| /* |
| [The "BSD licence"] |
| Copyright (c) 2005-2008 Terence Parr |
| All rights reserved. |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| 1. Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| 2. Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| 3. The name of the author may not be used to endorse or promote products |
| derived from this software without specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| package org.eclipse.persistence.internal.libraries.antlr.runtime; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** A pretty quick CharStream that pulls all data from an array |
| * directly. Every method call counts in the lexer. Java's |
| * strings aren't very good so I'm avoiding. |
| */ |
| public class ANTLRStringStream implements CharStream { |
| /** The data being scanned */ |
| protected char[] data; |
| |
| /** How many characters are actually in the buffer */ |
| protected int n; |
| |
| /** 0..n-1 index into string of next char */ |
| protected int p=0; |
| |
| /** line number 1..n within the input */ |
| protected int line = 1; |
| |
| /** The index of the character relative to the beginning of the line 0..n-1 */ |
| protected int charPositionInLine = 0; |
| |
| /** tracks how deep mark() calls are nested */ |
| protected int markDepth = 0; |
| |
| /** A list of CharStreamState objects that tracks the stream state |
| * values line, charPositionInLine, and p that can change as you |
| * move through the input stream. Indexed from 1..markDepth. |
| * A null is kept @ index 0. Create upon first call to mark(). |
| */ |
| protected List markers; |
| |
| /** Track the last mark() call result value for use in rewind(). */ |
| protected int lastMarker; |
| |
| /** What is name or source of this char stream? */ |
| public String name; |
| |
| public ANTLRStringStream() { |
| } |
| |
| /** Copy data in string to a local char array */ |
| public ANTLRStringStream(String input) { |
| this(); |
| this.data = input.toCharArray(); |
| this.n = input.length(); |
| } |
| |
| /** This is the preferred constructor as no data is copied */ |
| public ANTLRStringStream(char[] data, int numberOfActualCharsInArray) { |
| this(); |
| this.data = data; |
| this.n = numberOfActualCharsInArray; |
| } |
| |
| /** Reset the stream so that it's in the same state it was |
| * when the object was created *except* the data array is not |
| * touched. |
| */ |
| public void reset() { |
| p = 0; |
| line = 1; |
| charPositionInLine = 0; |
| markDepth = 0; |
| } |
| |
| public void consume() { |
| //System.out.println("prev p="+p+", c="+(char)data[p]); |
| if ( p < n ) { |
| charPositionInLine++; |
| if ( data[p]=='\n' ) { |
| /* |
| System.out.println("newline char found on line: "+line+ |
| "@ pos="+charPositionInLine); |
| */ |
| line++; |
| charPositionInLine=0; |
| } |
| p++; |
| //System.out.println("p moves to "+p+" (c='"+(char)data[p]+"')"); |
| } |
| } |
| |
| public int LA(int i) { |
| if ( i==0 ) { |
| return 0; // undefined |
| } |
| if ( i<0 ) { |
| i++; // e.g., translate LA(-1) to use offset i=0; then data[p+0-1] |
| if ( (p+i-1) < 0 ) { |
| return CharStream.EOF; // invalid; no char before first char |
| } |
| } |
| |
| if ( (p+i-1) >= n ) { |
| //System.out.println("char LA("+i+")=EOF; p="+p); |
| return CharStream.EOF; |
| } |
| //System.out.println("char LA("+i+")="+(char)data[p+i-1]+"; p="+p); |
| //System.out.println("LA("+i+"); p="+p+" n="+n+" data.length="+data.length); |
| return data[p+i-1]; |
| } |
| |
| public int LT(int i) { |
| return LA(i); |
| } |
| |
| /** Return the current input symbol index 0..n where n indicates the |
| * last symbol has been read. The index is the index of char to |
| * be returned from LA(1). |
| */ |
| public int index() { |
| return p; |
| } |
| |
| public int size() { |
| return n; |
| } |
| |
| public int mark() { |
| if ( markers==null ) { |
| markers = new ArrayList(); |
| markers.add(null); // depth 0 means no backtracking, leave blank |
| } |
| markDepth++; |
| CharStreamState state = null; |
| if ( markDepth>=markers.size() ) { |
| state = new CharStreamState(); |
| markers.add(state); |
| } |
| else { |
| state = (CharStreamState)markers.get(markDepth); |
| } |
| state.p = p; |
| state.line = line; |
| state.charPositionInLine = charPositionInLine; |
| lastMarker = markDepth; |
| return markDepth; |
| } |
| |
| public void rewind(int m) { |
| CharStreamState state = (CharStreamState)markers.get(m); |
| // restore stream state |
| seek(state.p); |
| line = state.line; |
| charPositionInLine = state.charPositionInLine; |
| release(m); |
| } |
| |
| public void rewind() { |
| rewind(lastMarker); |
| } |
| |
| public void release(int marker) { |
| // unwind any other markers made after m and release m |
| markDepth = marker; |
| // release this marker |
| markDepth--; |
| } |
| |
| /** consume() ahead until p==index; can't just set p=index as we must |
| * update line and charPositionInLine. |
| */ |
| public void seek(int index) { |
| if ( index<=p ) { |
| p = index; // just jump; don't update stream state (line, ...) |
| return; |
| } |
| // seek forward, consume until p hits index |
| while ( p<index ) { |
| consume(); |
| } |
| } |
| |
| public String substring(int start, int stop) { |
| return new String(data,start,stop-start+1); |
| } |
| |
| public int getLine() { |
| return line; |
| } |
| |
| public int getCharPositionInLine() { |
| return charPositionInLine; |
| } |
| |
| public void setLine(int line) { |
| this.line = line; |
| } |
| |
| public void setCharPositionInLine(int pos) { |
| this.charPositionInLine = pos; |
| } |
| |
| public String getSourceName() { |
| return name; |
| } |
| } |