Attachment 274049 Details for Bug 534712 – Source file to reproduce the problem

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Source file to reproduce the problem

TestBadGenerics.java (text/plain), 1.97 KB, created by Christian Connert

on 2018-05-15 11:48:59 EDT

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Creator: Christian Connert

Created: 2018-05-15 11:48:59 EDT

Size: 1.97 KB

patch

obsolete

>package at.arz.eb01a.faq.service.impl;
>
>import java.lang.reflect.Method;
>import java.util.Arrays;
>import java.util.Collection;
>import java.util.List;
>import java.util.Optional;
>import java.util.stream.Collectors;
>
>@SuppressWarnings("unused")
>public class TestBadGenerics {
>	
>   /*
>	* private java.util.Optional at.arz.eb01a.faq.service.impl.TestBadGenerics.lambda$6(at.arz.eb01a.faq.service.impl.TestBadGenerics)
>	* [null]
>	* [class at.arz.eb01a.faq.service.impl.TestBadGenerics]
>	*/
>	private <T extends TestBadGenerics> List<T> getFilteredEntriesBad(final Collection<T> source) {
>		return source	.stream()
>						.map(this::getFilteredEntry)  
>						.filter(Optional::isPresent)
>						.map(Optional::get)
>						.collect(Collectors.toList());		 	
>	}
>	
>	// Using a method reference (this::getFilteredEntry) does case a NPE with eclipse oxygen 3a because of invalid generic types information in class file
>   /*
>	* private java.util.Optional at.arz.eb01a.faq.service.impl.TestBadGenerics.lambda$3(at.arz.eb01a.faq.service.impl.TestBadGenerics)
>	* [class at.arz.eb01a.faq.service.impl.TestBadGenerics]
>	* [class at.arz.eb01a.faq.service.impl.TestBadGenerics]
>	*/
>	private <T extends TestBadGenerics> List<T> getFilteredEntriesOk(final Collection<T> source) {
>		return source	.stream()
>						.map(e -> getFilteredEntry(e))  
>						.filter(Optional::isPresent)
>						.map(Optional::get)
>						.collect(Collectors.toList());		 	
>	}
>
>	private <T extends TestBadGenerics> Optional<T> getFilteredEntry(final Optional<T> source) {
>		return getFilteredEntry(source.orElse(null));
>	}
>
>	private <T extends TestBadGenerics> Optional<T> getFilteredEntry(final T source) {
>		return Optional.empty();
>	}
>
>	
>	public static void main(String[] args) {
>		for(Method m : TestBadGenerics.class.getDeclaredMethods()) {
>			System.err.println(m);
>			System.err.println(Arrays.asList(m.getGenericParameterTypes()));
>			System.err.println(Arrays.asList(m.getParameterTypes()));
>		}
>	}
>	
>}

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Attachments on bug 534712: 274049 | 274051