/**
* Main function. Takes OQL query string as command line parameter and prints token stream version
* of that query to stdout.
*
* @param args Pass an OQL query string on the command line.
*/
public static void main(String args[]) {
Hashtable tokenTypes = new Hashtable();
tokenTypes.put(new Integer(END_OF_QUERY), "END_OF_QUERY");
tokenTypes.put(new Integer(KEYWORD_SELECT), "KEYWORD_SELECT");
tokenTypes.put(new Integer(IDENTIFIER), "IDENTIFIER");
tokenTypes.put(new Integer(KEYWORD_AS), "KEYWORD_AS");
tokenTypes.put(new Integer(COLON), "COLON");
tokenTypes.put(new Integer(KEYWORD_FROM), "KEYWORD_FROM");
tokenTypes.put(new Integer(KEYWORD_IN), "KEYWORD_IN");
tokenTypes.put(new Integer(KEYWORD_WHERE), "KEYWORD_WHERE");
tokenTypes.put(new Integer(KEYWORD_OR), "KEYWORD_OR");
tokenTypes.put(new Integer(KEYWORD_AND), "KEYWORD_AND");
tokenTypes.put(new Integer(EQUAL), "EQUAL");
tokenTypes.put(new Integer(NOT_EQUAL), "NOT_EQUAL");
tokenTypes.put(new Integer(KEYWORD_LIKE), "KEYWORD_LIKE");
tokenTypes.put(new Integer(LT), "LT");
tokenTypes.put(new Integer(LTE), "LTE");
tokenTypes.put(new Integer(GT), "GT");
tokenTypes.put(new Integer(GTE), "GTE");
tokenTypes.put(new Integer(PLUS), "PLUS");
tokenTypes.put(new Integer(MINUS), "MINUS");
tokenTypes.put(new Integer(CONCAT), "CONCAT");
tokenTypes.put(new Integer(TIMES), "TIMES");
tokenTypes.put(new Integer(DIVIDE), "DIVIDE");
tokenTypes.put(new Integer(KEYWORD_MOD), "KEYWORD_MOD");
tokenTypes.put(new Integer(KEYWORD_ABS), "KEYWORD_ABS");
tokenTypes.put(new Integer(KEYWORD_NOT), "KEYWORD_NOT");
tokenTypes.put(new Integer(LPAREN), "LPAREN");
tokenTypes.put(new Integer(RPAREN), "RPAREN");
tokenTypes.put(new Integer(DOLLAR), "DOLLAR");
tokenTypes.put(new Integer(KEYWORD_NIL), "KEYWORD_NIL");
tokenTypes.put(new Integer(KEYWORD_UNDEFINED), "KEYWORD_UNDEFINED");
tokenTypes.put(new Integer(BOOLEAN_LITERAL), "BOOLEAN_LITERAL");
tokenTypes.put(new Integer(LONG_LITERAL), "LONG_LITERAL");
tokenTypes.put(new Integer(DOUBLE_LITERAL), "DOUBLE_LITERAL");
tokenTypes.put(new Integer(CHAR_LITERAL), "CHAR_LITERAL");
tokenTypes.put(new Integer(STRING_LITERAL), "STRING_LITERAL");
tokenTypes.put(new Integer(DATE_LITERAL), "DATE_LITERAL");
tokenTypes.put(new Integer(TIME_LITERAL), "TIME_LITERAL");
tokenTypes.put(new Integer(TIMESTAMP_LITERAL), "TIMESTAMP_LITERAL");
tokenTypes.put(new Integer(KEYWORD_BETWEEN), "KEYWORD_BETWEEN");
Lexer lexer = new Lexer(args[0]);
while (lexer.hasMoreTokens()) {
try {
Token theToken = lexer.nextToken();
String tokenType = (String) tokenTypes.get(new Integer(theToken.getTokenType()));
System.out.println(tokenType + " : " + theToken.getTokenValue());
} catch (Exception e) {
System.out.println(e.toString());
e.printStackTrace(System.out);
break;
}
}
}
public Object getNext() {
// getNext() gets the next item on stack, pointed to by the stackPointer:
// - if stack is empty, it gets a token from Lexer and returns it, setting SP = 1
// **(in this case, the newly returned element is put on stack)
// - if SP is pointing to an existing element of stack, that element is returned, setting
// SP=SP+1
//
// - if SP is pointing right above stack, a new token from Lexer is returned, setting SP=SP+1
// **(in this case, the newly returned element is put on stack)
//
// if SP points to something that is way above stack, it returns an EOFToken().
if (stack.size() == 0) {
// System.out.println("I read " + lexer.peekNextToken());
if (lexer.hasMoreTokens()) {
stack.add(lexer.getNextToken());
stackPointer++;
return stack.get(stackPointer - 1);
} else return new EOFToken();
} else if (stackPointer < stack.size()) {
return stack.get(stackPointer++);
} else if (stackPointer == stack.size()) // execute this case only if
// stackpointer points to element right on top of stack, i.e. asks for a new element
{
if (lexer.hasMoreTokens()) {
stack.add(lexer.getNextToken());
return stack.get(stackPointer++);
} else return new EOFToken();
} else { // execute this case if stackpointer is point somewhere absurdly above the top of stack
if (diag2)
System.out.println(
"**Diag warning: invalid stack ref: getNext(), SP="
+ stackPointer
+ " for a stack of size "
+ stack.size());
return new EOFToken();
}
}
