太阳现在没有自己的了吗?这是什么: http://www.java2s.com/Open-Source/Java-Document/6.0-JDK-Modules-com.sun/istack/com.sun.istack.internal.htm

这似乎与我在过去几年中使用过的所有Java版本都打包在一起。

编辑:正如下面评论中提到的，你可能不想使用这些。在这种情况下，我的投票是IntelliJ jetbrains注释!

如果您正在使用Spring 5。2.执行以下命令:你应该使用Spring注释(org.springframework.lang)，因为它们通过@NonNullFields和@NonNullApi注解为你提供了默认的包范围的null检查。当你使用@NonNullFields/@NonNullApi时，你甚至不会与来自其他依赖的其他NotNull/NonNull注释发生冲突。注释必须用在一个名为package-info.java的文件中，该文件位于包的根目录下:

@NonNullFields
@NonNullApi
package org.company.test;

要排除null检查中的某些字段、参数或返回值，只需显式地使用@Nullable注释。而不是使用@NonNullFields/@NonNullApi，你也可以在任何地方设置@NonNull，但可能更好的是在默认情况下使用@NonNullFields/@NonNullApi激活null检查，并且只使用@Nullable执行特定的异常。

IDE (Intellij)将突出显示违反null条件的代码。如果设置正确，每个开发人员都可以假设字段、参数和返回值必须不是空，除非有@Nullable注释。要了解更多信息，请查看这篇文章。

在等待上游(Java 8?)整理这些注释时，您还可以定义自己的项目本地@NotNull和@Nullable注释。这在使用Java SE时也很有用，因为默认情况下javax.validation.constraints是不可用的。

import java.lang.annotation.*;

/**
 * Designates that a field, return value, argument, or variable is
 * guaranteed to be non-null.
 */
@Target({ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER, ElementType.LOCAL_VARIABLE})
@Documented
@Retention(RetentionPolicy.CLASS)
public @interface NotNull {}

/**
 * Designates that a field, return value, argument, or variable may be null.
 */
@Target({ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER, ElementType.LOCAL_VARIABLE})
@Documented
@Retention(RetentionPolicy.CLASS)
public @interface Nullable {}

不可否认，这主要是为了装饰或未来的目的，因为上面显然没有为这些注释的静态分析增加任何支持。

不幸的是，JSR 308将不会添加比这个项目本地非空建议更多的值

Java 8将不会提供单一的默认注释或自己的Checker框架。 类似于Find-bugs或JSR 305，这个JSR由一小群主要是学术团队维护得很差。

它背后没有商业力量，因此JSR 308现在发布EDR 3 (JCP的早期草案审查)，而Java 8应该在不到6个月内发布:-O 顺便说一句，类似于310。但与308不同的是，Oracle现在已经从其创始人手中接管了这一业务，以最大限度地减少它对Java平台的伤害。

每个项目、供应商和学术类，比如检查器框架和JSR 308背后的那些，都将创建自己的专有检查器注释。

让源代码在未来几年不兼容，直到找到一些流行的妥协，并可能添加到Java 9或10中，或者通过Apache Commons或谷歌Guava这样的框架;-)

我非常喜欢检查器框架，它是类型注释(JSR-308)的实现，用于实现像null检查器这样的缺陷检查器。我并没有尝试其他任何方法进行比较，但我对这个实现感到满意。

我没有加入提供该软件的组织，但我是它的粉丝。

我喜欢这个系统的四个方面:

It has a defect checkers for nullness (@Nullable), but also has ones for immutability and interning (and others). I use the first one (nullness) and I'm trying to get into using the second one (immutability/IGJ). I'm trying out the third one, but I'm not certain about using it long term yet. I'm not convinced of the general usefulness of the other checkers yet, but its nice to know that the framework itself is a system for implementing a variety of additional annotations and checkers. The default setting for nullness checking works well: Non-null except locals (NNEL). Basically this means that by default the checker treats everyhing (instance variables, method parameters, generic types, etc) except local variables as if they have a @NonNull type by default. Per the documentation: The NNEL default leads to the smallest number of explicit annotations in your code. You can set a different default for a class or for a method if NNEL doesn't work for you. This framework allows you to use with without creating a dependency on the framework by enclosing your annotations in a comment: e.g. /*@Nullable*/. This is nice because you can annotate and check a library or shared code, but still be able to use that library/shared coded in another project that doesn't use the framework. This is a nice feature. I've grown accustom to using it, even though I tend to enable the Checker Framework on all my projects now. The framework has a way to annotate APIs you use that aren't already annotated for nullness by using stub files.

Another option is the annotations provided with ANTLR 4. Following Pull Request #434, the artifact containing the @NotNull and @Nullable annotations includes an annotation processor that produces compile-time errors and/or warnings in the event one of these attributes is misused (for example, if both are applied to the same item, or if @Nullable is applied to item with a primitive type). The annotation processor provides additional assurance during the software development process that the information conveyed by the application of these annotations is accurate, including in cases of method inheritance.