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fwiw, this compile from at least JDK 11 onwards:</div>
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import java.util.*;
<div class="ContentPasted0">import java.util.stream.*;</div>
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<div class="ContentPasted0">public class TDotToString {</div>
<div class="ContentPasted0"> class Bar {</div>
<div class="ContentPasted0"> private String asString() {</div>
<div class="ContentPasted0"> return "bar";</div>
<div class="ContentPasted0"> }</div>
<div class="ContentPasted0"> }</div>
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<div class="ContentPasted0"> static <T extends Bar> String foo(List<T> list) {</div>
<div class="ContentPasted0"> return list.stream().map(T::asString).collect(Collectors.joining());</div>
<div class="ContentPasted0"> }</div>
}<br>
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javac from 1.8.0 does issue error as mentioned by Remi.</div>
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-Sundar</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> compiler-dev <compiler-dev-retn@openjdk.org> on behalf of Remi Forax <forax@univ-mlv.fr><br>
<b>Sent:</b> 16 October 2023 13:57<br>
<b>To:</b> compiler-dev <compiler-dev@openjdk.org><br>
<b>Subject:</b> Regression: accessing a private method through a type variable</font>
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<div class="PlainText">Hello,<br>
There is a regression in recent versions of javac.<br>
javac 21 allows to access a private method through a type variable, here T::asString.<br>
<br>
public class TDotToString {<br>
class Bar() {<br>
private String asString() {<br>
return "bar";<br>
}<br>
}<br>
<br>
static <T extends Bar> String foo(List<T> list) {<br>
return list.stream().map(T::asString).collect(Collectors.joining());<br>
}<br>
}<br>
<br>
Both IntelliJ and Eclipse emit an error in this case.<br>
<br>
And javac 8 emits<br>
TDotToString.java:12: error: invalid method reference<br>
return list.stream().map(T::asString).collect(Collectors.joining());<br>
^<br>
cannot find symbol<br>
symbol: method asString()<br>
location: bound of type variable T<br>
where T is a type-variable:<br>
T extends TDotToString.Bar declared in method <T>foo(List<T>)<br>
1 error<br>
<br>
regards,<br>
Rémi<br>
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