[
https://issues.apache.org/jira/browse/FLINK-4793?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Timo Walther reassigned FLINK-4793:
-----------------------------------
Assignee: Timo Walther
> Using a local method with :: notation in Java 8 causes index out of bounds
> --------------------------------------------------------------------------
>
> Key: FLINK-4793
> URL: https://issues.apache.org/jira/browse/FLINK-4793
> Project: Flink
> Issue Type: Bug
> Reporter: Ted Dunning
> Assignee: Timo Walther
>
> I tried to use the toString method on an object as a map function:
> {code}
> .<String>map(Trade::toString)
> {code}
> This caused an index out of bounds error:
> {code}
> java.lang.ArrayIndexOutOfBoundsException: -1
> at
> org.apache.flink.api.java.typeutils.TypeExtractor.getUnaryOperatorReturnType(TypeExtractor.java:351)
> at
> org.apache.flink.api.java.typeutils.TypeExtractor.getUnaryOperatorReturnType(TypeExtractor.java:305)
> at
> org.apache.flink.api.java.typeutils.TypeExtractor.getMapReturnTypes(TypeExtractor.java:120)
> at
> org.apache.flink.streaming.api.datastream.DataStream.map(DataStream.java:506)
> at
> com.mapr.aggregate.AggregateTest.testAggregateTrades(AggregateTest.java:81)
> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> at
> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
> at
> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> at
> org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
> at
> org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
> at
> org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
> at
> org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
> at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
> at
> org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
> at
> org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
> at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
> at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
> at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
> at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
> at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
> at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
> at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
> at
> com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
> {code}
> On the other hand, if I use a public static method, like this:
> {code}
> .<Trade>map(Trade::fromString)
> {code}
> All is good. fromString and toString are defined like this:
> {code}
> public static Trade fromString(String s) throws IOException {
> return mapper.readValue(s, Trade.class);
> }
> @Override
> public String toString() {
> return String.format("{\"%s\", %d, %d, %.2f}", symbol, time, volume,
> price);
> }
> {code}
> This might be a viable restriction on what functions I can use, but there
> certainly should be a better error message, if so.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
