package org.reldb.dbrowser.ui.content.cmd;
import java.io.IOException;
import java.io.StringReader;
import java.util.Hashtable;
import java.util.Vector;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.LineStyleEvent;
import org.eclipse.swt.custom.LineStyleListener;
import org.eclipse.swt.custom.StyleRange;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.widgets.Control;
import org.eclipse.wb.swt.SWTResourceManager;
// Adapted from http://www.java2s.com/Code/Java/SWT-JFace-Eclipse/JavaSourcecodeViewer.htm
public class RelLineStyler implements LineStyleListener {
private RelScanner scanner;
private Color[] tokenColors;
private Vector<int[]> blockComments = new Vector<int[]>();
private String[] keywords;
public static final int EOF = -1;
public static final int EOL = 10;
public static final int WORD = 0;
public static final int WHITESPACE = 1;
public static final int KEYWORD = 2;
public static final int COMMENT = 3;
public static final int STRING = 5;
public static final int OTHER = 6;
public static final int NUMBER = 7;
public static final int MAXIMUM_TOKEN = 8;
public RelLineStyler(String[] keywords) {
this.keywords = keywords;
scanner = new RelScanner();
initializeColors();
scanner = new RelScanner();
}
Color getColor(int type) {
if (type < 0 || type >= tokenColors.length) {
return null;
}
return tokenColors[type];
}
boolean inBlockComment(int start, int end) {
for (int i = 0; i < blockComments.size(); i++) {
int[] offsets = (int[]) blockComments.elementAt(i);
// start of comment in the line
if ((offsets[0] >= start) && (offsets[0] <= end))
return true;
// end of comment in the line
if ((offsets[1] >= start) && (offsets[1] <= end))
return true;
if ((offsets[0] <= start) && (offsets[1] >= end))
return true;
}
return false;
}
void initializeColors() {
tokenColors = new Color[MAXIMUM_TOKEN];
tokenColors[WORD] = SWTResourceManager.getColor(SWT.COLOR_BLACK);
tokenColors[WHITESPACE] = SWTResourceManager.getColor(SWT.COLOR_BLACK);
tokenColors[KEYWORD] = SWTResourceManager.getColor(SWT.COLOR_DARK_RED);
tokenColors[COMMENT] = SWTResourceManager.getColor(SWT.COLOR_DARK_GREEN);
tokenColors[STRING] = SWTResourceManager.getColor(SWT.COLOR_DARK_BLUE);
tokenColors[OTHER] = SWTResourceManager.getColor(SWT.COLOR_BLACK);
tokenColors[NUMBER] = SWTResourceManager.getColor(SWT.COLOR_BLACK);
}
/**
* Event.detail line start offset (input) Event.text line text (input)
* LineStyleEvent.styles Enumeration of StyleRanges, need to be in order.
* (output) LineStyleEvent.background line background color (output)
*/
public void lineGetStyle(LineStyleEvent event) {
Vector<StyleRange> styles = new Vector<StyleRange>();
int token;
StyleRange lastStyle;
// If the line is part of a block comment, create one style for the entire line.
if (inBlockComment(event.lineOffset, event.lineOffset + event.lineText.length())) {
styles.addElement(new StyleRange(event.lineOffset, event.lineText.length(), getColor(COMMENT), null));
event.styles = new StyleRange[styles.size()];
styles.copyInto(event.styles);
return;
}
Color defaultFgColor = ((Control) event.widget).getForeground();
scanner.setRange(event.lineText);
token = scanner.nextToken();
while (token != EOF) {
if (token == OTHER) {
// do nothing for non-colored tokens
} else if (token != WHITESPACE) {
Color color = getColor(token);
// Only create a style if the token color is different than the
// widget's default foreground color and the token's style is
// not
// bold. Keywords are bolded.
if ((!color.equals(defaultFgColor)) || (token == KEYWORD)) {
StyleRange style = new StyleRange(scanner.getStartOffset() + event.lineOffset, scanner.getLength(),
color, null);
/*
if (token == KEYWORD) {
style.fontStyle = SWT.BOLD;
}
*/
if (styles.isEmpty()) {
styles.addElement(style);
} else {
// Merge similar styles. Doing so will improve performance.
lastStyle = (StyleRange) styles.lastElement();
if (lastStyle.similarTo(style) && (lastStyle.start + lastStyle.length == style.start)) {
lastStyle.length += style.length;
} else {
styles.addElement(style);
}
}
}
} else if ((!styles.isEmpty()) && ((lastStyle = (StyleRange) styles.lastElement()).fontStyle == SWT.BOLD)) {
int start = scanner.getStartOffset() + event.lineOffset;
lastStyle = (StyleRange) styles.lastElement();
// A font style of SWT.BOLD implies that the last style
// represents a java keyword.
if (lastStyle.start + lastStyle.length == start) {
// Have the white space take on the style before it to
// minimize the number of style ranges created and the
// number of font style changes during rendering.
lastStyle.length += scanner.getLength();
}
}
token = scanner.nextToken();
}
event.styles = new StyleRange[styles.size()];
styles.copyInto(event.styles);
}
public void parseBlockComments(String text) {
blockComments = new Vector<int[]>();
StringReader buffer = new StringReader(text);
int ch;
boolean blkComment = false;
int cnt = 0;
int[] offsets = new int[2];
boolean done = false;
try {
while (!done) {
switch (ch = buffer.read()) {
case -1: {
if (blkComment) {
offsets[1] = cnt;
blockComments.addElement(offsets);
}
done = true;
break;
}
case '/': {
ch = buffer.read();
if ((ch == '*') && (!blkComment)) {
offsets = new int[2];
offsets[0] = cnt;
blkComment = true;
cnt++;
} else {
cnt++;
}
cnt++;
break;
}
case '*': {
if (blkComment) {
ch = buffer.read();
cnt++;
if (ch == '/') {
blkComment = false;
offsets[1] = cnt;
blockComments.addElement(offsets);
}
}
cnt++;
break;
}
default: {
cnt++;
break;
}
}
}
} catch (IOException e) {
// ignore errors
}
}
/**
* A simple fuzzy scanner for Rel
*/
private class RelScanner {
protected Hashtable<String, Integer> fgKeys = null;
protected StringBuffer fBuffer = new StringBuffer();
protected String fDoc;
protected int fPos;
protected int fEnd;
protected int fStartToken;
// protected boolean fEofSeen = false;
public RelScanner() {
initialize();
}
/**
* Returns the ending location of the current token in the document.
*/
public final int getLength() {
return fPos - fStartToken;
}
/**
* Initialize the lookup table.
*/
void initialize() {
fgKeys = new Hashtable<String, Integer>();
Integer k = new Integer(KEYWORD);
for (int i = 0; i < keywords.length; i++)
fgKeys.put(keywords[i], k);
}
/**
* Returns the starting location of the current token in the document.
*/
public final int getStartOffset() {
return fStartToken;
}
/**
* Returns the next lexical token in the document.
*/
public int nextToken() {
int c;
fStartToken = fPos;
while (true) {
switch (c = read()) {
case EOF:
return EOF;
case '/': // comment
c = read();
if (c == '/') {
while (true) {
c = read();
if ((c == EOF) || (c == EOL)) {
unread(c);
return COMMENT;
}
}
} else {
unread(c);
}
return OTHER;
case '\'': // char const
for (;;) {
c = read();
switch (c) {
case '\'':
return STRING;
case EOF:
unread(c);
return STRING;
case '\\':
c = read();
break;
}
}
case '"': // string
for (;;) {
c = read();
switch (c) {
case '"':
return STRING;
case EOF:
unread(c);
return STRING;
case '\\':
c = read();
break;
}
}
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
do {
c = read();
} while (Character.isDigit((char) c));
unread(c);
return NUMBER;
default:
if (Character.isWhitespace((char) c)) {
do {
c = read();
} while (Character.isWhitespace((char) c));
unread(c);
return WHITESPACE;
}
if (Character.isJavaIdentifierStart((char) c)) {
fBuffer.setLength(0);
do {
fBuffer.append((char) c);
c = read();
} while (Character.isJavaIdentifierPart((char) c));
unread(c);
Integer i = (Integer) fgKeys.get(fBuffer.toString().toUpperCase());
if (i != null)
return i.intValue();
return WORD;
}
return OTHER;
}
}
}
/**
* Returns next character.
*/
protected int read() {
if (fPos <= fEnd) {
return fDoc.charAt(fPos++);
}
return EOF;
}
public void setRange(String text) {
fDoc = text;
fPos = 0;
fEnd = fDoc.length() - 1;
}
protected void unread(int c) {
if (c != EOF)
fPos--;
}
}
}