org.esa.beam.util.io
Class CsvReader

java.lang.Object
  java.io.Reader
      java.io.BufferedReader
          java.io.LineNumberReader
              org.esa.beam.util.io.CsvReader

All Implemented Interfaces:

Closeable, Readable

public class CsvReader
extends LineNumberReader

A CsvReader instance is used read text files with CSV (comma separated values) format.

This reader interprets each line of a text file as record (also empty lines). The fields of the record are delimited by a single separator character which must not necessarily be a comma.

Version:

1.1

Author:

Norman Fomferra

Field Summary

Fields inherited from class java.io.Reader

lock

Constructor Summary

CsvReader(Reader reader, char[] separators)
Constructs a CSV reader using the given column separator characters.

CsvReader(Reader reader, char[] separators, boolean ignoreEmptyLines, String commentPrefix)
Constructs a CSV reader using the given column separator characters and the format properties.

Method Summary

String	getCommentPrefix() Gets the comment prefix string (if any).
char[]	getSeparators()
boolean	ignoresEmptyLines()
double[]	readDoubleRecord()
List<double[]>	readDoubleRecords()
String[]	readRecord() Reads a record info from the database.
List<String[]>	readStringRecords() Reads the complete file from the current position on.

Methods inherited from class java.io.LineNumberReader

getLineNumber, mark, read, read, readLine, reset, setLineNumber, skip

Methods inherited from class java.io.BufferedReader

close, markSupported, ready

Methods inherited from class java.io.Reader

read, read

Methods inherited from class java.lang.Object

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

Constructor Detail

CsvReader

public CsvReader(Reader reader,
                 char[] separators)

Constructs a CSV reader using the given column separator characters. The new reader will not ignore empty lines and does not recognize comment lines.

Parameters:

reader - the underlying reader to be wrapped

separators - the column separator characters

CsvReader

public CsvReader(Reader reader,
                 char[] separators,
                 boolean ignoreEmptyLines,
                 String commentPrefix)

Constructs a CSV reader using the given column separator characters and the format properties.

Parameters:

reader - the underlying reader to be wrapped

separators - the column separator characters

ignoreEmptyLines - if true, empty lines are ignored

commentPrefix - if not null, the prefix string for comment lines

Method Detail

getSeparators

public final char[] getSeparators()

Returns:

The column separator characters.

ignoresEmptyLines

public final boolean ignoresEmptyLines()

Returns:

Are empty lines ignored?

getCommentPrefix

public final String getCommentPrefix()

Gets the comment prefix string (if any).

Returns:

The comment prefix string, if any. null otherwise.

readRecord

public String[] readRecord()
                    throws IOException

Reads a record info from the database. A record is represented by a complete line in the CSV formatted text file.

Leading and trailing whitespaces removed from each column value. For empty lines, the method returns an array of the length zero. The method returns null if the end of file has been reached.

Returns:

a record containing the tokens delimited by the separator character passed to the constructor

Throws:

IOException - if an I/O error occurs

readDoubleRecord

public double[] readDoubleRecord()
                          throws IOException

Throws:

IOException

readStringRecords

public List<String[]> readStringRecords()
                                 throws IOException

Reads the complete file from the current position on. If the readLineRecord has not previously been called the method reads all records from the beginning of the file. For empty files, the method returns an vector having a zero size.

Returns:

an vector of String[] records containing the tokens delimitted by the separator character passed to the constructor

Throws:

IOException - if an I/O error occurs

readDoubleRecords

public List<double[]> readDoubleRecords()
                                 throws IOException

Throws:

IOException