javacharformatter.java

SRI international 发布的OAA框架软件

package antlr_oaa;

/* ANTLR Translator Generator
 * Project led by Terence Parr at http://www.jGuru.com
 * Software rights: http://www.antlr.org/RIGHTS.html
 *
 * $Id: JavaCharFormatter.java,v 1.1 2002/11/08 17:37:58 agno Exp $
 */

class JavaCharFormatter implements CharFormatter {


    /** Given a character value, return a string representing the character
     * that can be embedded inside a string literal or character literal
     * This works for Java/C/C++ code-generation and languages with compatible
     * special-character-escapment.
     * Code-generators for languages should override this method.
     * @param c   The character of interest.
     * @param forCharLiteral  true to escape for char literal, false for string literal
     */
    public String escapeChar(int c, boolean forCharLiteral) {
	switch (c) {
	    //		case GrammarAnalyzer.EPSILON_TYPE : return "<end-of-token>";
	case '\n' : return "\\n";
	case '\t' : return "\\t";
	case '\r' : return "\\r";
	case '\\' : return "\\\\";
	case '\'' : return forCharLiteral ? "\\'" : "'";
	case '"' :  return forCharLiteral ? "\"" : "\\\"";
	default :
	    if ( c<' '||c>126 ) {
                if ( ( 0x0000 <= c ) && ( c <= 0x000F ) ) {
                    return "\\u000" + Integer.toString(c,16);
                } else if ( ( 0x0010 <= c ) && ( c <= 0x00FF ) ) {
                    return "\\u00" + Integer.toString(c,16);
                } else if ( ( 0x0100 <= c ) && ( c <= 0x0FFF )) {
                    return "\\u0" + Integer.toString(c,16);
                } else {
                    return "\\u" + Integer.toString(c,16);
                }
	    }
	    else {
		return String.valueOf((char)c);
	    }
	}
    }
    /** Converts a String into a representation that can be use as a literal
	 * when surrounded by double-quotes.
	 * @param s The String to be changed into a literal
	 */
    public String escapeString(String s)
    {
	String retval = new String();
	for (int i = 0; i < s.length(); i++)
	    {
		retval += escapeChar(s.charAt(i), false);
	    }
	return retval;
    }
    /** Given a character value, return a string representing the character
	 * literal that can be recognized by the target language compiler.
	 * This works for languages that use single-quotes for character literals.
	 * Code-generators for languages should override this method.
	 * @param c   The character of interest.
	 */
    public String literalChar(int c) {
	return "'"  + escapeChar(c, true) + "'";
    }
    /** Converts a String into a string literal
	 * This works for languages that use double-quotes for string literals.
	 * Code-generators for languages should override this method.
	 * @param s The String to be changed into a literal
	 */
    public String literalString(String s)
    {
	return "\"" + escapeString(s) + "\"";
    }
}