com.alibaba.druid.sql.ast.statement.SQLSelect Java Examples

private static String[] getColumns(String sql) {
    String[] columnNames;
    try {
        SQLStatementParser sqlStatementParser = SQLParserUtils.createSQLStatementParser(sql, JdbcUtils.MYSQL);
        SQLStatement statement = sqlStatementParser.parseStatement();
        if (statement instanceof SQLSelectStatement) {
            SQLSelect select = ((SQLSelectStatement) statement).getSelect();
            com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlSelectQueryBlock query = (com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlSelectQueryBlock) select.getQuery();
            int size = query.getSelectList().size();
            if (size == 1){
                if("*".equalsIgnoreCase(   query.getSelectList().get(0).toString())){
                    throw new Exception("unsupport * in select items:"+sql);
                }
            } {
                columnNames = new String[size];
                for (int i = 0; i < size; i++) {
                    columnNames[i] = query.getSelectList().get(i).toString();
                }
                return columnNames;
            }

        }
    }catch (Exception e){
        LOGGER.error("can not get column count",e);
    }
    return new String[]{};
}
 

private void addSubQuerys(SQLSelect sqlselect){
		/* 多个 sqlselect 之间  , equals 和 hashcode 是相同的.去重时 都被过滤掉了. */
		if(subQuerys.isEmpty()){
			subQuerys.add(sqlselect);
			return;
		}
        boolean exists = false;
		Iterator<SQLSelect> iter = subQuerys.iterator();
		while(iter.hasNext()){
			SQLSelect ss = iter.next();
			if(ss.getQuery() instanceof SQLSelectQueryBlock
					&&sqlselect.getQuery() instanceof SQLSelectQueryBlock){
				SQLSelectQueryBlock current = (SQLSelectQueryBlock)sqlselect.getQuery();
				SQLSelectQueryBlock ssqb = (SQLSelectQueryBlock)ss.getQuery();
//                  if(!sqlSelectQueryBlockEquals(ssqb,current)){
//                    subQuerys.add(sqlselect);
//                  }
                /**
                 * 修正判定逻辑，应改为全不在subQuerys中才加入<br/>
                 * 
                 * @author SvenAugustus
                 */
                if(sqlSelectQueryBlockEquals(current,ssqb)){
                   exists = true;
                   break;
                }
				}
			}
        if(!exists) {
          subQuerys.add(sqlselect);
		}
	}
 

/**
 * 获取子查询执行结果后,改写原始sql 继续执行.
 * @param statement
 * @param sqlselect
 * @param param
 * @return
 */
private String buildSql(SQLStatement statement,SQLSelect sqlselect,List param){

	SQLObject parent = sqlselect.getParent();
	RouteMiddlerReaultHandler handler = middlerResultHandler.get(parent.getClass());
	if(handler==null){
		throw new UnsupportedOperationException(parent.getClass()+" current is not supported ");
	}
	return handler.dohandler(statement, sqlselect, parent, param);
}
 

@Override
public SQLExpr toExpression() {
    SQLExpr expr = leftOperand.toExpression();
    SQLSelect sqlSelect = new SQLSelect(query);
    SQLInSubQueryExpr inSub = new SQLInSubQueryExpr(sqlSelect);
    inSub.setExpr(expr);
    inSub.setNot(isNeg);
    return inSub;
}
 

@Override
public SQLExpr toExpression() {
    SQLSelect sqlSelect = new SQLSelect(query);
    if (isAll) {
        return new SQLAllExpr(sqlSelect);
    } else {
        return new SQLAnyExpr(sqlSelect);
    }
}
 

private void replaceLimitParams(SQLParsedResult parseResult) {
	if (parseResult != null) {
		SQLStatement sqlStatement = parseResult.getStmt();
		if (parseResult.getStmt() != null && sqlStatement instanceof SQLSelectStatement) {
			SQLSelect sqlSelect = ((SQLSelectStatement) sqlStatement).getSelect();
			if (sqlSelect != null) {
				SQLSelectQuery sqlSelectQuery = sqlSelect.getQuery();
				if (sqlSelectQuery != null && sqlSelectQuery instanceof MySqlSelectQueryBlock) {
					MySqlSelectQueryBlock sqlSelectQueryBlock = (MySqlSelectQueryBlock) sqlSelectQuery;
					MySqlSelectQueryBlock.Limit limitExpr = sqlSelectQueryBlock.getLimit();
					if (limitExpr != null) {
						int offsetRefIndex = -1;
						int countRefIndex = -1;
						if (limitExpr.getOffset() instanceof SQLVariantRefExpr
						      && limitExpr.getRowCount() instanceof SQLVariantRefExpr) {
							SQLVariantRefExpr offsetExpr = (SQLVariantRefExpr) limitExpr.getOffset();
							SQLVariantRefExpr countExpr = (SQLVariantRefExpr) limitExpr.getRowCount();

							offsetRefIndex = offsetExpr.getIndex();
							countRefIndex = countExpr.getIndex();

							if (offsetRefIndex > countRefIndex && offsetRefIndex != -1 && countRefIndex != -1) {
								offsetExpr.setIndex(countRefIndex);
								countExpr.setIndex(offsetRefIndex);
							}
						}
					}
				}
			}
		}
	}
}
 

private static SQLExpr getWhere(SQLParsedResult parseResult) {
	SQLExpr expr = null;
	SQLStatement stmt = parseResult.getStmt();

	if (parseResult.getType() == SqlType.SELECT || parseResult.getType() == SqlType.SELECT_FOR_UPDATE) {
		MySqlSelectQueryBlock query = (MySqlSelectQueryBlock) (((SQLSelectStatement) stmt).getSelect()).getQuery();
		expr = query.getWhere();
	} else if (parseResult.getType() == SqlType.UPDATE) {
		expr = ((MySqlUpdateStatement) stmt).getWhere();
	} else if (parseResult.getType() == SqlType.DELETE) {
		expr = ((MySqlDeleteStatement) stmt).getWhere();
	} else if (parseResult.getType() == SqlType.REPLACE) { // add for replace
		MySqlReplaceStatement replaceStatement = (MySqlReplaceStatement) stmt;
		SQLQueryExpr queryExpr = replaceStatement.getQuery();
		if (queryExpr != null) {
			SQLSelect sqlSelect = queryExpr.getSubQuery();
			sqlSelect.getQuery();
			if (sqlSelect != null) {
				MySqlSelectQueryBlock queryBlock = (MySqlSelectQueryBlock) sqlSelect.getQuery();
				if (queryBlock != null) {
					expr = queryBlock.getWhere();
				}
			}
		}
	}

	return expr;
}
 

public Queue<SQLSelect> getSubQuerys() {
	return subQuerys;
}
 

@Override
public SQLExpr toExpression() {
    SQLSelect sqlSelect = new SQLSelect(query);
    return new SQLQueryExpr(sqlSelect);
}
 

@Override
public SQLExpr toExpression() {
    return new SQLExistsExpr(new SQLSelect(query), isNot);
}
 

/**
 * 处理中间结果
 * @param statement
 * @param sqlselect
 * @param param
 * @return
 */
String dohandler(SQLStatement statement,SQLSelect sqlselect,SQLObject parent,List param);