net.thevpc.nuts.runtime.standalone.util

Class DefaultNTextCursorTracker

java.lang.Object

net.thevpc.nuts.runtime.standalone.util.DefaultNTextCursorTracker

All Implemented Interfaces:

NTextCursorTracker

public final class DefaultNTextCursorTracker
extends Object
implements NTextCursorTracker

Tracks line/column position with bounded rewind capability. Optimized for code generation: minimal memory, fail-fast semantics.

Memory footprint: 1 bit per rewindable special char (maxRewindDepth). Example: maxRewindDepth=1024 → ~128 bytes history buffer.

Constructor Summary

Constructors

Constructor and Description
DefaultNTextCursorTracker() Creates cursor with unlimited rewind depth (use cautiously for huge files).
DefaultNTextCursorTracker(int tabSize, int maxRewindDepth) Creates cursor with bounded rewind depth.

Method Summary

Modifier and Type	Method and Description
void	clearHistory() Discards all rewind history.
void	consume(char c)
void	consume(char[] buffer, int offset, int len)
void	consume(String s)
int	line()
int	maxRewindDepth() Returns maximum configured rewind depth (0 = unlimited).
int	physicalColumn()
void	reset()
void	rewind(char c) Rewinds the effect of consuming c.
int	rewindDepth() Returns current rewind depth (number of operations that can be rewound).
int	visualColumn()

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.thevpc.nuts.io.NTextCursorTracker

of, of

Constructor Detail

DefaultNTextCursorTracker

public DefaultNTextCursorTracker()

Creates cursor with unlimited rewind depth (use cautiously for huge files).

DefaultNTextCursorTracker

public DefaultNTextCursorTracker(int tabSize,
                                 int maxRewindDepth)

Creates cursor with bounded rewind depth.

Parameters:

tabSize - number of visual columns per tab stop (>0)

maxRewindDepth - maximum number of rewindable operations (0 = unlimited)

Method Detail

consume

public void consume(char c)

Specified by:

consume in interface NTextCursorTracker

consume

public void consume(String s)

Specified by:

consume in interface NTextCursorTracker

consume

public void consume(char[] buffer,
                    int offset,
                    int len)

Specified by:

consume in interface NTextCursorTracker

rewind

public void rewind(char c)

Rewinds the effect of consuming c. MUST be called in strict reverse (LIFO) order of consumption.

Specified by:

rewind in interface NTextCursorTracker

Throws:

IllegalStateException - if insufficient history exists to rewind

clearHistory

public void clearHistory()

Discards all rewind history. Use after reaching a stable generation point where you know you won't rewind beyond this position.

Example pattern: cursor.consume("public class Foo {\n"); cursor.clearHistory(); // Won't rewind past class declaration // ... generate method bodies with conditional rewinds ...

Specified by:

clearHistory in interface NTextCursorTracker

rewindDepth

public int rewindDepth()

Returns current rewind depth (number of operations that can be rewound).

Specified by:

rewindDepth in interface NTextCursorTracker

maxRewindDepth

public int maxRewindDepth()

Returns maximum configured rewind depth (0 = unlimited).

Specified by:

maxRewindDepth in interface NTextCursorTracker

line

public int line()

Specified by:

line in interface NTextCursorTracker

physicalColumn

public int physicalColumn()

Specified by:

physicalColumn in interface NTextCursorTracker

visualColumn

public int visualColumn()

Specified by:

visualColumn in interface NTextCursorTracker

reset

public void reset()

Specified by:

reset in interface NTextCursorTracker