Commit 3f4a4131 authored by terrymanu's avatar terrymanu
Browse files

refactor PredicateExtractor

parent 9813b34c

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/impl/PredicateExtractor.java

+30 −44
Original line number Diff line number Diff line
@@ -78,36 +78,29 @@ public final class PredicateExtractor implements OptionalSQLSegmentExtractor { 
        if (index > 0) {

            Optional<OrConditionSegment> leftOrCondition = extractCondition(questionNodeIndexMap, (ParserRuleContext) exprNode.getChild(index - 1));

            Optional<OrConditionSegment> rightOrCondition = extractCondition(questionNodeIndexMap, (ParserRuleContext) exprNode.getChild(index + 1));

            return mergeCondition(leftOrCondition, rightOrCondition, exprNode.getChild(index).getText());

        } else {

            return extractConditionForParen(questionNodeIndexMap, exprNode);

        }

    }

    

    private Optional<OrConditionSegment> mergeCondition(final Optional<OrConditionSegment> leftOrCondition, final Optional<OrConditionSegment> rightOrCondition, final String operator) {

        if (!leftOrCondition.isPresent() && !rightOrCondition.isPresent()) {

            return Optional.absent();

            if (leftOrCondition.isPresent() && rightOrCondition.isPresent()) {

                return Optional.of(mergeCondition(leftOrCondition.get(), rightOrCondition.get(), exprNode.getChild(index).getText()));

            }

        if (leftOrCondition.isPresent() && !rightOrCondition.isPresent()) {

            return leftOrCondition;

            return leftOrCondition.isPresent() ? leftOrCondition : rightOrCondition;

        }

        if (rightOrCondition.isPresent() && !leftOrCondition.isPresent()) {

            return rightOrCondition;

        return extractConditionForParen(questionNodeIndexMap, exprNode);

    }

    

    private OrConditionSegment mergeCondition(final OrConditionSegment leftOrCondition, final OrConditionSegment rightOrCondition, final String operator) {

        if (LogicalOperator.isOrOperator(operator)) {

            leftOrCondition.get().getAndConditions().addAll(rightOrCondition.get().getAndConditions());

            leftOrCondition.getAndConditions().addAll(rightOrCondition.getAndConditions());

            return leftOrCondition;

        }

        OrConditionSegment result = new OrConditionSegment();

        for (AndConditionSegment each : leftOrCondition.get().getAndConditions()) {

            for (AndConditionSegment eachRightOr : rightOrCondition.get().getAndConditions()) {

        for (AndConditionSegment each : leftOrCondition.getAndConditions()) {

            for (AndConditionSegment eachRightOr : rightOrCondition.getAndConditions()) {

                AndConditionSegment tempList = new AndConditionSegment();

                tempList.getConditions().addAll(each.getConditions());

                tempList.getConditions().addAll(eachRightOr.getConditions());

                result.getAndConditions().add(tempList);

            }

        }

        return Optional.of(result);

        return result;

    }

    

    private Optional<OrConditionSegment> extractConditionForParen(final Map<ParserRuleContext, Integer> questionNodeIndexMap, final ParserRuleContext exprNode) {
@@ -126,15 +119,15 @@ public final class PredicateExtractor implements OptionalSQLSegmentExtractor { 
            return Optional.absent();

        }

        Optional<ConditionSegment> condition = buildCondition(questionNodeIndexMap, exprNode);

        if (condition.isPresent()) {

        if (!condition.isPresent()) {

            return Optional.absent();

        }

        OrConditionSegment result = new OrConditionSegment();

        AndConditionSegment newAndCondition = new AndConditionSegment();

        newAndCondition.getConditions().add(condition.get());

        result.getAndConditions().add(newAndCondition);

        return Optional.of(result);

    }

        return Optional.absent();

    }

    

    private Optional<ConditionSegment> buildCondition(final Map<ParserRuleContext, Integer> questionNodeIndexMap, final ParserRuleContext exprNode) {

        Optional<ConditionSegment> result = buildEqualCondition(questionNodeIndexMap, exprNode);
@@ -146,13 +139,7 @@ public final class PredicateExtractor implements OptionalSQLSegmentExtractor { 
    

    private Optional<ConditionSegment> buildEqualCondition(final Map<ParserRuleContext, Integer> questionNodeIndexMap, final ParserRuleContext exprNode) {

        Optional<ParserRuleContext> comparisionNode = ExtractorUtils.findFirstChildNode(exprNode, RuleName.COMPARISON_OPERATOR);

        if (!comparisionNode.isPresent()) {

            return Optional.absent();

        }

        if (!Symbol.EQ.getLiterals().equalsIgnoreCase(comparisionNode.get().getText())) {

            return Optional.absent();

        }

        if (3 != comparisionNode.get().getParent().getChildCount()) {

        if (!comparisionNode.isPresent() || !isValidEqualCondition(comparisionNode.get())) {

            return Optional.absent();

        }

        Optional<ParserRuleContext> leftNode = ExtractorUtils.findFirstChildNode((ParserRuleContext) comparisionNode.get().parent.getChild(0), RuleName.COLUMN_NAME);
@@ -161,22 +148,21 @@ public final class PredicateExtractor implements OptionalSQLSegmentExtractor { 
            return Optional.absent();

        }

        if (leftNode.isPresent() && rightNode.isPresent()) {

            Optional<ColumnSegment> column = buildColumn(leftNode.get());

            Optional<ColumnSegment> leftColumn = buildColumn(leftNode.get());

            Optional<ColumnSegment> rightColumn = buildColumn(rightNode.get());

            return Optional.of(new ConditionSegment(column.get(), ShardingOperator.EQUAL, rightColumn.get()));

            Preconditions.checkState(leftColumn.isPresent() && rightColumn.isPresent());

            return Optional.of(new ConditionSegment(leftColumn.get(), ShardingOperator.EQUAL, rightColumn.get()));

        }

        Optional<ColumnSegment> column = buildColumn(exprNode);

        ParserRuleContext valueNode;

        if (leftNode.isPresent()) {

            valueNode = (ParserRuleContext) comparisionNode.get().parent.getChild(2);

        } else {

            valueNode = (ParserRuleContext) comparisionNode.get().parent.getChild(0);

        }

        Preconditions.checkState(column.isPresent());

        ParserRuleContext valueNode = leftNode.isPresent() ? (ParserRuleContext) comparisionNode.get().parent.getChild(2) : (ParserRuleContext) comparisionNode.get().parent.getChild(0);

        Optional<ExpressionSegment> sqlExpression = buildExpression(questionNodeIndexMap, valueNode);

        if (!sqlExpression.isPresent()) {

            return Optional.absent();

        return sqlExpression.isPresent()

                ? Optional.of(new ConditionSegment(column.get(), ShardingOperator.EQUAL, new EqualsValueExpressionSegment(sqlExpression.get()))) : Optional.<ConditionSegment>absent();

    }

        return Optional.of(new ConditionSegment(column.get(), ShardingOperator.EQUAL, new EqualsValueExpressionSegment(sqlExpression.get())));

    

    private boolean isValidEqualCondition(final ParserRuleContext comparisionNode) {

        return Symbol.EQ.getLiterals().equalsIgnoreCase(comparisionNode.getText()) && 3 == comparisionNode.getParent().getChildCount();

    }

    

    private Optional<ExpressionSegment> buildExpression(final Map<ParserRuleContext, Integer> questionNodeIndexMap, final ParserRuleContext valueNode) {