com.sun.tools.javac.util
Class Position

java.lang.Object
  com.sun.tools.javac.util.Position

public class Position
extends java.lang.Object

A class that defines source code positions as simple character offsets from the beginning of the file. The first character is at position 0. Support is also provided for (line,column) coordinates, but tab expansion is optional and no Unicode excape translation is considered. The first character is at location (1,1).

This is NOT part of any API supported by Sun Microsystems. If you write code that depends on this, you do so at your own risk. This code and its internal interfaces are subject to change or deletion without notice.

Nested Class Summary

static interface	Position.LineMap
(package private) static class	Position.LineMapImpl
static class	Position.LineTabMapImpl A LineMap that handles tab expansion correctly.

Field Summary

static int	FIRSTCOLUMN
static int	FIRSTLINE
static int	FIRSTPOS
static int	LINESHIFT
static int	MAXCOLUMN
static int	MAXLINE
static int	MAXPOS
static int	NOPOS

Constructor Summary

private

Position() This is class is not supposed to be instantiated.

Method Summary

static int	encodePosition(int line, int col) Encode line and column numbers in an integer as: line-number << LINESHIFT + column-number {@link Position.NOPOS represents an undefined position.
static Position.LineMap	makeLineMap(char[] src, int max, boolean expandTabs) A two-way map between line/column numbers and positions, derived from a scan done at creation time.

Methods inherited from class java.lang.Object

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

Field Detail

NOPOS

public static final int NOPOS

See Also:

Constant Field Values

FIRSTPOS

public static final int FIRSTPOS

See Also:

Constant Field Values

FIRSTLINE

public static final int FIRSTLINE

See Also:

Constant Field Values

FIRSTCOLUMN

public static final int FIRSTCOLUMN

See Also:

Constant Field Values

LINESHIFT

public static final int LINESHIFT

See Also:

Constant Field Values

MAXCOLUMN

public static final int MAXCOLUMN

See Also:

Constant Field Values

MAXLINE

public static final int MAXLINE

See Also:

Constant Field Values

MAXPOS

public static final int MAXPOS

See Also:

Constant Field Values

Constructor Detail

Position

private Position()

This is class is not supposed to be instantiated.

Method Detail

makeLineMap

public static Position.LineMap makeLineMap(char[] src,
                                           int max,
                                           boolean expandTabs)

A two-way map between line/column numbers and positions, derived from a scan done at creation time. Tab expansion is optionally supported via a character map. Text content is not retained.

Notes: The first character position FIRSTPOS is at (FIRSTLINE,FIRSTCOLUMN). No account is taken of Unicode escapes.

Parameters:

src - Source characters

max - Number of characters to read

expandTabs - If true, expand tabs when calculating columns

encodePosition

public static int encodePosition(int line,
                                 int col)

Encode line and column numbers in an integer as: line-number << LINESHIFT + column-number {@link Position.NOPOS represents an undefined position.

Parameters:

line - number of line (first is 1)

col - number of character on line (first is 1)

Returns:

an encoded position or {@link Position.NOPOS if the line or column number is too big to represent in the encoded format

Throws:

java.lang.IllegalArgumentException - if line or col is less than 1