de.rwth.utils
Class Table

java.lang.Object
  |
  +--de.rwth.utils.Table

public class Table

extends java.lang.Object

A class for creating tables consisting of rows and columns. Each column has a field name associated with it and each row has a key name associated with it. The resulting tables can be converted to a String which is suitable for CSV (comma separated values) files.

Version:

$Id: Table.java,v 1.3 2002/09/17 06:53:53 mohnen Exp $

Author:

Markus Mohnen

Field Summary

protected char	columnsep The column separator char for the conversion to String.
protected java.util.LinkedList	fieldnames The list of field names.
protected java.lang.String	keyname The field name of the key column.
protected java.util.HashMap	keys Stores the rows of the table.
protected char	quotechar The quote char for the conversion to String.
protected char	recordsep The record separator char for the conversion to String.

Constructor Summary

Table(java.lang.String keyname)
Creates a new Table instance with default values for record separator (\n), column separator (,), and quote character (").

Method Summary

void	addNewFieldName(java.lang.String fieldname) Creates a new column in this table.
void	createNewKey(java.lang.String key) Creates a new row in this table.
java.lang.Object	getFieldForKey(java.lang.String fieldname, java.lang.String key) Gets the value of a cell for a specific row/column.
boolean	hasFieldName(java.lang.String fieldname) Checks if a String is a valid field name in this table.
static void	main(java.lang.String[] args) Mini test environment.
protected java.lang.String	maybequote(java.lang.Object o) Returns the maybe quoted String representation of its argument.
void	setFieldForKey(java.lang.String fieldname, java.lang.String key, java.lang.Object value) Sets the value of a cell for a specific row/column.
java.lang.String	toString() Creates a String representation of this table.

Methods inherited from class java.lang.Object

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

Field Detail

keyname

protected java.lang.String keyname

The field name of the key column.

fieldnames

protected java.util.LinkedList fieldnames

The list of field names.

keys

protected java.util.HashMap keys

Stores the rows of the table. Each row hashes the key name of the row to a HashMap of column entries, which in turn hash a field name to the value in the cell.

recordsep

protected char recordsep

The record separator char for the conversion to String.

columnsep

protected char columnsep

The column separator char for the conversion to String.

quotechar

protected char quotechar

The quote char for the conversion to String.

Constructor Detail

Table

public Table(java.lang.String keyname)

Creates a new Table instance with default values for record separator (\n), column separator (,), and quote character (").

Parameters:

keyname - a String value with the name of the key column.

Method Detail

hasFieldName

public boolean hasFieldName(java.lang.String fieldname)

Checks if a String is a valid field name in this table.

Parameters:

fieldname - a String value: The name to check.

Returns:

a boolean value: true if and only if the name was the argument to the constructor of this table, or the argument of one of the subsequent calls to addNewFieldName.

addNewFieldName

public void addNewFieldName(java.lang.String fieldname)
                     throws java.lang.IllegalArgumentException

Creates a new column in this table.

Parameters:

fieldname - a String value

Throws:

java.lang.IllegalArgumentException - if the fieldname is already one of the field names or the name of the key column.

createNewKey

public void createNewKey(java.lang.String key)
                  throws java.lang.IllegalArgumentException

Creates a new row in this table.

Parameters:

key - a String value

Throws:

java.lang.IllegalArgumentException - if there is already a row with key.

setFieldForKey

public void setFieldForKey(java.lang.String fieldname,
                           java.lang.String key,
                           java.lang.Object value)
                    throws java.lang.IllegalArgumentException

Sets the value of a cell for a specific row/column.

Parameters:

fieldname - a String value: The column of the cell.

key - a String value: The row of the cell.

value - an Object value

Throws:

java.lang.IllegalArgumentException - if either row or column do not exist or if there is already a value for this cell.

getFieldForKey

public java.lang.Object getFieldForKey(java.lang.String fieldname,
                                       java.lang.String key)

Gets the value of a cell for a specific row/column.

Parameters:

fieldname - a String value: The column of the cell.

key - a String value: The row of the cell.

Returns:

an Object value: The value

Throws:

java.lang.IllegalArgumentException - if either row or column do not exist or if there is no value associated with this cell.

maybequote

protected java.lang.String maybequote(java.lang.Object o)

Returns the maybe quoted String representation of its argument.

Parameters:

o - an Object value

Returns:

a String value

toString

public java.lang.String toString()

Creates a String representation of this table. Rows are separated with the record separator and columns with a column separator. The first row contains the field names. In each row, the first entry is the key of the row, followed by string representations of the values obtained by toString(). The order of rows and keys is undetermined. If the string representation of a value contains the column separator or blanks at the beginning or end, it is enclosed in quotes and quotes inside are doubled.

Overrides:

toString in class java.lang.Object

Returns:

a String value

main

public static void main(java.lang.String[] args)

Mini test environment.

Parameters:

args - a String[] value