com.meyling.principia.io
Class Input

java.lang.Object
  |
  +--com.meyling.principia.io.Input

public class Input

extends Object

This class provides convenient methods for parsing input. TODO offer input stream constructor

Version:

$Revision 0.00.50$

Author:

Michael Meyling

Field Summary

private static char	CR char marking end of input line
private static char	EOF char marking end of data
private StringBuffer	line current line
private int	lineNumber current line number
private static String	MARKER string for marking current reading position
private int	position current reading position
private StringBuffer	source holds the data

Constructor Summary

Input(String source)
Constructor using String source.

Input(StringBuffer source)
Constructor using StringBuffer source.

Method Summary

char	getChar() Reads a single character and does not change the reading position.
char	getChar(int i) Reads a single character and does not change the reading position.
int	getLineNumber() Returns the current line number.
boolean	isEmpty() Is there no data left for reading?
char	readChar() Reads a single character and increments the reading position by one.
int	readCounter() Reads the next positive integer made completly out of digits, leading whitespace is skipped.
String	readLetterDigitString() Reads the next string containing only letters or digits, leading whitespace is skipped.
String	readQuoted() Reads the next quoted string, leading whitespace is skipped.
String	showLinePosition() Show reading position.
void	skipWhiteSpace() Skips white space, beginning from reading position.

Methods inherited from class java.lang.Object

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

Field Detail

EOF

private static final char EOF

char marking end of data

CR

private static final char CR

char marking end of input line

MARKER

private static final String MARKER

string for marking current reading position

source

private final StringBuffer source

holds the data

line

private StringBuffer line

current line

lineNumber

private int lineNumber

current line number

position

private int position

current reading position

Constructor Detail

Input

public Input(StringBuffer source)

Constructor using StringBuffer source.

Parameters:

source - data source

Throws:

IllegalArgumentException - if argument was an nullpointer

Input

public Input(String source)

Constructor using String source.

Parameters:

source - data source

Throws:

IllegalArgumentException - if argument was an nullpointer

Method Detail

readChar

public final char readChar()

Reads a single character and increments the reading position by one.

Returns:

character read, if there are no more chars Character.MAX_VALUE is returned

getChar

public final char getChar()

Reads a single character and does not change the reading position.

Returns:

character read, if there are no more chars Character.MAX_VALUE is returned

getChar

public final char getChar(int i)

Reads a single character and does not change the reading position.

Parameters:

i - offset from current reading position.

Returns:

character read, if there are no more chars Character.MAX_VALUE is returned

getLineNumber

public final int getLineNumber()

Returns the current line number.

Returns:

current line number

skipWhiteSpace

public final void skipWhiteSpace()

Skips white space, beginning from reading position. Changes reading position to next non white space character.

isEmpty

public final boolean isEmpty()

Is there no data left for reading?

Returns:

is all data read?

readLetterDigitString

public final String readLetterDigitString()

Reads the next string containing only letters or digits, leading whitespace is skipped. Changes reading position.

Returns:

read string

Throws:

IllegalArgumentException - if no such characters could be found

readCounter

public final int readCounter()

Reads the next positive integer made completly out of digits, leading whitespace is skipped. Changes reading position.

Returns:

read integer

Throws:

IllegalArgumentException - if no digits where found or the number was to big for an int

readQuoted

public final String readQuoted()
                        throws IllegalArgumentException

Reads the next quoted string, leading whitespace is skipped. A correctly quoted string could be created by adding a leading and a trailing quote character and doubling each other quote character. The resulting string is dequoted. Changes reading position.

Returns:

deqoted read string

Throws:

IllegalArgumentException - if no correctly quoted string was found

showLinePosition

public final String showLinePosition()

Show reading position.

Returns:

current line with mark at current reading position