Hi Chiwan,
I followed instructions in documentation.
I have a simple base class with some properties (all public).
Then I extend that class with a new public property (tweet in my case), I
provide also getter and setter for that property.
Now when I execute:
DataSet<TwitterPOJO> ds_twitter = env.readCsvFile("file://"+path_twitter)
.pojoType(TwitterPOJO.class, "table", "time", "tweet");
I receive:
There is no field called "table" in com.Flink.POJO.TwitterPOJO
table is a field of the Base class, declared as public with also getter and
setter.
Thank you for your help.
Giacomo
On Wed, Sep 16, 2015 at 4:42 PM, Chiwan Park <chiwanp...@apache.org> wrote:
> Hi Giacomo,
>
> You should set your field as public. If you are set your field as private
> or protected, the class must provide getter and setter to be treated as
> POJO.
>
> Maybe the documentation in homepage [1] would be helpful.
>
> Regards,
> Chiwan Park
>
> [1]
> https://ci.apache.org/projects/flink/flink-docs-master/apis/programming_guide.html#pojos
>
> > On Sep 16, 2015, at 11:25 PM, Giacomo Licari <giacomo.lic...@gmail.com>
> wrote:
> >
> > I run it only implementing java.io.Serializable without disabling the
> closure cleaner.
> >
> > Another question I have is about POJO classes.
> > I would also create a base POJO class with some common proprerties, and
> then extend it in new classes. These classes are used to convert a CSV into
> a dataset of POJO objects (of derived class type).
> >
> > In the following example, I create a DataSet of TwitterPOJO, which
> extends a Base class, adding the new property "tweet".
> >
> > DataSet<TwitterPOJO> ds_twitter = env.readCsvFile("file://"+path_twitter)
> > .pojoType(TwitterPOJO.class, "table", "time",
> "tweet");
> >
> > I obtain this error:
> > [main] INFO org.apache.flink.api.java.typeutils.TypeExtractor - class
> com.Flink.POJO.TwitterPOJO is not a valid POJO type
> > Exception in thread "main" java.lang.ClassCastException:
> org.apache.flink.api.java.typeutils.GenericTypeInfo cannot be cast to
> org.apache.flink.api.java.typeutils.PojoTypeInfo
> >
> > Greetings,
> > G.L.
> >
> > On Wed, Sep 16, 2015 at 4:05 PM, Stephan Ewen <se...@apache.org> wrote:
> > Could you also try the other variant (disabeling the closure cleaner)? I
> would be curious if this behavior is expected Java Serialization behavior,
> or whether our pre-processing code is causing it.
> >
> > Greetings,
> > Stephan
> >
> >
> > On Wed, Sep 16, 2015 at 3:38 PM, Giacomo Licari <
> giacomo.lic...@gmail.com> wrote:
> > Thank you Martin and Stephan for your help.
> > I tried directly to implement java.io.Serializable in Base class and it
> worked perfectly!
> >
> > Now I can develop more flexible and maintainable code. Thank you a lot
> guys.
> >
> > Greetings,
> > Giacomo
> >
> > On Wed, Sep 16, 2015 at 1:46 PM, Stephan Ewen <se...@apache.org> wrote:
> > Hi!
> >
> > Interesting case. We use plain Java Serialization to distribute UDFs,
> and perform additional "cleaning" of scopes, which may be causing the issue.
> >
> > Can you try the following to see if any of those resolves the problem?
> >
> > 1) On the environment, disable the closure cleaner (in the execution
> config).
> >
> > 2) Let the CullTimeBase class implement java.io.Serializable.
> >
> > Please let us know how it turns out!
> >
> > Greetings,
> > Stephan
> >
> >
> > On Wed, Sep 16, 2015 at 1:29 PM, Martin Junghanns <
> m.jungha...@mailbox.org> wrote:
> > Hi Giacomo,
> >
> > I ran into the same issue. Seems to be coupled to the serialization
> mechanism of UDFs. I solved it by letting the base class implement the UDF
> interface (e.g. FlatMapFunction) and in addition make it generic (which
> should be necessary in your example).
> >
> > public [abstract] class CullTimeBase<IN, OUT> implements
> FlatMapFunction<IN, OUT> {
> > // ...
> > }
> >
> > public class CullTimeRainFall extends CullTimeBase<RainFallPOJO,
> RainFallPOJO> {
> > // ...
> > }
> >
> > This should work.
> >
> > Best,
> > Martin
> >
> >
> > On 16.09.2015 10:41, Giacomo Licari wrote:
> >> Hi guys,
> >> I'm trying to create a base class which is inherited from classes
> implementing FlatMap method on specific POJO types.
> >>
> >> It seems inheritance doesn't work, I can access this.PropertyName or
> super.PropertyName from flatMap method but values are always null.
> >>
> >> Here the derived class, using RainfallPOJO:
> >>
> >> public class CullTimeRainfall extends CullTimeBase implements
> FlatMapFunction<RainfallPOJO, RainfallPOJO> {
> >>
> >> public CullTimeRainfall(int num, int den, String time_data_name,
> String start_time, String end_time, int interval, String time_unit){
> >> super(num, den, time_data_name, start_time, end_time,
> interval, time_unit);
> >> }
> >>
> >> public void flatMap(RainfallPOJO obj, Collector<RainfallPOJO>
> coll) throws Exception {
> >> DateFormat formatter = new
> SimpleDateFormat("yyyy-MM-dd'T'hh:mm:ss.SSS");
> >> try {
> >> Date time = formatter.parse( obj.getTime().replaceAll(
> "([0-9\\-T]+:[0-9]{2}:[0-9.+]+):([0-9]{2})", "$1$2" ) );
> >> if(time.after(this.startTime) &&
> time.before(this.endTime)){
> >> coll.collect(obj);
> >> }
> >> } catch(Exception e){
> >> e.printStackTrace();
> >> }
> >> }
> >>
> >> }
> >>
> >> My Base class is:
> >>
> >> public class CullTimeBase {
> >>
> >> protected int numerator;
> >> protected int denominator;
> >> protected String timeDataName;
> >> protected Date startTime;
> >> protected Date endTime;
> >> protected int interval;
> >> protected String timeUnit;
> >>
> >> public CullTimeBase(int num, int den, String time_data_name,
> String start_time, String end_time, int interv, String time_unit){
> >> numerator = num;
> >> denominator = den;
> >> timeDataName = time_data_name;
> >> interval = interv;
> >> timeUnit = time_unit;
> >> DateFormat formatter = new
> SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
> >> try {
> >> startTime = formatter.parse(start_time);
> >> endTime = formatter.parse(end_time);
> >> } catch (ParseException e) {
> >> e.printStackTrace();
> >> }
> >> }
> >>
> >> It works only if I declare all variables and methods in only one class,
> but so I should repeat the same properties in more classes. I would only
> specialize each derived class with a custom flatMap method. which uses a
> custom POJO type.
> >>
> >> Thanks a lot,
> >> Giacomo
> >
> >
> >
> >
> >
>
>
>
>
