com.Ostermiller.util

Class ExcelCSVParser

java.lang.Object

com.Ostermiller.util.ExcelCSVParser

All Implemented Interfaces:

CSVParse

public class ExcelCSVParser
extends java.lang.Object
implements CSVParse

Read files in comma separated value format as outputted by the Microsoft Excel Spreadsheet program. More information about this class is available from ostermiller.org.

Excel CSV is a file format used as a portable representation of a database. Each line is one entry or record and the fields in a record are separated by commas.

If field includes a comma or a new line, the whole field must be surrounded with double quotes. When the field is in quotes, any quote literals must be escaped by two quotes (""). Text that comes after quotes that have been closed but come before the next comma will be ignored.

Empty fields are returned as as String of length zero: "". The following line has three empty fields and three non-empty fields in it. There is an empty field on each end, and one in the middle. One token is returned as a space.

,second,, ,fifth,

Blank lines are always ignored. Other lines will be ignored if they start with a comment character as set by the setCommentStart() method.

An example of how CVSLexer might be used:

 ExcelCSVParser shredder = new ExcelCSVParser(System.in);
 String t;
 while ((t = shredder.nextValue()) != null){
     System.out.println("" + shredder.lastLineNumber() + " " + t);
 }
 

The CSV that Excel outputs differs from the standard in several respects:

• Leading and trailing whitespace is significant.
• A backslash is not a special character and is not used to escape anything.
• Quotes inside quoted strings are escaped with a double quote rather than a backslash.
• Excel may convert data before putting it in CSV format:
  • Tabs are converted to a single space.
  • New lines in the data are always represented as the UNIX new line. ("\n")
  • Numbers that are greater than 12 digits may be represented in truncated scientific notation form.
  This parser does not attempt to fix these excel conversions, but users should be aware of them.

Since:

ostermillerutils 1.00.00

See Also:

CSVParser

Constructor Summary

Constructors

Constructor and Description
ExcelCSVParser(java.io.InputStream in) Create a parser to parse comma separated values from an InputStream.
ExcelCSVParser(java.io.InputStream in, char delimiter) Create a parser to parse delimited values from an InputStream.
ExcelCSVParser(java.io.Reader in) Create a parser to parse comma separated values from a Reader.
ExcelCSVParser(java.io.Reader in, char delimiter) Create a parser to parse delimited values from a Reader.

Method Summary

Modifier and Type	Method and Description
void	changeDelimiter(char newDelim) Change this parser so that it uses a new delimiter.
void	changeQuote(char newQuote) Change this parser so that it uses a new character for quoting.
void	close() Close any stream upon which this parser is based.
java.lang.String[][]	getAllValues() Get all the values from the file.
int	getLastLineNumber() Get the number of the line from which the last value was retrieved.
java.lang.String[]	getLine() Get all the values from a line.
int	lastLineNumber() Get the line number that the last token came from.
java.lang.String	nextValue() get the next value.
static java.lang.String[][]	parse(java.io.Reader in) Parse the comma delimited data from a stream.
static java.lang.String[][]	parse(java.io.Reader in, char delimiter) Parse the delimited data from a stream.
static java.lang.String[][]	parse(java.lang.String s) Parse the comma delimited data from a string.
static java.lang.String[][]	parse(java.lang.String s, char delimiter) Parse the delimited data from a string.
void	setCommentStart(java.lang.String commentDelims) Set the characters that indicate a comment at the beginning of the line.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExcelCSVParser

public ExcelCSVParser(java.io.InputStream in,
                      char delimiter)
               throws BadDelimiterException

Create a parser to parse delimited values from an InputStream.

Parameters:

in - stream that contains comma separated values.

delimiter - record separator

Throws:

BadDelimiterException - if the specified delimiter cannot be used

Since:

ostermillerutils 1.02.24

ExcelCSVParser

public ExcelCSVParser(java.io.InputStream in)

Create a parser to parse comma separated values from an InputStream.

Parameters:

in - stream that contains comma separated values.

Since:

ostermillerutils 1.00.00

ExcelCSVParser

public ExcelCSVParser(java.io.Reader in,
                      char delimiter)
               throws BadDelimiterException

Create a parser to parse delimited values from a Reader.

Parameters:

in - reader that contains comma separated values.

delimiter - record separator

Throws:

BadDelimiterException - if the specified delimiter cannot be used

Since:

ostermillerutils 1.02.24

ExcelCSVParser

public ExcelCSVParser(java.io.Reader in)

Create a parser to parse comma separated values from a Reader.

Parameters:

in - reader that contains comma separated values.

Since:

ostermillerutils 1.00.00

Method Detail

close

public void close()
           throws java.io.IOException

Close any stream upon which this parser is based.

Specified by:

close in interface CSVParse

Throws:

java.io.IOException - if an error occurs while closing the stream.

Since:

ostermillerutils 1.02.22

nextValue

public java.lang.String nextValue()
                           throws java.io.IOException

get the next value.

Specified by:

nextValue in interface CSVParse

Returns:

the next value or null if there are no more values.

Throws:

java.io.IOException - if an error occurs while reading.

Since:

ostermillerutils 1.00.00

lastLineNumber

public int lastLineNumber()

Get the line number that the last token came from.

New line breaks that occur in the middle of a token are no counted in the line number count.

Specified by:

lastLineNumber in interface CSVParse

Returns:

line number or -1 if no tokens have been returned yet.

Since:

ostermillerutils 1.00.00

getLine

public java.lang.String[] getLine()
                           throws java.io.IOException

Get all the values from a line.

If the line has already been partially read, only the values that have not already been read will be included.

Specified by:

getLine in interface CSVParse

Returns:

all the values from the line or null if there are no more values.

Throws:

java.io.IOException - if an error occurs while reading.

Since:

ostermillerutils 1.00.00

getAllValues

public java.lang.String[][] getAllValues()
                                  throws java.io.IOException

Get all the values from the file.

If the file has already been partially read, only the values that have not already been read will be included.

Each line of the file that has at least one value will be represented. Comments and empty lines are ignored.

The resulting double array may be jagged.

Specified by:

getAllValues in interface CSVParse

Returns:

all the values from the file or null if there are no more values.

Throws:

java.io.IOException - if an error occurs while reading.

Since:

ostermillerutils 1.00.00

changeDelimiter

public void changeDelimiter(char newDelim)
                     throws BadDelimiterException

Change this parser so that it uses a new delimiter.

The initial character is a comma, the delimiter cannot be changed to a quote or other character that has special meaning in CSV.

Specified by:

changeDelimiter in interface CSVParse

Parameters:

newDelim - delimiter to which to switch.

Throws:

BadDelimiterException - if the character cannot be used as a delimiter.

Since:

ostermillerutils 1.02.08

changeQuote

public void changeQuote(char newQuote)
                 throws BadQuoteException

Change this parser so that it uses a new character for quoting.

The initial character is a double quote ("), the delimiter cannot be changed to a comma or other character that has special meaning in CSV.

Specified by:

changeQuote in interface CSVParse

Parameters:

newQuote - character to use for quoting.

Throws:

BadQuoteException - if the character cannot be used as a quote.

Since:

ostermillerutils 1.02.16

setCommentStart

public void setCommentStart(java.lang.String commentDelims)

Set the characters that indicate a comment at the beginning of the line. For example if the string "#;!" were passed in, all of the following lines would be comments:

 # Comment
 ; Another Comment
 ! Yet another comment

By default there are no comments in CVS files. Commas and quotes may not be used to indicate comment lines.

Parameters:

commentDelims - list of characters a comment line may start with.

Since:

ostermillerutils 1.00.00

getLastLineNumber

public int getLastLineNumber()

Get the number of the line from which the last value was retrieved.

Specified by:

getLastLineNumber in interface CSVParse

Returns:

line number or -1 if no tokens have been returned.

Since:

ostermillerutils 1.00.00

parse

public static java.lang.String[][] parse(java.lang.String s)

Parse the comma delimited data from a string.

Parameters:

s - string with comma delimited data to parse.

Returns:

parsed data.

Since:

ostermillerutils 1.02.03

parse

public static java.lang.String[][] parse(java.lang.String s,
                                         char delimiter)
                                  throws BadDelimiterException

Parse the delimited data from a string.

Parameters:

s - string with delimited data to parse.

delimiter - record separator

Returns:

parsed data.

Throws:

BadDelimiterException - if the character cannot be used as a delimiter.

Since:

ostermillerutils 1.02.24

parse

public static java.lang.String[][] parse(java.io.Reader in)
                                  throws java.io.IOException

Parse the comma delimited data from a stream.

Parameters:

in - Reader with comma delimited data to parse.

Returns:

parsed data.

Throws:

java.io.IOException - if an error occurs while reading.

Since:

ostermillerutils 1.02.03

parse

public static java.lang.String[][] parse(java.io.Reader in,
                                         char delimiter)
                                  throws java.io.IOException,
                                         BadDelimiterException

Parse the delimited data from a stream.

Parameters:

in - Reader with delimited data to parse.

delimiter - record separator

Returns:

parsed data.

Throws:

BadDelimiterException - if the character cannot be used as a delimiter.

java.io.IOException - if an error occurs while reading.

Since:

ostermillerutils 1.02.24