package org.drools.lang;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Stack;
import java.util.Map.Entry;
import org.antlr.runtime.EarlyExitException;
import org.antlr.runtime.FailedPredicateException;
import org.antlr.runtime.MismatchedNotSetException;
import org.antlr.runtime.MismatchedSetException;
import org.antlr.runtime.MismatchedTokenException;
import org.antlr.runtime.MismatchedTreeNodeException;
import org.antlr.runtime.NoViableAltException;
import org.antlr.runtime.RecognitionException;
import org.antlr.runtime.Token;
import org.drools.compiler.DroolsParserException;
/**
* Helper class that generates DroolsParserException with user friendly error
* messages.
*
* @author porcelli
* @see DroolsParserException
*/
public class DroolsParserExceptionFactory {
public final static String MISMATCHED_TOKEN_MESSAGE_COMPLETE = "Line %1$d:%2$d mismatched input '%3$s' expecting '%4$s'%5$s";
public final static String MISMATCHED_TOKEN_MESSAGE_PART = "Line %1$d:%2$d mismatched input '%3$s'%4$s";
public final static String MISMATCHED_TREE_NODE_MESSAGE_COMPLETE = "Line %1$d:%2$d mismatched tree node '%3$s' expecting '%4$s'%5$s";
public final static String MISMATCHED_TREE_NODE_MESSAGE_PART = "Line %1$d:%2$d mismatched tree node '%3$s'%4$s";
public final static String NO_VIABLE_ALT_MESSAGE = "Line %1$d:%2$d no viable alternative at input '%3$s'%4$s";
public final static String EARLY_EXIT_MESSAGE = "Line %1$d:%2$d required (...)+ loop did not match anything at input '%3$s'%4$s";
public final static String MISMATCHED_SET_MESSAGE = "Line %1$d:%2$d mismatched input '%3$' expecting set '%4$s'%5$s.";
public final static String MISMATCHED_NOT_SET_MESSAGE = "Line %1$d:%2$d mismatched input '%3$' expecting set '%4$s'%5$s";
public final static String FAILED_PREDICATE_MESSAGE = "Line %1$d:%2$d rule '%3$s' failed predicate: {%4$s}?%5$s";
public final static String TRAILING_SEMI_COLON_NOT_ALLOWED_MESSAGE = "Line %1$d:%2$d trailing semi-colon not allowed%3$s";
public final static String PARSER_LOCATION_MESSAGE_COMPLETE = " in %1$s %2$s";
public final static String PARSER_LOCATION_MESSAGE_PART = " in %1$s";
private String[] tokenNames = null;
private Stack<Map<DroolsParaphraseTypes, String>> paraphrases = null;
/**
* DroolsParserErrorMessages constructor.
*
* @param tokenNames
* tokenNames generated by ANTLR
* @param paraphrases
* paraphrases parser structure
*/
public DroolsParserExceptionFactory(String[] tokenNames,
Stack<Map<DroolsParaphraseTypes, String>> paraphrases) {
this.tokenNames = tokenNames;
this.paraphrases = paraphrases;
}
/**
* This method creates a DroolsParserException for trailing semicolon
* exception, full of information.
*
* @param line
* line number
* @param column
* column position
* @param offset
* char offset
* @return DroolsParserException filled.
*/
public DroolsParserException createTrailingSemicolonException(int line,
int column, int offset) {
String message = String
.format(
DroolsParserExceptionFactory.TRAILING_SEMI_COLON_NOT_ALLOWED_MESSAGE,
line, column, formatParserLocation());
return new DroolsParserException("ERR 108", message, line, column,
offset, null);
}
/**
* This method creates a DroolsParserException full of information.
*
* @param e
* original exception
* @return DroolsParserException filled.
*/
public DroolsParserException createDroolsException(RecognitionException e) {
List<String> codeAndMessage = createErrorMessage(e);
return new DroolsParserException(codeAndMessage.get(1), codeAndMessage
.get(0), e.line, e.charPositionInLine, e.index, e);
}
/**
* This will take a RecognitionException, and create a sensible error
* message out of it
*/
private List<String> createErrorMessage(RecognitionException e) {
List<String> codeAndMessage = new ArrayList<String>(2);
String message = "";
if (e instanceof MismatchedTokenException) {
MismatchedTokenException mte = (MismatchedTokenException) e;
if (mte.expecting >= 0 && mte.expecting < tokenNames.length) {
message = String
.format(
DroolsParserExceptionFactory.MISMATCHED_TOKEN_MESSAGE_COMPLETE,
e.line, e.charPositionInLine,
getBetterToken(e.token),
getBetterToken(mte.expecting),
formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 101");
} else {
message = String
.format(
DroolsParserExceptionFactory.MISMATCHED_TOKEN_MESSAGE_PART,
e.line, e.charPositionInLine,
getBetterToken(e.token), formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 101");
}
} else if (e instanceof MismatchedTreeNodeException) {
MismatchedTreeNodeException mtne = (MismatchedTreeNodeException) e;
if (mtne.expecting >= 0 && mtne.expecting < tokenNames.length) {
message = String
.format(
DroolsParserExceptionFactory.MISMATCHED_TREE_NODE_MESSAGE_COMPLETE,
e.line, e.charPositionInLine,
getBetterToken(e.token),
getBetterToken(mtne.expecting),
formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 102");
} else {
message = String
.format(
DroolsParserExceptionFactory.MISMATCHED_TREE_NODE_MESSAGE_PART,
e.line, e.charPositionInLine,
getBetterToken(e.token), formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 102");
}
} else if (e instanceof NoViableAltException) {
// NoViableAltException nvae = (NoViableAltException) e;
message = String.format(
DroolsParserExceptionFactory.NO_VIABLE_ALT_MESSAGE, e.line,
e.charPositionInLine, getBetterToken(e.token),
formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 103");
} else if (e instanceof EarlyExitException) {
// EarlyExitException eee = (EarlyExitException) e;
message = String.format(
DroolsParserExceptionFactory.EARLY_EXIT_MESSAGE, e.line,
e.charPositionInLine, getBetterToken(e.token),
formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 104");
} else if (e instanceof MismatchedSetException) {
MismatchedSetException mse = (MismatchedSetException) e;
message = String.format(
DroolsParserExceptionFactory.MISMATCHED_SET_MESSAGE,
e.line, e.charPositionInLine, getBetterToken(e.token),
mse.expecting, formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 105");
} else if (e instanceof MismatchedNotSetException) {
MismatchedNotSetException mse = (MismatchedNotSetException) e;
message = String.format(
DroolsParserExceptionFactory.MISMATCHED_NOT_SET_MESSAGE,
e.line, e.charPositionInLine, getBetterToken(e.token),
mse.expecting, formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 106");
} else if (e instanceof FailedPredicateException) {
FailedPredicateException fpe = (FailedPredicateException) e;
message = String.format(
DroolsParserExceptionFactory.FAILED_PREDICATE_MESSAGE,
e.line, e.charPositionInLine, fpe.ruleName,
fpe.predicateText, formatParserLocation());
codeAndMessage.add(message);
codeAndMessage.add("ERR 107");
}
if (codeAndMessage.get(0).length() == 0) {
codeAndMessage.add("?????");
}
return codeAndMessage;
}
/**
* This will take Paraphrases stack, and create a sensible location
*/
private String formatParserLocation() {
StringBuilder sb = new StringBuilder();
for (Map<DroolsParaphraseTypes, String> map : paraphrases) {
for (Entry<DroolsParaphraseTypes, String> activeEntry : map
.entrySet()) {
if (activeEntry.getValue().length() == 0) {
sb.append(String.format(PARSER_LOCATION_MESSAGE_PART,
getLocationName(activeEntry.getKey())));
} else {
sb.append(String.format(PARSER_LOCATION_MESSAGE_COMPLETE,
getLocationName(activeEntry.getKey()), activeEntry
.getValue()));
}
}
}
return sb.toString();
}
/**
* Returns a string based on Paraphrase Type
*
* @param type
* Paraphrase Type
* @return a string representing the
*/
private String getLocationName(DroolsParaphraseTypes type) {
switch (type) {
case PACKAGE:
return "package";
case IMPORT:
return "import";
case FUNCTION_IMPORT:
return "function import";
case GLOBAL:
return "global";
case FUNCTION:
return "function";
case QUERY:
return "query";
case TEMPLATE:
return "template";
case RULE:
return "rule";
case RULE_ATTRIBUTE:
return "rule attribute";
case PATTERN:
return "pattern";
default:
return "";
}
}
/**
* Helper method that creates a user friendly token definition
*
* @param token
* token
* @return user friendly token definition
*/
private String getBetterToken(Token token) {
return getBetterToken(token.getType(), token.getText());
}
/**
* Helper method that creates a user friendly token definition
*
* @param tokenType
* token type
* @return user friendly token definition
*/
private String getBetterToken(int tokenType) {
return getBetterToken(tokenType, null);
}
/**
* Helper method that creates a user friendly token definition
*
* @param tokenType
* token type
* @param defaultValue
* default value for identifier token, may be null
* @return user friendly token definition
*/
private String getBetterToken(int tokenType, String defaultValue) {
switch (tokenType) {
case DRLLexer.INT:
return defaultValue == null ? "int" : defaultValue;
case DRLLexer.FLOAT:
return defaultValue == null ? "float" : defaultValue;
case DRLLexer.STRING:
return defaultValue == null ? "string" : defaultValue;
case DRLLexer.BOOL:
return defaultValue == null ? "boolean" : defaultValue;
case DRLLexer.NULL:
return "null";
case DRLLexer.THEN:
return "then";
case DRLLexer.END:
return "end";
case DRLLexer.GRAVE_ACCENT:
return "`";
case DRLLexer.SEMICOLON:
return ";";
case DRLLexer.DOT_STAR:
return ".*";
case DRLLexer.COLON:
return ":";
case DRLLexer.EQUAL:
return "==";
case DRLLexer.NOT_EQUAL:
return "!=";
case DRLLexer.GREATER:
return ">";
case DRLLexer.GREATER_EQUAL:
return ">=";
case DRLLexer.LESS:
return "<";
case DRLLexer.LESS_EQUAL:
return "<=";
case DRLLexer.ARROW:
return "->";
case DRLLexer.ID:
return defaultValue == null ? "identifier" : defaultValue;
case DRLLexer.LEFT_PAREN:
return "(";
case DRLLexer.RIGHT_PAREN:
return ")";
case DRLLexer.LEFT_SQUARE:
return "[";
case DRLLexer.RIGHT_SQUARE:
return "]";
case DRLLexer.LEFT_CURLY:
return "{";
case DRLLexer.RIGHT_CURLY:
return "}";
case DRLLexer.COMMA:
return ",";
case DRLLexer.DOT:
return ".";
case DRLLexer.DOUBLE_AMPER:
return "&&";
case DRLLexer.DOUBLE_PIPE:
return "||";
case DRLLexer.MISC:
return defaultValue == null ? "misc" : defaultValue;
case DRLLexer.EOF:
return "<eof>";
default:
return tokenType > tokenNames.length ? "unknown"
: tokenNames[tokenType];
}
}
}