JDK 11.0.2 compilation fails with javac NPE on anonymous parameterized class type inference

Question

Code (spring-web 5.1.2)

public static void main(String[] args) {
    RestTemplate restTemplate = new RestTemplate();

    HttpHeaders headers = new HttpHeaders();
    headers.set(HttpHeaders.AUTHORIZATION, "token");
    HttpEntity<Object> requestEntity = new HttpEntity<>(headers);

    ResponseEntity<Object> test = restTemplate.exchange(
            "https://example.com",
            HttpMethod.GET,
            new HttpEntity<>(headers),
            new ParameterizedTypeReference<>() { // fails here
            });
}

OracleJDK 1.8 (expected output)

cannot infer type arguments for org.springframework.core.ParameterizedTypeReference

reason: cannot use '<>' with anonymous inner classes

OracleJDK 11.0.2 (not expected output)

compiler message file broken: key=compiler.misc.msg.bug arguments=11.0.2, {1}, {2}, {3}, {4}, {5}, {6}, {7} java.lang.NullPointerException at jdk.compiler/com.sun.tools.javac.comp.Flow$FlowAnalyzer.visitApply(Flow.java:1235) at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1634) at jdk.compiler/com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49) at jdk.compiler/com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:398) at jdk.compiler/com.sun.tools.javac.comp.Flow$FlowAnalyzer.visitVarDef(Flow.java:989)
...

If I change diamond operator to explicit type

new ParameterizedTypeReference<>(){} to new ParameterizedTypeReference<Object>(){}

then the code compiles successfully on both JDKs.

Is it a known compiler bug?

An exception from the compiler is a bug. Write up a test case and submit the bug. — Thorbjørn Ravn Andersen, Feb 19 '19 at 22:07
I am not able to build the project while my other team mates are able to build it . I tried to delete my repo . no luck . — Robert Ravikumar, Nov 16 '20 at 02:03
This is a bug in any version older than 11.0.8. Try upgrading your JDK to 11.0.8 or newer — Callum Atwal, Jan 27 '22 at 14:53

Mikhail Kholodkov · Accepted Answer · 2019-03-25T22:45:46.363

64

Bug (JDK-8212586) has been already submitted and fixed in version 12.

Minimal, verifiable example:

public static void main(String[] args) {
    new Bug<>(){};
}

static class Bug<T> {

    Bug() {
        test(new ParameterizedTypeReference<>(){});
    }

    void test(ParameterizedTypeReference<T> typeReference) {
    }
}

Some Details.

Fix has been also backported to JDK 11 - https://bugs.openjdk.java.net/browse/JDK-8220578.

Available starting JDK 11.0.4.

edited Mar 25 '19 at 22:45

answered Feb 19 '19 at 23:38

Mikhail Kholodkov

23,642
17
61
78

1

Does "fixed in version 12" mean that I need to install JDK 12 to get the fix? Will JDK 11 remain broken? – Troy Daniels Feb 25 '19 at 22:59
@TroyDaniels yes fix is included and scheduled to be released as part of JDK 12. https://openjdk.java.net/projects/jdk/12/ – Mikhail Kholodkov Feb 26 '19 at 16:46
what about JDK11 which "supposed" to be LTE? – Mircea Stanciu Mar 25 '19 at 20:44
2

@MirceaStanciu [fix has been backported](https://bugs.openjdk.java.net/browse/JDK-8220578) and will be available in JDK 11.0.4. Updated the answer. – Mikhail Kholodkov Mar 25 '19 at 22:43
3

java 11.0.6 has the same problem – Maxim Kasyanov Jun 29 '20 at 12:21
1

Some consusion about versions: in openjdk it is fixed 11.0.4 onwards, oracle jdk 11.0.8. See original bug report [link](https://bugs.openjdk.java.net/browse/JDK-8210197). – wdk Jan 15 '21 at 20:03
thanks this post saved me,was unable to figure out wats wrong,literally no stack trace pointing to this change – Anand Nov 30 '22 at 11:57

score 10 · Answer 2 · answered Jul 09 '20 at 11:54

10

As pointed out in previous comments, the problem is with parametrized anonymous classes, e.g. when using TypeToken from Guava, this does NOT work:

public List<SomeClass> list() {
    return getData(new TypeToken<>() { });
}

But this DOES work:

public List<SomeClass> list() {
    return getData(new TypeToken<List<SomeClass>>() { });
}

I tried that in versions 11.0.3 - 11.0.7 versions and all contains the bug.

answered Jul 09 '20 at 11:54

Miri

105
1
3

OpenJDK 11.0.8 has the bug too – aksh1618 Jan 05 '21 at 14:47
I did with 11.0.12 and it works. – KnockingHeads Dec 12 '22 at 06:21

score 9 · Answer 3 · edited Sep 21 '19 at 04:33

9

I Had the same error,you need to create a function :

ParameterizedTypeReference<Object> createParameterizedTypeReference(){ return new ParameterizedTypeReference<>(){}; }

and call it :

ResponseEntity<Object> test = restTemplate.exchange(
"https://example.com",
HttpMethod.GET,
new HttpEntity<>(headers),
createParameterizedTypeReference() { 
});

edited Sep 21 '19 at 04:33

Michael

2,189
16
23

answered Jun 25 '19 at 08:37

Otmane el alami el hassani

91
1
1

score 4 · Answer 4 · edited Jun 30 '20 at 08:27

4

Java 11.0.7 has the same problem.

This changed from:

new ParameterizedTypeReference<>() {
})

to this:

new ParameterizedTypeReference<HashMap<String, MyClass>>() {
})

edited Jun 30 '20 at 08:27

Václav

990
1
12
28

answered Jun 30 '20 at 08:02

Martin Langvatn

41
3

score 2 · Answer 5 · answered Aug 10 '20 at 12:30

2

I've fixed this problem on my machine by upgrading to AdoptOpenJDK 11.0.8.

https://adoptopenjdk.net/installation.html#x64_mac-jdk

answered Aug 10 '20 at 12:30

bogdancep

208
2
4

score 0 · Answer 6 · answered Oct 14 '22 at 09:41

0

Most of the times, this error doesn't tell you the originating class so it's very hard to intentionally reproduce the problem. After trying a lot, I finally updated project JDK to 11.0.16 (from 11.0.7) and it worked!

answered Oct 14 '22 at 09:41

Ashutosh Srivastav

649
7
11

score 0 · Answer 7 · answered Jun 13 '23 at 21:43

0

In case anyone else faces this issue: we had to change the java compiler from javac to eclipse (anything else that's not javac) to get our code to compile. Upgrading/downgrading jdk didn't fix the issue for us.

answered Jun 13 '23 at 21:43

Naveen LP

61
2

JDK 11.0.2 compilation fails with javac NPE on anonymous parameterized class type inference

7 Answers7

Linked