druid的SQLParser解析HQL语句

http://my.oschina.net/taaaa/blog/74657
让druid的SQLParser解析HQL语句,生成SELECT ......FROM.....WHERE ......的形式,闲话少说,直接上例子:

package com.alibaba.druid;

import java.util.List; 
import com.alibaba.druid.sql.SQLUtils; 
import com.alibaba.druid.sql.ast.SQLExpr; 
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.SQLSelectQuery; 
import com.alibaba.druid.sql.ast.statement.SQLSelectQueryBlock; 
import com.alibaba.druid.sql.ast.statement.SQLSelectStatement; 
import com.alibaba.druid.sql.parser.SQLExprParser; 
import com.alibaba.druid.sql.parser.SQLParserUtils; 
import com.alibaba.druid.sql.parser.SQLSelectParser; 
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=?1 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 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); 
   
 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); 
 } 
 } 
  
 System.out.println(from.toString()); 
 System.out.println(select); 
 System.out.println(where); 
 } 
}


输出结果是:

InfoPublishs p, UserScores s


p.id = s.linkedId
AND p.userInfo.id = s.userInfo.id
AND s.classCode = 'InfoPublishs'
AND p.status = ?1

大家觉得怎么样呢?觉的有用就收着吧,没用就扔了。


上面例子有些问题, 不知道是版本还是什么原因,
下面这个例子, 如果真的要实用, 还得修改
public static void sqlDecomposition(String query,boolean isPrefix) throws InterruptedException {
        //Map<String,AnalysisPool> apMap=new HashMap<String,AnalysisPool>();
        StringBuffer from=new StringBuffer();
        SQLStatementParser parser=SQLParserUtils.createSQLStatementParser(query,JdbcUtils.HIVE);
        List<SQLStatement> stmtList=parser.parseStatementList();
        SQLASTOutputVisitor visitor=SQLUtils.createFormatOutputVisitor(from,stmtList,JdbcUtils.HIVE);
        List<SQLSelectItem> sL=new ArrayList<SQLSelectItem>();
        SQLStatement stmt=stmtList.iterator().next();
        SQLSelectStatement sstmt=(SQLSelectStatement)stmt;
        SQLSelect sqlselect=sstmt.getSelect();
        SQLSelectQueryBlock sqb=(SQLSelectQueryBlock)sqlselect.getQuery();
        SQLTableSource fromx=sqb.getFrom();
        fromx.accept(visitor);
        sL=sqb.getSelectList();
        StringBuffer sb=new StringBuffer();
        for (  SQLSelectItem sqi : sL) {
            if (sqi.getExpr() instanceof SQLCaseExpr) {
                sb.append(sqi.getAlias()).append(",");
            }
            else {
                sb.append(sqi.toString()).append(",");
            }
        }
        System.out.println("* ???? : " + sb.toString().substring(0, sb.toString().length() - 1));
        //sourceAnalysis(fromx,apMap);
    }

猜你喜欢

转载自panyongzheng.iteye.com/blog/2100963