boolean	skipEmptyLines

Constructor Summary

Constructors

Constructor	Description
CsvReader(CsvParser csvParser, CsvCallbackHandler<T> callbackHandler, CommentStrategy commentStrategy, boolean skipEmptyLines, boolean ignoreDifferentFieldCount)

Method Summary

Modifier and Type	Method	Description
static CsvReader.CsvReaderBuilder	builder()	Constructs a CsvReader.CsvReaderBuilder to configure and build instances of this class.
private java.lang.String	buildExceptionMessage()
private void	checkFieldCountConsistency(int fieldCount)
void	close()
private T	fetch()
private T	fetchRecord()
CloseableIterator<T>	iterator()	Returns an iterator over elements of type CsvRecord.
private T	processRecord()
void	skipLines(int lineCount)	Skips the specified number of lines.
int	skipLines(java.util.function.Predicate<java.lang.String> predicate, int maxLines)	Skip lines until the specified predicate matches.
java.util.Spliterator<T>	spliterator()	Returns a Spliterator over elements of type CsvRecord.
java.util.stream.Stream<T>	stream()	Returns a new sequential Stream with this reader as its source.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach

Field Detail

csvParser

private final CsvParser csvParser

callbackHandler

private final CsvCallbackHandler<T> callbackHandler

commentStrategy

private final CommentStrategy commentStrategy

skipEmptyLines

private final boolean skipEmptyLines

ignoreDifferentFieldCount

private final boolean ignoreDifferentFieldCount

csvRecordIterator

private final CloseableIterator<T> csvRecordIterator

firstRecordFieldCount

private int firstRecordFieldCount

Constructor Detail

CsvReader

CsvReader(CsvParser csvParser,
          CsvCallbackHandler<T> callbackHandler,
          CommentStrategy commentStrategy,
          boolean skipEmptyLines,
          boolean ignoreDifferentFieldCount)

Method Detail

builder

public static CsvReader.CsvReaderBuilder builder()

Constructs a CsvReader.CsvReaderBuilder to configure and build instances of this class.

Returns:

a new CsvReader.CsvReaderBuilder instance.

skipLines

public void skipLines(int lineCount)

Skips the specified number of lines.

The setting CsvReader.CsvReaderBuilder.skipEmptyLines(boolean) has no effect on this method.

Parameters:

lineCount - the number of lines to skip.

Throws:

java.lang.IllegalArgumentException - if lineCount is negative.

java.io.UncheckedIOException - if an I/O error occurs.

CsvParseException - if not enough lines are available to skip.

skipLines

public int skipLines(java.util.function.Predicate<java.lang.String> predicate,
                     int maxLines)

Skip lines until the specified predicate matches. The line that matches the predicate is not skipped.

The method returns the number of lines actually skipped.

The setting CsvReader.CsvReaderBuilder.skipEmptyLines(boolean) has no effect on this method.

Parameters:

predicate - the predicate to match the lines.

maxLines - the maximum number of lines to skip.

Returns:

the number of lines actually skipped.

Throws:

java.lang.NullPointerException - if predicate is null.

java.io.UncheckedIOException - if an I/O error occurs.

CsvParseException - if no matching line is found within the maximum limit of maxLines.

iterator

public CloseableIterator<T> iterator()

Returns an iterator over elements of type CsvRecord.

The returned iterator is not thread-safe. Remember to close the returned iterator when you're done. Alternatively, use stream().
This method is idempotent and can be called multiple times.

Specified by:

iterator in interface java.lang.Iterable<T>

Returns:

an iterator over the CSV records.

Throws:

java.io.UncheckedIOException - if an I/O error occurs.

CsvParseException - if any other problem occurs when parsing the CSV data.

See Also:

stream()

spliterator

public java.util.Spliterator<T> spliterator()

Returns a Spliterator over elements of type CsvRecord.

The returned spliterator is not thread-safe. Remember to invoke close() when you're done. Alternatively, use stream().
This method is idempotent and can be called multiple times.

Specified by:

spliterator in interface java.lang.Iterable<T>

Returns:

a spliterator over the CSV records.

Throws:

java.io.UncheckedIOException - if an I/O error occurs.

CsvParseException - if any other problem occurs when parsing the CSV data.

See Also:

stream()

stream

public java.util.stream.Stream<T> stream()

Returns a new sequential Stream with this reader as its source.

The returned stream is not thread-safe. Remember to close the returned stream when you're done. Closing the stream will also close this reader.
This method can be called multiple times, although it creates a new stream each time.
The stream is not reusable after it has been closed.

Returns:

a sequential Stream over the CSV records.

Throws:

java.io.UncheckedIOException - if an I/O error occurs.

CsvParseException - if any other problem occurs when parsing the CSV data.

See Also:

iterator()

fetchRecord

private T fetchRecord()
               throws java.io.IOException

Throws:

java.io.IOException

processRecord

private T processRecord()

checkFieldCountConsistency

private void checkFieldCountConsistency(int fieldCount)

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Throws:

java.io.IOException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

fetch

private T fetch()

buildExceptionMessage

private java.lang.String buildExceptionMessage()