private FileEntriesLayer findNatives()

in arthur-maven-plugin/src/main/java/org/apache/geronimo/arthur/maven/mojo/JibMojo.java [465:515]
51 lines of code
14 McCabe index (conditional complexity)

    private FileEntriesLayer findNatives() {
        final Path home = findHome();
        getLog().info("Using natives from '" + home + "'");
        final Path jreLib = home.resolve("jre/lib");
        final boolean isWin = Files.exists(jreLib.resolve("java.lib"));
        Path nativeFolder = isWin ?
                jreLib /* win/cygwin */ :
                jreLib.resolve(System.getProperty("os.arch", "amd64")); // older graalvm, for 20.x it is no more needed
        if (!Files.exists(nativeFolder)) {
            nativeFolder = nativeFolder.getParent();
            try {
                if (!Files.exists(nativeFolder) || !Files.list(nativeFolder).anyMatch(it -> it.getFileName().toString().endsWith(".so"))) {
                    nativeFolder = home.resolve("lib");
                    if (!Files.exists(nativeFolder)) { // java 17 and after
                        throw new IllegalArgumentException("No native folder '" + nativeFolder + "' found.");
                    }
                }
            } catch (final IOException e) {
                throw new IllegalStateException(e);
            }
        }
        final boolean includeAll = singletonList("true").equals(includeNatives) || singletonList("*").equals(includeNatives);
        final Predicate<Path> include = includeAll ?
                p -> true : path -> {
            final String name = path.getFileName().toString();
            return includeNatives.stream().anyMatch(n -> name.contains(isWin ? (n + ".lib") : ("lib" + n + ".so")));
        };
        final FileEntriesLayer.Builder builder = FileEntriesLayer.builder();
        final Collection<String> collected = new ArrayList<>();
        final Path nativeDir = nativeFolder; // ref for lambda
        try {
            Files.walkFileTree(nativeFolder, new SimpleFileVisitor<Path>() {
                @Override
                public FileVisitResult visitFile(final Path file, final BasicFileAttributes attrs) throws IOException {
                    if (include.test(file)) {
                        collected.add(file.getFileName().toString());
                        builder.addEntry(
                                file, AbsoluteUnixPath.get(nativeRootDir).resolve(nativeDir.relativize(file).toString()),
                                FilePermissions.DEFAULT_FILE_PERMISSIONS, getTimestamp(file));
                    }
                    return super.visitFile(file, attrs);
                }
            });
        } catch (final IOException e) {
            throw new IllegalStateException(e);
        }
        if (!includeAll && collected.size() != includeNatives.size()) {
            throw new IllegalArgumentException("Found " + collected + " but was configured to extract " + includeNatives);
        }
        return builder.setName("Natives").build();
    }