Hi Chiwan Park, Thank you for the clarification
Regards, Rajesh On Sun, Jul 19, 2015 at 11:49 PM, Chiwan Park <chiwanp...@apache.org> wrote: > Hi, > > Flink program should have at least one data sink. When your program calls > `print` method, the method adds a data sink into your program automatically > and execute it immediately. If you want to run Flink program without > calling `print` method, you should add a data sink into your program and > execute it manually by calling `execute` method of `ExecutionEnvironment` > object. > > Note that only some methods about data sink such as `print`, `count` and > `collect` execute the program immediately. > > There are more detail descriptions about data sink [1] and lazy evaluation > [2] in Flink documentation. The documentation will help you to understand > the structure of Flink program. > > Regards, > Chiwan Park > > [1] > https://ci.apache.org/projects/flink/flink-docs-release-0.9/apis/programming_guide.html#data-sinks > [2] > https://ci.apache.org/projects/flink/flink-docs-release-0.9/apis/programming_guide.html#lazy-evaluation > > > On Jul 20, 2015, at 2:59 AM, Madabhattula Rajesh Kumar < > mrajaf...@gmail.com> wrote: > > > > Hi Scahin, > > > > Thank you for the response. I have commented counts print line. After > that I got below exception > > > > Exception in thread "main" java.lang.RuntimeException: No data sinks > have been created yet. A program needs at least one sink that consumes > data. Examples are writing the data set or printing it. > > at > org.apache.flink.api.java.ExecutionEnvironment.createProgramPlan(ExecutionEnvironment.java:914) > > at > org.apache.flink.api.java.ExecutionEnvironment.createProgramPlan(ExecutionEnvironment.java:893) > > at > org.apache.flink.api.java.LocalEnvironment.execute(LocalEnvironment.java:50) > > at > org.apache.flink.api.scala.ExecutionEnvironment.execute(ExecutionEnvironment.scala:590) > > at WordCount$.main(WordCount.scala:13) > > at WordCount.main(WordCount.scala) > > > > Regards, > > Rajesh > > > > On Sun, Jul 19, 2015 at 8:26 PM, Sachin Goel <sachingoel0...@gmail.com> > wrote: > > Hi > > You do not need to call env.execute after doing a print call. Print > itself triggers the execution. The reason for the Exception is quite > obvious. After the print call, there is no sink for the program execution. > So, execution cannot proceed. > > You can however explicitly define a sink and then call env.execute. > > > > Cheers! > > Sachin > > > > -- Sachin Goel > > Computer Science, IIT Delhi > > m. +91-9871457685 > > > > On Sun, Jul 19, 2015 at 8:06 PM, Madabhattula Rajesh Kumar < > mrajaf...@gmail.com> wrote: > > Hi, > > > > I have written simple wordcount program in scala. When I execute the > program, I'm getting below exception. > > > > Please let me know how to fix this issue. I'm using Flink 0.9.0 version > > > > Below is the program :- > > > > val env = ExecutionEnvironment.getExecutionEnvironment > > // get input data > > val text = env readTextFile("/Users/hadoop2/Data/word.txt") > > val counts = text flatMap(l=>l split(" ")) map(word=>(word,1)) > groupBy(0) sum(1) > > // emit result > > counts print > > env.execute("TEST") > > > > Exception :- > > > > Exception in thread "main" java.lang.RuntimeException: No new data sinks > have been defined since the last execution. The last execution refers to > the latest call to 'execute()', 'count()', 'collect()', or 'print()'. > > at > org.apache.flink.api.java.ExecutionEnvironment.createProgramPlan(ExecutionEnvironment.java:910) > > at > org.apache.flink.api.java.ExecutionEnvironment.createProgramPlan(ExecutionEnvironment.java:893) > > at > org.apache.flink.api.java.LocalEnvironment.execute(LocalEnvironment.java:50) > > at > org.apache.flink.api.scala.ExecutionEnvironment.execute(ExecutionEnvironment.scala:590) > > at WordCount$.main(WordCount.scala:17) > > at WordCount.main(WordCount.scala) > > > > Regards, > > Rajesh > > > > > > > > > >
