javolution.text
Class Cursor

java.lang.Object
  java.text.ParsePosition
      javolution.text.Cursor

All Implemented Interfaces:

Reusable

public class Cursor
extends java.text.ParsePosition
implements Reusable

This class represents a parsing cursor over characters. Cursor allows for token iterations over any CharSequence.

       CharSequence csq = "this is a test";
       for (Cursor cursor = new Cursor(); cursor.skip(CharSet.WHITESPACES, csq);) {
           System.out.println(cursor.nextToken(csq, CharSet.WHITESPACES));
       }

Prints the following output:

        this
        is
        a
        test

Cursors are typically used with TextFormat instances.

        public Font parse(CharSequence csq, Cursor cursor) {
            CharSequence fontName = cursor.nextToken(csq, CharSet.WHITESPACE);
            return Font.decode(fontName.toString());
        }

Version:

5.3, February 15, 2006

Author:

Jean-Marie Dautelle

Constructor Summary

Cursor()
Default constructor.

Method Summary

boolean	equals(java.lang.Object obj) Indicates if this cursor is equals to the specified object.
int	getIndex() Returns this cursor index.
int	hashCode() Returns the hash code for this cursor.
boolean	hasNext(java.lang.CharSequence csq) Indicates if this cursor points to a valid character in the specified character sequence.
Cursor	increment() Increments the cursor index by one.
Cursor	increment(int i) Increments the cursor index by the specified value.
char	next(java.lang.CharSequence csq) Returns the next character at this cursor position.
java.lang.CharSequence	nextToken(java.lang.CharSequence csq, char c) Returns the subsequence from the specified cursor position not holding the specified character.
java.lang.CharSequence	nextToken(java.lang.CharSequence csq, CharSet charSet) Returns the subsequence from the specified cursor position not holding any of the characters specified.
void	reset() Resets this cursor instance.
void	setIndex(int i) Sets the cursor current index.
boolean	skip(char c, java.lang.CharSequence csq) Moves this cursor forward until it points to a character different from the specified character.
boolean	skip(CharSet charSet, java.lang.CharSequence csq) Moves this cursor forward until it points to a character different from any of the character in the specified set.
java.lang.String	toString() Returns the string representation of this cursor.

Methods inherited from class java.text.ParsePosition

getErrorIndex, setErrorIndex

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Cursor

public Cursor()

Default constructor.

Method Detail

getIndex

public final int getIndex()

Returns this cursor index.

Overrides:

getIndex in class java.text.ParsePosition

Returns:

the index of the next character to parse.

setIndex

public void setIndex(int i)

Sets the cursor current index.

Overrides:

setIndex in class java.text.ParsePosition

Parameters:

i - the index of the next character to parse.

hasNext

public final boolean hasNext(java.lang.CharSequence csq)

Indicates if this cursor points to a valid character in the specified character sequence.

Parameters:

csq - the character sequence iterated by this cursor.

Returns:

true if this cursor points to a valid character position; false otherwise.

next

public final char next(java.lang.CharSequence csq)

Returns the next character at this cursor position. The cursor position is incremented by one.

Parameters:

csq - the character sequence iterated by this cursor.

Returns:

this cursor points to a valid character; false otherwise.

Throws:

java.lang.IndexOutOfBoundsException - if !hasNext(csq)

skip

public final boolean skip(char c,
                          java.lang.CharSequence csq)

Moves this cursor forward until it points to a character different from the specified character.

Parameters:

c - the character to skip.

csq - the character sequence iterated by this cursor.

Returns:

true if this cursor points to a character different from the ones specified; false otherwise (end of sequence reached).

skip

public final boolean skip(CharSet charSet,
                          java.lang.CharSequence csq)

Moves this cursor forward until it points to a character different from any of the character in the specified set. For example:

  // Reads numbers separated by tabulations or spaces.
  FastTable<Integer> numbers = new FastTable<Integer>();
  while (cursor.skip(CharSet.SPACE_OR_TAB, csq)) {
      numbers.add(TypeFormat.parseInt(csq, cursor));
  }

Parameters:

charSet - the character to skip.

csq - the character sequence iterated by this cursor.

Returns:

true if this cursor points to a character different from the ones specified; false otherwise (e.g. end of sequence reached).

nextToken

public final java.lang.CharSequence nextToken(java.lang.CharSequence csq,
                                              char c)

Returns the subsequence from the specified cursor position not holding the specified character. For example:

    CharSequence csq = "This is a test";
    for (CharSequence token; (token=cursor.nextToken(csq, ' '))!= null;) {
        System.out.println(token); // Prints one word at a time.
    }

Parameters:

csq - the character sequence iterated by this cursor.

c - the character being skipped.

Returns:

the subsequence not holding the specified character or null if none.

nextToken

public final java.lang.CharSequence nextToken(java.lang.CharSequence csq,
                                              CharSet charSet)

Returns the subsequence from the specified cursor position not holding any of the characters specified. For example:

    CharSequence csq = "This is a test";
    for (CharSequence token; (token=cursor.nextToken(csq, CharSet.WHITESPACE))!= null;) {
        System.out.println(token); // Prints one word at a time.
    }

Parameters:

csq - the character sequence iterated by this cursor.

charSet - the characters being skipped.

Returns:

the subsequence not holding the specified character or null if none.

increment

public final Cursor increment()

Increments the cursor index by one.

Returns:

this

increment

public final Cursor increment(int i)

Increments the cursor index by the specified value.

Parameters:

i - the increment value.

Returns:

this

toString

public java.lang.String toString()

Returns the string representation of this cursor.

Overrides:

toString in class java.text.ParsePosition

Returns:

the index value as a string.

equals

public boolean equals(java.lang.Object obj)

Indicates if this cursor is equals to the specified object.

Overrides:

equals in class java.text.ParsePosition

Returns:

true if the specified object is a cursor at the same index; false otherwise.

hashCode

public int hashCode()

Returns the hash code for this cursor.

Overrides:

hashCode in class java.text.ParsePosition

Returns:

the hash code value for this object

reset

public void reset()

Resets this cursor instance.

Specified by:

reset in interface Reusable

See Also:

Reusable