java连接oracle之查询

class QueryByTerms
{
int index = 1;//参数的位置
public ResultSet toChoose(Connection con, int chose, String var)
{
String sql = null;
switch(chose)
{
case 1:
sql = "select * from worker_main where worker_id = ?";
break;
case 2:
sql = "select * from worker_main where name = ?";
break;
}
return queryByTerms(con, sql, index, var);
}

private static ResultSet queryByTerms(Connection con, String sql, int index, String var)//调用时候进行参数的合理化判断
{
PreparedStatement pre = null;
ResultSet result = null;
try
{
pre = con.prepareStatement(sql);
pre.setString(index, var);
result = pre.executeQuery();
}
catch (SQLException e)
{
e.printStackTrace();
}
System.out.println(sql);
System.out.println(var);
return result;//返回结果进行选择输出
}
};