Package csv.impl

Class CSVWriter

java.lang.Object

csv.impl.AbstractTableWriter

csv.impl.AbstractStreamTableWriter

csv.impl.CSVWriter

All Implemented Interfaces:

TableWriter

public class CSVWriter
extends AbstractStreamTableWriter

Implements functionality for writing CSV streams.

Example:

java.io.File f = new java.io.File("csv-test.csv");
CSVWriter out = new CSVWriter(f);
out.printRow(new Object[] { "0:0", "0:1", "0:2" });
out.printRow(new Object[] { "1:0", "1:1", "1:2" });
out.close();

Author:

RalphSchuster

Constructor Summary

Constructors

Constructor	Description
CSVWriter()	Default constructor.
CSVWriter(File file)	Constructor for writing into a file.
CSVWriter(OutputStream out)	Constructor for writing into a stream.
CSVWriter(Writer out)	Deprecated. Use CSVWriter(OutputStream) instead.
CSVWriter(Writer out, boolean flush)	Deprecated.
CSVWriter(String file)	Constructor for writing into a file.

Method Summary

Modifier and Type	Method	Description
void	close()	Closes the underlying stream.
protected boolean	columnNeedsDelimiting(String s)	Decides if a column value needs to be wrapped with delimiters.
int	getColumnCount()	Returns the columns written to the stream.
String	getColumnDelimiter()	Returns the column delimiter to be used.
char	getColumnSeparator()	Returns the column separator to be used.
char	getCommentChar()	Returns the character used for indicating comments
String	getRowSeparator()	Returns the row separator to be used.
PrintWriter	getWriter()	Returns the underlying stream.
protected void	init()	Initializes the writer.
boolean	isColumnDelimiterRequired()	Returns whether column delimiters are always required.
protected String	prepareColumnValue(String s)	Replaces all occurrences of the delimiter by doubling it.
String	prepareComment(String comment)	Formats a comment for printing
String	prepareRow(Object[] columns)	Formats a row for CSV output.
void	printComment(String comment)	Prints a comment into the CSV stream.
void	printComment(String comment, int row, int column)	Prints a comment into the stream.
void	printRow(Object[] columns)	Prints a new row into the CSV file.
void	setColumnDelimiter(String s)	Sets the column delimiter to be used.
void	setColumnDelimiterRequired(boolean b)	Sets if column separators are always required or not.
void	setColumnSeparator(char s)	Sets the column separator to be used.
void	setCommentChar(char commentChar)	Sets the character to be used for indicating comments
void	setRowSeparator(String s)	Sets the row separator to be used.

Methods inherited from class csv.impl.AbstractStreamTableWriter

createOutputStreamWriter, createWriter, getCharsetEncoder, getOutputStream, setCharset, setCharset, setCharsetEncoder, setOutputStream

Methods inherited from class csv.impl.AbstractTableWriter

convert, convert, getRowCount, getTypeConversionHandler, incrementRowCount, printRow, printRow, printRow, registerTypeConversionHandler, unregisterTypeConversionHandler

Methods inherited from class java.lang.Object

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

Constructor Detail

CSVWriter

public CSVWriter()

Default constructor.

CSVWriter

public CSVWriter(File file)
          throws IOException

Constructor for writing into a file.

Parameters:

file - file

Throws:

IOException - when an exception occurs

CSVWriter

public CSVWriter(OutputStream out)

Constructor for writing into a stream.

Parameters:

out - output stream

CSVWriter

public CSVWriter(Writer out)

Deprecated. Use CSVWriter(OutputStream) instead.

For backwards compatibility only.

Parameters:

out - out writer

CSVWriter

public CSVWriter(Writer out,
                 boolean flush)

Deprecated.

For backwards compatibility only.

Parameters:

out - out writer

flush - has no influence and is for compatibility reasons only

CSVWriter

public CSVWriter(String file)
          throws IOException

Constructor for writing into a file.

Parameters:

file - file

Throws:

IOException - when an exception occurs

Method Detail

init

protected void init()

Initializes the writer.

Overrides:

init in class AbstractTableWriter

See Also:

AbstractTableWriter.init()

getWriter

public PrintWriter getWriter()

Returns the underlying stream.

Overrides:

getWriter in class AbstractStreamTableWriter

Returns:

the writer object

See Also:

AbstractStreamTableWriter.getWriter()

close

public void close()

Closes the underlying stream.

Specified by:

close in interface TableWriter

Overrides:

close in class AbstractStreamTableWriter

See Also:

AbstractStreamTableWriter.close()

setColumnDelimiter

public void setColumnDelimiter(String s)

Sets the column delimiter to be used. Default are double-quotes. The usage of the delimiters is defined by isColumnDelimiterRequired().

Parameters:

s - the new delimiter

getColumnDelimiter

public String getColumnDelimiter()

Returns the column delimiter to be used. Default are double-quotes.

Returns:

the column delimiter being used.

setColumnSeparator

public void setColumnSeparator(char s)

Sets the column separator to be used. Default is semi-colon.

Parameters:

s - new separator character

getColumnSeparator

public char getColumnSeparator()

Returns the column separator to be used. Default is semi-colon.

Returns:

the column separator character being used

setRowSeparator

public void setRowSeparator(String s)

Sets the row separator to be used. Actually you should never change this character as it will break the definition of a CSV stream. Default is newline character.

Parameters:

s - new separator

getRowSeparator

public String getRowSeparator()

Returns the row separator to be used. Default is a newline character.

Returns:

the row separator character.

setColumnDelimiterRequired

public void setColumnDelimiterRequired(boolean b)

Sets if column separators are always required or not. Usually, column delimiters are written only when the column value contains special characters, such as the delimiters for columns and rows. Default value is false.

Parameters:

b - true when delimiters shall always be written.

isColumnDelimiterRequired

public boolean isColumnDelimiterRequired()

Returns whether column delimiters are always required. Default value is false.

Returns:

true if column delimiters are written on each column.

getCommentChar

public char getCommentChar()

Returns the character used for indicating comments

Returns:

the commentChar

setCommentChar

public void setCommentChar(char commentChar)

Sets the character to be used for indicating comments

Parameters:

commentChar - the commentChar to set

prepareRow

public String prepareRow(Object[] columns)

Formats a row for CSV output.

Parameters:

columns - columns to be prepared

Returns:

string ready to be printed in CSV

printRow

public void printRow(Object[] columns)
              throws IOException

Prints a new row into the CSV file. This is the method where an actual CSV row will be printed. The columns are prepared to follow the CSV syntax rules and definitions. The underlying stream in flushed immediately.

Parameters:

columns - array of column values.

Throws:

IOException - when an exception occurs

prepareComment

public String prepareComment(String comment)

Formats a comment for printing

Parameters:

comment - comment to be printed

Returns:

string ready to be written to CSV

printComment

public void printComment(String comment)
                  throws IOException

Prints a comment into the CSV stream.

Specified by:

printComment in interface TableWriter

Overrides:

printComment in class AbstractTableWriter

Parameters:

comment - comment to write

Throws:

IOException - when an exception occurs

printComment

public void printComment(String comment,
                         int row,
                         int column)
                  throws IOException

Prints a comment into the stream. Note that not all implementations support comments.

Specified by:

printComment in interface TableWriter

Overrides:

printComment in class AbstractTableWriter

Parameters:

comment - comment to write

row - index of row for comment

column - index of column for comment

Throws:

IOException - when an exception occurs

columnNeedsDelimiting

protected boolean columnNeedsDelimiting(String s)

Decides if a column value needs to be wrapped with delimiters.

Parameters:

s - column value to check

Returns:

true if value must be wrapped in output

prepareColumnValue

protected String prepareColumnValue(String s)

Replaces all occurrences of the delimiter by doubling it.

Parameters:

s - column value to parse

Returns:

value with replaced delimiters.

getColumnCount

public int getColumnCount()

Returns the columns written to the stream.

Returns:

the columnCount