ruleparser.java

jboss规则引擎

// $ANTLR 3.0ea8 /home/michael/projects/jboss-rules-3.0.x/drools-compiler/src/main/resources/org/drools/lang/drl.g 2006-08-16 14:21:20

	package org.drools.lang;
	import java.util.List;
	import java.util.ArrayList;
	import java.util.Iterator;
	import java.util.StringTokenizer;
	import org.drools.lang.descr.*;


import org.antlr.runtime.*;
import java.util.Stack;
import java.util.List;
import java.util.ArrayList;

public class RuleParser extends Parser {
    public static final String[] tokenNames = new String[] {
        "<invalid>", "<EOR>", "<DOWN>", "<UP>", "EOL", "ID", "INT", "BOOL", "STRING", "FLOAT", "MISC", "WS", "SH_STYLE_SINGLE_LINE_COMMENT", "C_STYLE_SINGLE_LINE_COMMENT", "MULTI_LINE_COMMENT", "\';\'", "\'package\'", "\'import\'", "\'.\'", "\'.*\'", "\'expander\'", "\'global\'", "\'function\'", "\'(\'", "\',\'", "\')\'", "\'{\'", "\'}\'", "\'query\'", "\'end\'", "\'rule\'", "\'when\'", "\':\'", "\'then\'", "\'attributes\'", "\'salience\'", "\'no-loop\'", "\'auto-focus\'", "\'activation-group\'", "\'agenda-group\'", "\'duration\'", "\'or\'", "\'||\'", "\'==\'", "\'>\'", "\'>=\'", "\'<\'", "\'<=\'", "\'!=\'", "\'contains\'", "\'matches\'", "\'excludes\'", "\'null\'", "\'->\'", "\'and\'", "\'&&\'", "\'exists\'", "\'not\'", "\'eval\'", "\'[\'", "\']\'", "\'use\'"
    };
    public static final int BOOL=7;
    public static final int INT=6;
    public static final int WS=11;
    public static final int EOF=-1;
    public static final int MISC=10;
    public static final int STRING=8;
    public static final int EOL=4;
    public static final int FLOAT=9;
    public static final int SH_STYLE_SINGLE_LINE_COMMENT=12;
    public static final int MULTI_LINE_COMMENT=14;
    public static final int C_STYLE_SINGLE_LINE_COMMENT=13;
    public static final int ID=5;
        public RuleParser(TokenStream input) {
            super(input);
        }
        

    public String[] getTokenNames() { return tokenNames; }


    	private ExpanderResolver expanderResolver;
    	private Expander expander;
    	private boolean expanderDebug = false;
    	private PackageDescr packageDescr;
    	private List errors = new ArrayList();
    	private String source = "unknown";
    	private int lineOffset = 0;
    	
    	private boolean parserDebug = false;
    	
    	public void setParserDebug(boolean parserDebug) {
    		this.parserDebug = parserDebug;
    	}
    	
    	public void debug(String message) {
    		if ( parserDebug ) 
    			System.err.println( "drl parser: " + message );
    	}
    	
    	public void setSource(String source) {
    		this.source = source;
    	}

    	/**
    	 * This may be set to enable debuggin of DSLs/expanders.
    	 * If set to true, expander stuff will be sent to the Std out.
    	 */	
    	public void setExpanderDebug(boolean status) {
    		expanderDebug = status;
    	}
    	public String getSource() {
    		return this.source;
    	}
    	
    	public PackageDescr getPackageDescr() {
    		return packageDescr;
    	}
    	
    	private int offset(int line) {
    		return line + lineOffset;
    	}
    	
    	/**
    	 * This will set the offset to record when reparsing. Normally is zero of course 
    	 */
    	public void setLineOffset(int i) {
    	 	this.lineOffset = i;
    	}
    	
    	public void setExpanderResolver(ExpanderResolver expanderResolver) {
    		this.expanderResolver = expanderResolver;
    	}
    	
    	public ExpanderResolver getExpanderResolver() {
    		return expanderResolver;
    	}
    	
    	/** Expand the LHS */
    	private String runWhenExpander(String text, int line) throws RecognitionException {
    		String expanded = text.trim();
    		if (expanded.startsWith(">")) {
    			expanded = expanded.substring(1);  //escape !!
    		} else {
    			try {
    				expanded = expander.expand( "when", text );			
    			} catch (Exception e) {
    				this.errors.add(new ExpanderException("Unable to expand: " + text + ". Due to " + e.getMessage(), line));
    				return "";
    			}
    		}
    		if (expanderDebug) {
    			System.out.println("Expanding LHS: " + text + " ----> " + expanded + " --> from line: " + line);
    		}
    		return expanded;	
    		
    	}
    	
        	/** This will apply a list of constraints to an LHS block */
        	private String applyConstraints(List constraints, String block) {
        		//apply the constraints as a comma seperated list inside the previous block
        		//the block will end in something like "foo()" and the constraint patterns will be put in the ()
        		if (constraints == null) {
        			return block;
        		}
        		StringBuffer list = new StringBuffer();    		
        		for (Iterator iter = constraints.iterator(); iter.hasNext();) {
    				String con = (String) iter.next();
    				list.append("\n\t\t");
    				list.append(con);
    				if (iter.hasNext()) {
    					list.append(",");					
    				}			
    			}
        		if (block.endsWith("()")) {
        			return block.substring(0, block.length() - 2) + "(" + list.toString() + ")";
        		} else {
        			return block + "(" + list.toString() + ")";
        		}
        	}  	

            /** Reparse the results of the expansion */
        	private void reparseLhs(String text, AndDescr descrs) throws RecognitionException {
        		CharStream charStream = new ANTLRStringStream( text );
        		RuleParserLexer lexer = new RuleParserLexer( charStream );
        		TokenStream tokenStream = new CommonTokenStream( lexer );
        		RuleParser parser = new RuleParser( tokenStream );
        		parser.setLineOffset( descrs.getLine() );
        		parser.normal_lhs_block(descrs);
                
                    if (parser.hasErrors()) {
        			this.errors.addAll(parser.getErrors());
        		}
    		if (expanderDebug) {
    			System.out.println("Reparsing LHS: " + text + " --> successful:" + !parser.hasErrors());
    		}    		
        		
        	}
    	
    	/** Expand a line on the RHS */
    	private String runThenExpander(String text, int startLine) {
    		//System.err.println( "expand THEN [" + text + "]" );
    		StringTokenizer lines = new StringTokenizer( text, "\n\r" );

    		StringBuffer expanded = new StringBuffer();
    		
    		String eol = System.getProperty( "line.separator" );
    				
    		while ( lines.hasMoreTokens() ) {
    			startLine++;
    			String line = lines.nextToken();
    			line = line.trim();
    			if ( line.length() > 0 ) {
    				if ( line.startsWith( ">" ) ) {
    					expanded.append( line.substring( 1 ) );
    					expanded.append( eol );
    				} else {
    					try {
    						expanded.append( expander.expand( "then", line ) );
    						expanded.append( eol );
    					} catch (Exception e) {
    						this.errors.add(new ExpanderException("Unable to expand: " + line + ". Due to " + e.getMessage(), startLine));			
    					}
    				}
    			}
    		}
    		
    		if (expanderDebug) {
    			System.out.println("Expanding RHS: " + text + " ----> " + expanded.toString() + " --> from line starting: " + startLine);
    		}		
    		
    		return expanded.toString();
    	}
    	

    	
    	private String getString(Token token) {
    		String orig = token.getText();
    		return orig.substring( 1, orig.length() -1 );
    	}
    	
    	public void reportError(RecognitionException ex) {
    	        // if we've already reported an error and have not matched a token
                    // yet successfully, don't report any errors.
                    if ( errorRecovery ) {
                            return;
                    }
                    errorRecovery = true;

    		ex.line = offset(ex.line); //add the offset if there is one
    		errors.add( ex ); 
    	}
         	
         	/** return the raw RecognitionException errors */
         	public List getErrors() {
         		return errors;
         	}
         	
         	/** Return a list of pretty strings summarising the errors */
         	public List getErrorMessages() {
         		List messages = new ArrayList();
     		for ( Iterator errorIter = errors.iterator() ; errorIter.hasNext() ; ) {
         	     		messages.add( createErrorMessage( (RecognitionException) errorIter.next() ) );
         	     	}
         	     	return messages;
         	}
         	
         	/** return true if any parser errors were accumulated */
         	public boolean hasErrors() {
      		return ! errors.isEmpty();
         	}
         	
         	/** This will take a RecognitionException, and create a sensible error message out of it */
         	public String createErrorMessage(RecognitionException e)
            {
    		StringBuffer message = new StringBuffer();		
                    message.append( source + ":"+e.line+":"+e.charPositionInLine+" ");
                    if ( e instanceof MismatchedTokenException ) {
                            MismatchedTokenException mte = (MismatchedTokenException)e;
                            message.append("mismatched token: "+
                                                               e.token+
                                                               "; expecting type "+
                                                               tokenNames[mte.expecting]);
                    }
                    else if ( e instanceof MismatchedTreeNodeException ) {
                            MismatchedTreeNodeException mtne = (MismatchedTreeNodeException)e;
                            message.append("mismatched tree node: "+
                                                               mtne.foundNode+
                                                               "; expecting type "+
                                                               tokenNames[mtne.expecting]);
                    }
                    else if ( e instanceof NoViableAltException ) {
                            NoViableAltException nvae = (NoViableAltException)e;
    			message.append( "Unexpected token '" + e.token.getText() + "'" );
                            /*
                            message.append("decision=<<"+nvae.grammarDecisionDescription+">>"+
                                                               " state "+nvae.stateNumber+
                                                               " (decision="+nvae.decisionNumber+
                                                               ") no viable alt; token="+
                                                               e.token);
                                                               */
                    }
                    else if ( e instanceof EarlyExitException ) {
                            EarlyExitException eee = (EarlyExitException)e;
                            message.append("required (...)+ loop (decision="+
                                                               eee.decisionNumber+
                                                               ") did not match anything; token="+
                                                               e.token);
                    }
                    else if ( e instanceof MismatchedSetException ) {
                            MismatchedSetException mse = (MismatchedSetException)e;
                            message.append("mismatched token '"+
                                                               e.token+
                                                               "' expecting set "+mse.expecting);
                    }
                    else if ( e instanceof MismatchedNotSetException ) {
                            MismatchedNotSetException mse = (MismatchedNotSetException)e;
                            message.append("mismatched token '"+
                                                               e.token+
                                                               "' expecting set "+mse.expecting);
                    }
                    else if ( e instanceof FailedPredicateException ) {
                            FailedPredicateException fpe = (FailedPredicateException)e;
                            message.append("rule "+fpe.ruleName+" failed predicate: {"+
                                                               fpe.predicateText+"}?");
                    } else if (e instanceof GeneralParseException) {
    			message.append(" " + e.getMessage());
    		}
                   	return message.toString();
            }   
            
            void checkTrailingSemicolon(String text, int line) {
            	if (text.trim().endsWith( ";" ) ) {
            		this.errors.add( new GeneralParseException( "Trailing semi-colon not allowed", offset(line) ) );
            	}
            }
          



    // $ANTLR start opt_eol
    // /home/michael/projects/jboss-rules-3.0.x/drools-compiler/src/main/resources/org/drools/lang/drl.g:275:1: opt_eol : ( (';'|EOL))* ;
    public void opt_eol() throws RecognitionException {   
        try {
            // /home/michael/projects/jboss-rules-3.0.x/drools-compiler/src/main/resources/org/drools/lang/drl.g:276:17: ( ( (';'|EOL))* )
            // /home/michael/projects/jboss-rules-3.0.x/drools-compiler/src/main/resources/org/drools/lang/drl.g:276:17: ( (';'|EOL))*
            {
            // /home/michael/projects/jboss-rules-3.0.x/drools-compiler/src/main/resources/org/drools/lang/drl.g:276:17: ( (';'|EOL))*
            loop1:
            do {
                int alt1=2;
                int LA1_0 = input.LA(1);
                if ( LA1_0==EOL ) {
                    alt1=1;
                }
                else if ( LA1_0==15 ) {
                    alt1=1;
                }


                switch (alt1) {
            	case 1 :
            	    // /home/michael/projects/jboss-rules-3.0.x/drools-compiler/src/main/resources/org/drools/lang/drl.g:276:18: (';'|EOL)
            	    {
            	    if ( input.LA(1)==EOL||input.LA(1)==15 ) {
            	        input.consume();
            	        errorRecovery=false;
            	    }
            	    else {
            	        MismatchedSetException mse =
            	            new MismatchedSetException(null,input);
            	        recoverFromMismatchedSet(input,mse,FOLLOW_set_in_opt_eol41);    throw mse;
            	    }


            	    }