You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@flink.apache.org by "ASF GitHub Bot (JIRA)" <ji...@apache.org> on 2015/08/07 09:42:45 UTC

[jira] [Commented] (FLINK-2495) Add a null point check in API DataStream.union

    [ https://issues.apache.org/jira/browse/FLINK-2495?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14661453#comment-14661453 ] 

ASF GitHub Bot commented on FLINK-2495:
---------------------------------------

GitHub user HuangWHWHW opened a pull request:

    https://github.com/apache/flink/pull/999

    [FLINK-2495][fix]Add a null point check in API DataStream.union

    The API(public DataStream<OUT> union(DataStream<OUT>... streams)) is a  external interface for user.
    The parameter "streams" maybe null and it will throw NullPointerException error.
    
    This test below can be intuitive to explain this problem:
    
    package org.apache.flink.streaming.api;
    
    import org.apache.flink.api.common.functions.MapFunction;
    import org.apache.flink.streaming.api.datastream.DataStream;
    import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
    import org.apache.flink.streaming.api.functions.source.RichParallelSourceFunction;
    import org.junit.Test;
    
    /**
     * Created by HuangWHWHW on 2015/8/7.
     */
    public class test {
    
    	public static class sourceFunction extends RichParallelSourceFunction<String> {
    
    		public sourceFunction() {
    		}
    
    		@Override
    		public void run(SourceContext<String> sourceContext) throws Exception {
    			sourceContext.collect("a");
    		}
    
    		@Override
    		public void cancel() {
    
    		}
    	}
    
    	@Test
    	public void testUnion(){
    		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
    		env.setParallelism(1);
    		DataStream<String> source = env.addSource(new sourceFunction());
    		DataStream<String> temp1 = null;
    		DataStream<String> temp2 = source.map(new MapFunction<String, String>() {
    			@Override
    			public String map(String value) throws Exception {
    				if (value == "a") {
    					return "This is for test temp2.";
    				}
    				return null;
    			}
    		});
    		DataStream<String> sink = temp2.union(temp1);
    		sink.print();
    		try {
    			env.execute();
    		}catch (Exception e){
    			e.printStackTrace();
    		}
    	}
    
    }


You can merge this pull request into a Git repository by running:

    $ git pull https://github.com/HuangWHWHW/flink FLINK-2495

Alternatively you can review and apply these changes as the patch at:

    https://github.com/apache/flink/pull/999.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

    This closes #999
    
----
commit 89b4aa6c94e4e00ec382746e41ae893d83b55d86
Author: HuangWHWHW <40...@qq.com>
Date:   2015-08-07T07:38:21Z

    [FLINK-2495][fix]Add a null point check in API DataStream.union

----


> Add a null point check in API DataStream.union
> ----------------------------------------------
>
>                 Key: FLINK-2495
>                 URL: https://issues.apache.org/jira/browse/FLINK-2495
>             Project: Flink
>          Issue Type: Bug
>          Components: Streaming
>    Affects Versions: 0.10
>            Reporter: Huang Wei
>             Fix For: 0.10
>
>   Original Estimate: 168h
>  Remaining Estimate: 168h
>
> The API(public DataStream<OUT> union(DataStream<OUT>... streams)) is a  external interface for user.
> The parameter "streams" maybe null and it will throw NullPointerException error.
> This test below can be intuitive to explain this problem:
> package org.apache.flink.streaming.api;
> import org.apache.flink.api.common.functions.MapFunction;
> import org.apache.flink.streaming.api.datastream.DataStream;
> import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
> import org.apache.flink.streaming.api.functions.source.RichParallelSourceFunction;
> import org.junit.Test;
> /**
>  * Created by HuangWHWHW on 2015/8/7.
>  */
> public class test {
> 	public static class sourceFunction extends RichParallelSourceFunction<String> {
> 		public sourceFunction() {
> 		}
> 		@Override
> 		public void run(SourceContext<String> sourceContext) throws Exception {
> 			sourceContext.collect("a");
> 		}
> 		@Override
> 		public void cancel() {
> 		}
> 	}
> 	@Test
> 	public void testUnion(){
> 		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
> 		env.setParallelism(1);
> 		DataStream<String> source = env.addSource(new sourceFunction());
> 		DataStream<String> temp1 = null;
> 		DataStream<String> temp2 = source.map(new MapFunction<String, String>() {
> 			@Override
> 			public String map(String value) throws Exception {
> 				if (value == "a") {
> 					return "This is for test temp2.";
> 				}
> 				return null;
> 			}
> 		});
> 		DataStream<String> sink = temp2.union(temp1);
> 		sink.print();
> 		try {
> 			env.execute();
> 		}catch (Exception e){
> 			e.printStackTrace();
> 		}
> 	}
> }



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)