private ExprContext expr()

in hertzbeat-alerter/src/main/java/org/apache/hertzbeat/alert/expr/AlertExpressionParser.java [299:440]
141 lines of code
20 McCabe index (conditional complexity)

	private ExprContext expr(int _p) throws RecognitionException {
		ParserRuleContext _parentctx = _ctx;
		int _parentState = getState();
		ExprContext _localctx = new ExprContext(_ctx, _parentState);
		ExprContext _prevctx = _localctx;
		int _startState = 2;
		enterRecursionRule(_localctx, 2, RULE_expr, _p);
		int _la;
		try {
			int _alt;
			enterOuterAlt(_localctx, 1);
			{
			setState(18);
			_errHandler.sync(this);
			switch (_input.LA(1)) {
			case LPAREN:
				{
				_localctx = new ParenExprContext(_localctx);
				_ctx = _localctx;
				_prevctx = _localctx;

				setState(12);
				match(LPAREN);
				setState(13);
				expr(0);
				setState(14);
				match(RPAREN);
				}
				break;
			case IDENTIFIER:
				{
				_localctx = new QueryExprContext(_localctx);
				_ctx = _localctx;
				_prevctx = _localctx;
				setState(16);
				identifier();
				}
				break;
			case NUMBER:
				{
				_localctx = new LiteralExprContext(_localctx);
				_ctx = _localctx;
				_prevctx = _localctx;
				setState(17);
				number();
				}
				break;
			default:
				throw new NoViableAltException(this);
			}
			_ctx.stop = _input.LT(-1);
			setState(34);
			_errHandler.sync(this);
			_alt = getInterpreter().adaptivePredict(_input,2,_ctx);
			while ( _alt!=2 && _alt!=org.antlr.v4.runtime.atn.ATN.INVALID_ALT_NUMBER ) {
				if ( _alt==1 ) {
					if ( _parseListeners!=null ) triggerExitRuleEvent();
					_prevctx = _localctx;
					{
					setState(32);
					_errHandler.sync(this);
					switch ( getInterpreter().adaptivePredict(_input,1,_ctx) ) {
					case 1:
						{
						_localctx = new ComparisonExprContext(new ExprContext(_parentctx, _parentState));
						((ComparisonExprContext)_localctx).left = _prevctx;
						pushNewRecursionContext(_localctx, _startState, RULE_expr);
						setState(20);
						if (!(precpred(_ctx, 6))) throw new FailedPredicateException(this, "precpred(_ctx, 6)");
						setState(21);
						((ComparisonExprContext)_localctx).op = _input.LT(1);
						_la = _input.LA(1);
						if ( !((((_la) & ~0x3f) == 0 && ((1L << _la) & 1008L) != 0)) ) {
							((ComparisonExprContext)_localctx).op = (Token)_errHandler.recoverInline(this);
						}
						else {
							if ( _input.LA(1)==Token.EOF ) matchedEOF = true;
							_errHandler.reportMatch(this);
							consume();
						}
						setState(22);
						((ComparisonExprContext)_localctx).right = expr(7);
						}
						break;
					case 2:
						{
						_localctx = new AndExprContext(new ExprContext(_parentctx, _parentState));
						((AndExprContext)_localctx).left = _prevctx;
						pushNewRecursionContext(_localctx, _startState, RULE_expr);
						setState(23);
						if (!(precpred(_ctx, 5))) throw new FailedPredicateException(this, "precpred(_ctx, 5)");
						setState(24);
						match(AND);
						setState(25);
						((AndExprContext)_localctx).right = expr(6);
						}
						break;
					case 3:
						{
						_localctx = new UnlessExprContext(new ExprContext(_parentctx, _parentState));
						((UnlessExprContext)_localctx).left = _prevctx;
						pushNewRecursionContext(_localctx, _startState, RULE_expr);
						setState(26);
						if (!(precpred(_ctx, 4))) throw new FailedPredicateException(this, "precpred(_ctx, 4)");
						setState(27);
						match(UNLESS);
						setState(28);
						((UnlessExprContext)_localctx).right = expr(5);
						}
						break;
					case 4:
						{
						_localctx = new OrExprContext(new ExprContext(_parentctx, _parentState));
						((OrExprContext)_localctx).left = _prevctx;
						pushNewRecursionContext(_localctx, _startState, RULE_expr);
						setState(29);
						if (!(precpred(_ctx, 3))) throw new FailedPredicateException(this, "precpred(_ctx, 3)");
						setState(30);
						match(OR);
						setState(31);
						((OrExprContext)_localctx).right = expr(4);
						}
						break;
					}
					} 
				}
				setState(36);
				_errHandler.sync(this);
				_alt = getInterpreter().adaptivePredict(_input,2,_ctx);
			}
			}
		}
		catch (RecognitionException re) {
			_localctx.exception = re;
			_errHandler.reportError(this, re);
			_errHandler.recover(this, re);
		}
		finally {
			unrollRecursionContexts(_parentctx);
		}
		return _localctx;
	}