偏食外空注释为java.lang.Object继承＃的getClass（） [英] Eclipse external null annotation for java.lang.Object#getClass()
问题描述
我使用Eclipse中提供火星外空注释设施。我想添加一个外部注释为的java.lang.Object＃的getClass（），但似乎无法得到签名的权利。我试过以下变化：
I'm using the external null annotation facility available in Eclipse Mars. I'm trying to add an external annotation for java.lang.Object#getClass() but can't seem to get the signature right. I've tried the following variations:
@NonNull Class<?> getClass() [()L1java/lang/Class<*>;]
@NonNull Class<@NonNull ?> getClass() [()L1java/lang/Class<*1>;]
但继续获得通过调用的getClass（）来接受类和LT的实例的方法的结果时警告;？＆GT; ，其中的参数被注解为 @NonNull 。
but continue to get a warning when passing the result of invoking getClass() to a method that accepts an instance of Class<?>, where that parameter is annotated with @NonNull.
以下是重现该问题最小的Eclipse项目的火星相关的文件（本例中使用的第一个空注释的变化之上，但使用第二个变化时，我也得到了同样的警告）：
Below are the relevant files from a minimal Eclipse Mars project that reproduces the issue (this example uses the first null annotation variation above, but I also get the same warning when using the second variation):
的火星的Eclipse版本（4.5.0; 20150621-1200）用于Windows 64位的结果
的Oracle JDK 1.8.0_60 的
的src /酒吧/ Foo.java
package bar;
public class Foo {
private static void printType(Class<?> type) {
System.out.println(type.getName());
}
public static void main(String[] args) {
Foo foo = new Foo();
printType(foo.getClass());
}
}
的src /酒吧/ package-info.java
@org.eclipse.jdt.annotation.NonNullByDefault
package bar;
注释/ JAVA / LANG / Object.eea
class java/lang/Object
getClass
()Ljava/lang/Class<*>;
()L1java/lang/Class<*>;
.settings / org.eclipse.jdt.core。preFS （部分）
eclipse.preferences.version=1
org.eclipse.jdt.core.compiler.annotation.inheritNullAnnotations=enabled
org.eclipse.jdt.core.compiler.annotation.missingNonNullByDefaultAnnotation=warning
org.eclipse.jdt.core.compiler.annotation.nonnull=org.eclipse.jdt.annotation.NonNull
org.eclipse.jdt.core.compiler.annotation.nonnullbydefault=org.eclipse.jdt.annotation.NonNullByDefault
org.eclipse.jdt.core.compiler.annotation.nullable=org.eclipse.jdt.annotation.Nullable
org.eclipse.jdt.core.compiler.annotation.nullanalysis=enabled
...
org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.8
...
org.eclipse.jdt.core.compiler.compliance=1.8
...
org.eclipse.jdt.core.compiler.problem.includeNullInfoFromAsserts=enabled
...
org.eclipse.jdt.core.compiler.problem.nonnullParameterAnnotationDropped=warning
org.eclipse.jdt.core.compiler.problem.nullAnnotationInferenceConflict=error
org.eclipse.jdt.core.compiler.problem.nullReference=error
org.eclipse.jdt.core.compiler.problem.nullSpecViolation=error
org.eclipse.jdt.core.compiler.problem.nullUncheckedConversion=warning
...
org.eclipse.jdt.core.compiler.problem.potentialNullReference=error
...
org.eclipse.jdt.core.compiler.problem.redundantNullAnnotation=warning
org.eclipse.jdt.core.compiler.problem.redundantNullCheck=warning
...
org.eclipse.jdt.core.compiler.problem.syntacticNullAnalysisForFields=enabled
...
org.eclipse.jdt.core.compiler.source=1.8
的.classpath
<?xml version="1.0" encoding="UTF-8"?>
<classpath>
<classpathentry kind="src" path="src"/>
<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8">
<attributes>
<attribute name="annotationpath" value="/null-annotation-test/annotations"/>
</attributes>
</classpathentry>
<classpathentry kind="lib" path="org.eclipse.jdt.annotation_2.0.100.v20150311-1658.jar"/>
<classpathentry kind="output" path="bin"/>
</classpath>
有关上述项目，我收到的第10行以下警告的 Foo.java 的（其中平面广告类型叫）：
For the above project, I receive the following warning on line 10 of Foo.java (where printType is called):
Null type safety (type annotations): The expression of type 'Class<capture#of ? extends Foo>' needs unchecked conversion to conform to '@NonNull Class<?>'
这是同样的警告，我得到不对外空注解是present。
which is the same warning I get without the external null annotation being present.
我如何正确地创建了的java.lang.Object＃的getClass外空注释（）删除此警告？或者是我在平面广告类型？
How do I correctly create an external null annotation for java.lang.Object#getClass() to remove this warning? Or is my problem in the declaration of printType?
推荐答案
路易·瑟曼是正确的，在类型检查方面不存在的有一个的的getClass（）方法，但每个类都有它自己专门的签名方法。因此，在一个.eea文件没有签名都不会匹配实际的getClass（）方法。
Louis Wasserman is correct, in terms of type checking there is not one getClass() method, but each class has it's own method with specialized signature. Hence no signature in a .eea file will ever match the actual getClass() methods.
我提交了 RFE 投入约<$更多的专业知识C $ C>的getClass（）入编译器，这样，所需的此兽没有外部的注释。
I filed an RFE to put more special knowledge about getClass() into the compiler, so that no external annotations are needed for this beast.
编辑：：此功能已经实现，并会与Eclipse 4.6（霓虹灯）公布
This feature has been implemented and will be released with Eclipse 4.6 (Neon).
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