rule.java

SRI international 发布的OAA框架软件

package antlr_oaa.preprocessor;

/* ANTLR Translator Generator
 * Project led by Terence Parr at http://www.jGuru.com
 * Software rights: http://www.antlr.org/RIGHTS.html
 *
 * $Id: Rule.java,v 1.1 2002/11/08 17:36:56 agno Exp $
 */

import antlr_oaa.collections.impl.IndexedVector;
import java.util.Hashtable;
import java.util.Enumeration;

class Rule {
	protected String name;
	protected String block;
	protected String args;
	protected String returnValue;
	protected String throwsSpec;
	protected String initAction;
  	protected IndexedVector options;
	protected String visibility;
	protected Grammar enclosingGrammar;
	protected boolean bang = false;

	public Rule(String n, String b, IndexedVector options, Grammar gr) {
		name = n;
		block = b;
		this.options = options;
		setEnclosingGrammar(gr);
	}
	public String getArgs() { return args; }
	public boolean getBang() { return bang; }
	public String getName() { return name; }
	public String getReturnValue() { return returnValue; }
	public String getVisibility() { return visibility; }
	/** If 'rule' narrows the visible of 'this', return true;
	 *  For example, 'this' is public and 'rule' is private,
	 *  true is returned.  You cannot narrow the vis. of
	 *  a rule.
	 */
	public boolean narrowerVisibility(Rule rule) {
		if ( visibility.equals("public") ) {
			if ( !rule.equals("public") ) {
				return true;	// everything narrower than public
			}
			return false;
		}
		else if ( visibility.equals("protected") ) {
			if ( rule.equals("private") ) {
				return true;	// private narrower than protected
			}
			return false;
		}
		else if ( visibility.equals("private") ) {
			return false;	// nothing is narrower than private
		}
		return false;
	}
	/** Two rules have the same signature if they have:
	 *  	same name
	 *		same return value
	 *		same args
	 *	I do a simple string compare now, but later
	 *	the type could be pulled out so it is insensitive
	 *	to names of args etc...
	 */
	public boolean sameSignature(Rule rule) {
		boolean nSame=true;
		boolean aSame=true;
		boolean rSame=true;

		nSame = name.equals(rule.getName());
		if ( args!=null ) {
			aSame = args.equals(rule.getArgs());
		}
		if ( returnValue!=null ) {
			rSame = returnValue.equals(rule.getReturnValue());
		}
		return nSame && aSame && rSame;
	}
	public void setArgs(String a) { args=a; }
	public void setBang() {bang=true;}
	public void setEnclosingGrammar(Grammar g) { enclosingGrammar=g; }
	public void setInitAction(String a) {initAction = a;}
	public void setOptions(IndexedVector options) {
		this.options = options;
	}
	public void setReturnValue(String ret) { returnValue=ret; }
	public void setThrowsSpec(String t) { throwsSpec=t; }
	public void setVisibility(String v) { visibility=v; }
	public String toString() {
		String s="";
		String retString = returnValue==null ? "" : "returns "+returnValue;
		String argString = args==null ? "" : args;
		String bang = getBang() ? "!" : "";

		s += visibility==null ? "" : visibility+" ";
		s += name+bang+argString+" "+retString+throwsSpec;
		if ( options!=null ) {
			s += System.getProperty("line.separator")+
				 "options {"+
				 System.getProperty("line.separator");
			for (Enumeration e = options.elements() ; e.hasMoreElements() ;) {
				s += (Option)e.nextElement()+System.getProperty("line.separator");
			}
			s += "}"+System.getProperty("line.separator");
		}
		if ( initAction!=null ) {
			s+=initAction+System.getProperty("line.separator");
		}	
		s += block;
		return s;
	}
}