sql 解析器

druid sqlparser

JsqlParser

fdb JsqlParser

package com.alibaba.druid;

import java.util.List;

import com.alibaba.druid.sql.SQLUtils;
import com.alibaba.druid.sql.ast.SQLStatement;
import com.alibaba.druid.sql.ast.statement.SQLSelect;
import com.alibaba.druid.sql.ast.statement.SQLSelectItem;
import com.alibaba.druid.sql.ast.statement.SQLSelectQueryBlock;
import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
import com.alibaba.druid.sql.parser.SQLParserUtils;
import com.alibaba.druid.sql.parser.SQLStatementParser;
import com.alibaba.druid.sql.visitor.SQLASTOutputVisitor;
import com.alibaba.druid.util.JdbcUtils;

public class ParseTest {

	public ParseTest() {
		// TODO Auto-generated constructor stub
	}

	public static void main(String[] args) {

		String sql = "select p, s.count as views, (select count(*) from Comments rc where rc.linkedId=p.id and rc.classcode='InfoPublishs') as commentNumber, (select count(*) from CollectIndexs rci where rci.toId=p.id and rci.classcode='InfoPublishs' and rci.type='favorite') as favorite FROM InfoPublishs p,UserScores s where p.id=s.linkedId and p.userInfo.id=s.userInfo.id and s.classCode='InfoPublishs' AND p.status=? ORDER BY p.createtime DESC";

		StringBuffer select = new StringBuffer();
		StringBuffer from = new StringBuffer();
		StringBuffer where = new StringBuffer();

		// parser得到AST
		SQLStatementParser parser = SQLParserUtils.createSQLStatementParser(
				sql, JdbcUtils.MYSQL);
		List<SQLStatement> stmtList = parser.parseStatementList(); //

		// 将AST通过visitor输出
		SQLASTOutputVisitor visitor = SQLUtils.createFormatOutputVisitor(from,
				stmtList, JdbcUtils.MYSQL);
		SQLASTOutputVisitor whereVisitor = SQLUtils.createFormatOutputVisitor(
				where, stmtList, JdbcUtils.MYSQL);
		
		List<SQLSelectItem> items = null;

		for (SQLStatement stmt : stmtList) {
			// stmt.accept(visitor);
			if (stmt instanceof SQLSelectStatement) {
				SQLSelectStatement sstmt = (SQLSelectStatement) stmt;
				SQLSelect sqlselect = sstmt.getSelect();
				SQLSelectQueryBlock query = (SQLSelectQueryBlock) sqlselect
						.getQuery();

				query.getFrom().accept(visitor);
				query.getWhere().accept(whereVisitor);
				items = query.getSelectList();
			}
		}
		for(SQLSelectItem s:items){
			System.out.println(s.getAlias());
		}
		
		System.out.println("--------------------------------");

		System.out.println("from=="+from.toString());
		System.out.println("select=="+select);
		System.out.println("where=="+where);
	}
}

  参考

 http://lxy19791111.iteye.com/blog/1543223

 http://my.oschina.net/taaaa/blog/74657

http://blog.csdn.net/isea533/article/details/38361911