ClassNameExtractor

ClassNameExtractor.kt

class ClassNameExtractor() {  
    fun extractClasses() {  
        val prefixDir = "/Users/user/Sources/my/external/src/main/kotlin/"  
        val packages = getNestedDirectoryPaths(  
            "${prefixDir}dev/umbum/my/package",  
        )  
            .map { it.removePrefix(prefixDir).replace("/", ".") }  
            .filter { it.contains("dto") }  
            
        println(packages.joinToString("\n"))  
        println("---")
  
        packages  
            .flatMap { findAllClassesUsingClassLoader(it) }  
            .forEach { println(it) }  
    }  
  
    private fun findAllClassesUsingClassLoader(packageName: String): Set<Class<*>?> {  
        val stream = ClassLoader.getSystemClassLoader()  
            .getResourceAsStream(packageName.replace("[.]".toRegex(), "/")) ?: return emptySet()  
  
        val reader = BufferedReader(InputStreamReader(stream))  
        return reader.lines()  
            .filter { it.endsWith(".class") }  
            .map { getClass(it, packageName) }  
            .collect(Collectors.toSet())  
    }  
    
    private fun getClass(className: String, packageName: String): Class<*>? {  
        return Class.forName(  
            packageName + "." + className.substring(0, className.lastIndexOf('.')),  
        )  
    }  
    
    private fun getNestedDirectoryPaths(baseDirectoryPath: String): List<String> {  
        val nestedDirectoryPaths = mutableListOf<String>()  
        val queue: Queue<File> = ArrayDeque()  
        val baseDirectory = File(baseDirectoryPath)  
  
        if (baseDirectory.isDirectory) {  
            queue.add(baseDirectory)  
        }  
        while (queue.isNotEmpty()) {  
            val directory = queue.poll()  
            nestedDirectoryPaths.add(directory.absolutePath)  
  
            val files = directory.listFiles()  
            files?.forEach {
                if (it.isDirectory) {  
                    queue.add(it)  
                } 
            }  
        }  
  
        return nestedDirectoryPaths  
    }  
}