Commit eb8aba96 authored by codefairy08's avatar codefairy08
Browse files

add method findFirstChildNodeBreadthFirst

parent 4819c03e

sharding-core/sharding-core-parse/sharding-core-parse-common/src/main/java/org/apache/shardingsphere/core/parse/antlr/extractor/util/ExtractorUtils.java

+27 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ import org.antlr.v4.runtime.tree.ParseTree; 


import java.util.Collection;

import java.util.LinkedList;

import java.util.Queue;



/**

 * Extractor utility.
@@ -71,6 +72,32 @@ public final class ExtractorUtils { 
        return Optional.absent();

    }

    

    /**

     * Find first child node breadth first.

     *

     * @param node start node

     * @param ruleName rule name

     * @return matched node

     */

    public static Optional<ParserRuleContext> findFirstChildNodeBreadthFirst(final ParserRuleContext node, final RuleName ruleName) {

        Queue<ParserRuleContext> parserRuleContexts = new LinkedList<>();

        parserRuleContexts.add(node);

        ParserRuleContext parserRuleContext;

        while (null != (parserRuleContext = parserRuleContexts.poll())) {

            if (parserRuleContext instanceof ParserRuleContext) {

                if (isMatchedNode((ParserRuleContext) parserRuleContext, ruleName)) {

                    return Optional.of((ParserRuleContext) parserRuleContext);

                }

                for (int i = 0; i < parserRuleContext.getChildCount(); i++) {

                    if (parserRuleContext.getChild(i) instanceof ParserRuleContext) {

                        parserRuleContexts.add((ParserRuleContext) parserRuleContext.getChild(i));

                    }

                }

            }

        }

        return Optional.absent();

    }

    

    /**

     * Find first child node none recursive.

     *