Package com.sun.tools.javac.util

Class Position

java.lang.Object

com.sun.tools.javac.util.Position

public class Position
extends 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 supported API. 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

Nested Classes

Modifier and Type	Class and Description
static interface	Position.LineMap
static class	Position.LineTabMapImpl A LineMap that handles tab expansion correctly.

Field Summary

Fields

Modifier and Type	Field and Description
static int	FIRSTCOLUMN
static int	FIRSTLINE
static int	FIRSTPOS
static int	LINESHIFT
static int	MAXCOLUMN
static int	MAXLINE
static int	MAXPOS
static int	NOPOS

Method Summary

Modifier and Type	Method and Description
static int	encodePosition(int line, int col) Encode line and column numbers in an integer as: line-number << LINESHIFT + column-number .
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

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Constant Field Values

FIRSTPOS

public static final int FIRSTPOS

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Constant Field Values

FIRSTLINE

public static final int FIRSTLINE

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Constant Field Values

FIRSTCOLUMN

public static final int FIRSTCOLUMN

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Constant Field Values

LINESHIFT

public static final int LINESHIFT

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Constant Field Values

MAXCOLUMN

public static final int MAXCOLUMN

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Constant Field Values

MAXLINE

public static final int MAXLINE

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Constant Field Values

MAXPOS

public static final int MAXPOS

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Constant Field Values

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 . 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 NOPOS if the line or column number is too big to represent in the encoded format

Throws:

IllegalArgumentException - if line or col is less than 1