Re: How to retrieve jsonb column through JDBC - Mailing list pgsql-general

From Alban Hertroys
Subject Re: How to retrieve jsonb column through JDBC
Date
Msg-id 47F8D0CB-C635-4BDB-87DF-CC6823346A4A@gmail.com
Whole thread Raw
In response to Re: How to retrieve jsonb column through JDBC  (Alexander Farber <alexander.farber@gmail.com>)
List pgsql-general
> On 29 Aug 2016, at 20:23, Alexander Farber <alexander.farber@gmail.com> wrote:
> On Mon, Aug 29, 2016 at 7:50 PM, Merlin Moncure <mmoncure@gmail.com> wrote:
> On Sat, Aug 27, 2016 at 5:39 AM, Alexander Farber
> <alexander.farber@gmail.com> wrote:
> >
> >          List last_tiles = (List) JSON.parse(rs.getString("last_tiles"));
> >
> > has not work for me even though the string is:
> >
> >  [{"col": 7, "row": 8, "value": 1, "letter": "A"}, {"col": 7, "row": 7,
> > "value": 2, "letter": "B"}, {"col": 7, "row": 9, "value": 2, "letter": "C"}]
> >
> > but it is probably the problem of the Jetty class I am using and not of
> > JDBC...
>
> huh.  what exactly is failing? are you getting a parse exception?
>
>
http://download.eclipse.org/jetty/9.3.11.v20160721/apidocs/org/eclipse/jetty/util/ajax/JSON.html#parse-java.lang.String-
>
> fails with:
>
> java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to java.util.List

I'm not 100% sure it's the root of the ClassCastException here, but I'm pretty sure that Java will want to know what
classof items that List consists of. 
If that doesn't ring a bell for you, spend some time reading about "Java generic classes" (not to be confused with
"generalJava classes"). 

Alban Hertroys
--
If you can't see the forest for the trees,
cut the trees and you'll find there is no forest.



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