[英]How to read file from src/main/resources with annotation processor?
I have a simple annotation processor that needs to read a configuration file from the same project as the annotated classes.我有一个简单的注释处理器,它需要从与注释类相同的项目中读取配置文件。 Example structure:
示例结构:
- myproject
- src
- main
- java
- my.package.SourceFile
- resources
- config.json
In the annotation processor, I try to read the file:在注释处理器中,我尝试读取文件:
FileObject resource = processingEnv.getFiler().getResource(StandardLocation.SOURCE_PATH, "", "config.json");
but it throws FileNotFoundException
.但它抛出
FileNotFoundException
。 I also tried other paths, such as ../resources/config.json
, (which throws Invalid relative name: ../resources/config.json
).我还尝试了其他路径,例如
../resources/config.json
,(这会抛出Invalid relative name: ../resources/config.json
)。 And I tried putting the config file in src/main/java
(and even src/main/java/my/package
) instead, which I don't like, but that also still throws FileNotFoundException
.我尝试将配置文件放在
src/main/java
(甚至是src/main/java/my/package
)中,我不喜欢,但这仍然会抛出FileNotFoundException
。
It would already help if I could get filer.getResource()
to tell me where it's looking.如果我能让
filer.getResource()
告诉我它在哪里,那已经filer.getResource()
。 To find that out, I tried generating a file:为了找出答案,我尝试生成一个文件:
filer.createResource(StandardLocation.SOURCE_OUTPUT, "", "dummy");
which generated in myproject/build/classes/main/dummy
.在
myproject/build/classes/main/dummy
。 Unfortunately, I can't generate in SOURCE_PATH
, so that doesn't help with finding this out.不幸的是,我无法在
SOURCE_PATH
生成,因此这无助于发现这一点。
I'd expect that the stuff from src/main/resources
gets copied to target/classes
during the build (prior to annotation processing).我希望来自
src/main/resources
在构建期间(在注释处理之前)被复制到target/classes
。 In that case you can open them like this:在这种情况下,您可以像这样打开它们:
ProcessingEnvironment pe = ...;
FileObject fileObject = pe.getFiler()
.getResource( StandardLocation.CLASS_OUTPUT, "", "config.json" );
InputStream jsonStream = fileObject.openInputStream();
I've looked at this with one of the Project Lombok developers.我已经与 Project Lombok 的一位开发人员一起研究过这个问题。 If anyone knows annotation processing, it's them ;)
如果有人知道注释处理,那就是他们;)
Our conclusion was, that the JavacFileManager
that handles the request internally, does not have a path to resolve StandardLocation.SOURCE_PATH
to.我们的结论是,在内部处理请求的
JavacFileManager
没有将StandardLocation.SOURCE_PATH
解析为的路径。 We're not sure, but it might be related to building with Gradle.我们不确定,但这可能与使用 Gradle 构建有关。
I had the same problem and was searching for solution for a while and found this cool hack that does the trick for Android我遇到了同样的问题,正在寻找解决方案一段时间,发现这个很酷的 hack对 Android 有用
And below you can see my solution from pure Java/Kotlin project在下面你可以从纯 Java/Kotlin 项目中看到我的解决方案
fun ProcessingEnvironment.getResourcesDirectory(): File {
val dummySourceFile = filer.createSourceFile("dummy" + System.currentTimeMillis())
var dummySourceFilePath = dummySourceFile.toUri().toString()
if (dummySourceFilePath.startsWith("file:")) {
if (!dummySourceFilePath.startsWith("file://")) {
dummySourceFilePath = "file://" + dummySourceFilePath.substring("file:".length)
}
} else {
dummySourceFilePath = "file://$dummySourceFilePath"
}
val cleanURI = URI(dummySourceFilePath)
val dummyFile = File(cleanURI)
val projectRoot = dummyFile.parentFile.parentFile.parentFile.parentFile.parentFile
return File(projectRoot.absolutePath + "/resources")
}
Following function works for me with annotation processor being triggered by gradle, it's not the pretties one but works:以下功能适用于我,由 gradle 触发注释处理器,它不是漂亮的,但有效:
private fun resolveApplicationPropertiesFile(): File {
val projectRoot = Path.of(processingEnv.filer.getResource(StandardLocation.CLASS_OUTPUT, "", "doesntmatter")
.toUri())
.parent
.parent
.parent
.parent
.parent
.parent
val properties = Path.of(projectRoot.toString(), "src", "main", "resources", "application.yml")
return properties.toFile()
}
where processingEnv
is a member of AbstractProcessor
其中
processingEnv
是AbstractProcessor
的成员
If your element is instance of TypeElement
,then you can use these code to find your source code如果您的元素是
TypeElement
实例,那么您可以使用这些代码来查找源代码
FileObject fileObject = processingEnv.getFiler().getResource( StandardLocation.SOURCE_PATH, element.getEnclosingElement().toString(), element.getSimpleName() + ".java");
element.getEnclosingElement()
is your class package, eg: com.fool element.getEnclosingElement()
是你的类包,例如:com.foolelement.getSimpleName()
is your class name, eg: Person element.getSimpleName()
是你的类名,例如:Person then you can print them: CharSequence content = fileObject.getCharContent(true);
然后你可以打印它们:
CharSequence content = fileObject.getCharContent(true);
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.