我希望使我的代码更具可读性,以及使用工具,如IDE代码检查和/或静态代码分析(FindBugs和Sonar),以避免nullpointerexception。许多工具似乎与彼此的@NotNull/@NonNull/ @NonNull注释不兼容,在我的代码中列出所有这些工具会让人难以阅读。有没有什么建议,哪一个是“最好的”?下面是我找到的等价注释列表:

javax.validation.constraints.NotNull Created for runtime validation, not static analysis. documentation edu.umd.cs.findbugs.annotations.NonNull Used by FindBugs (dead project) and its successor SpotBugs static analysis and therefore Sonar (now Sonarqube) FindBugs documentation, SpotBugs documentation javax.annotation.Nonnull This might work with FindBugs too, but JSR-305 is inactive. (See also: What is the status of JSR 305?) source org.jetbrains.annotations.NotNull Used by IntelliJ IDEA IDE for static analysis. documentation lombok.NonNull Used to control code generation in Project Lombok. Placeholder annotation since there is no standard. source, documentation androidx.annotation.NonNull Marker annotation available in Android, provided by annotation package documentation org.eclipse.jdt.annotation.NonNull Used by Eclipse for static code analysis documentation


当前回答

One of the nice things about IntelliJ is that you don't need to use their annotations. You can write your own, or you can use those of whatever other tool you like. You're not even limited to a single type. If you're using two libraries that use different @NotNull annotations, you can tell IntelliJ to use both of them. To do this, go to "Configure Inspections", click on the "Constant Conditions & Exceptions" inspection, and hit the "Configure inspections" button. I use the Nullness Checker wherever I can, so I set up IntelliJ to use those annotations, but you can make it work with whatever other tool you want. (I have no opinion on the other tools because I've been using IntelliJ's inspections for years, and I love them.)

其他回答

安卓

这个答案是Android特有的。Android有一个支持包叫做support-annotations。它提供了几十个Android特定的注释,也提供了常见的注释,如NonNull, Nullable等。

要添加support-annotations包,在build.gradle中添加以下依赖项:

compile 'com.android.support:support-annotations:23.1.1'

然后使用:

import android.support.annotation.NonNull;

void foobar(@NonNull Foo bar) {}

JSpecify将是一种方法(当它准备好时)。事实上,他们的陈述积极地与这个问题联系在一起,并明确表示他们的目标是最终得到一个好的答案。

它拥有Android、Guava和Kotlin等主要参与者。

如果有人只是在寻找IntelliJ类:您可以从maven存储库中使用

<dependency>
    <groupId>org.jetbrains</groupId>
    <artifactId>annotations</artifactId>
    <version>15.0</version>
</dependency> 

对于Android项目,您应该使用Android .support.annotation. nonnull和Android .support.annotation. nullable。这些和其他有用的特定于android的注释在支持库中可用。

从http://tools.android.com/tech-docs/support-annotations:

支持库本身也使用这些注释 注解,所以作为支持库的用户,Android Studio将 检查您的代码并基于这些标记潜在的问题 注释。

我使用IntelliJ,因为我最关心的是IntelliJ标记可能产生NPE的东西。我同意在JDK中没有标准注释是令人沮丧的。有传言说要添加它,它可能会加入到Java 7中。这样的话,就多了一个选择!