遇java.io.FileNotFoundException报错，文件存在却无法识别求助

Let’s break down why you’re hitting this error even though the file exists, and walk through fixes step by step:

Common Causes & Solutions #

1. Your JVM’s working directory isn’t what you expect #

When you use a relative path like "AuthKey_7RHM5B8NS7.p8", Java looks for the file relative to the JVM’s current working directory—not the folder where your code file is stored.

To confirm this, add a quick debug line to print the working directory:

System.out.println("Current JVM working directory: " + System.getProperty("user.dir"));

Run your code and check the output. If your auth key file isn’t in that directory, that’s the root issue.

2. Test with an absolute path (quick sanity check) #

As a temporary test, replace the relative path with the full absolute path to your file. For example:

new File("/Users/yourname/projects/yourapp/AuthKey_7RHM5B8NS7.p8")

If this works, you’ve confirmed the problem is with relative path resolution, not the file itself.

3. Load the file reliably (for Maven/Gradle projects) #

The best practice for project resources is to place your auth key in the src/main/resources folder. Then use the class loader to load it—this works no matter where your JVM is launched from:

final ApnsClient apnsClient = new ApnsClientBuilder()
    .setApnsServer(ApnsClientBuilder.DEVELOPMENT_APNS_HOST)
    .setSigningKey(ApnsSigningKey.loadFromPkcs8InputStream(
        getClass().getResourceAsStream("/AuthKey_7RHM5B8NS7.p8"),
        "GL87ZNESF6",
        "7RHM5B8NS7"
    ))
    .build();

4. Double-check permissions & case sensitivity #

• On Linux/macOS, ensure the file has read permissions for the user running your app. Run ls -l AuthKey_7RHM5B8NS7.p8 in terminal—you should see r in the permissions string (e.g., -rw-r--r--).
• Filenames are case-sensitive on Unix-like systems. Make sure your code’s filename matches exactly (no typos like authkey_7rhm5b8ns7.p8 instead of AuthKey_7RHM5B8NS7.p8).

5. Build the path dynamically (if the file stays in project root) #

If you need to keep the file in your project root instead of resources, build the path using the project directory:

Path keyFilePath = Paths.get(System.getProperty("user.dir"), "AuthKey_7RHM5B8NS7.p8");
final ApnsClient apnsClient = new ApnsClientBuilder()
    .setApnsServer(ApnsClientBuilder.DEVELOPMENT_APNS_HOST)
    .setSigningKey(ApnsSigningKey.loadFromPkcs8File(keyFilePath.toFile(), "GL87ZNESF6", "7RHM5B8NS7"))
    .build();

内容的提问来源于stack exchange，提问作者George