使用Java访问类路径中特定文件夹中的文件

我想在com.example.resources包中读取一堆文本文件。 我可以使用以下代码读取单个文件：

InputStream is = MyObject.class.getResourceAsStream("resources/file1.txt") InputStreamReader sReader = new InputStreamReader(is); BefferedReader bReader = new BufferedReader(sReader); ... 

有没有办法获取文件列表，然后将每个元素传递给getResourceAsStream ？

编辑：在ramsinb建议我改变我的代码如下：

 BufferedReader br = new BufferedReader(new InputStreamReader(MyObject.class.getResourceAsStream("resources"))); String fileName; while((fileName = br.readLine()) != null){ // access fileName } 

Answer 1

如果将目录传递给getResourceAsStream方法，则它将返回目录中的文件列表（或至少是其中的一个流）。

 Thread.currentThread().getContextClassLoader().getResourceAsStream(...) 

我故意使用Thread获取资源，因为它将确保我获得父类加载器。 这在Java EE环境中很重要，但对您的情况可能不是太多。

Answer 2

这个SO线程详细讨论了这种技术。 下面是一个有用的Java方法，它列出给定资源文件夹中的文件。

 /** * List directory contents for a resource folder. Not recursive. * This is basically a brute-force implementation. * Works for regular files and also JARs. * * @author Greg Briggs * @param clazz Any java class that lives in the same place as the resources you want. * @param path Should end with "/", but not start with one. * @return Just the name of each member item, not the full paths. * @throws URISyntaxException * @throws IOException */ String[] getResourceListing(Class clazz, String path) throws URISyntaxException, IOException { URL dirURL = clazz.getClassLoader().getResource(path); if (dirURL != null && dirURL.getProtocol().equals("file")) { /* A file path: easy enough */ return new File(dirURL.toURI()).list(); } if (dirURL == null) { /* * In case of a jar file, we can't actually find a directory. * Have to assume the same jar as clazz. */ String me = clazz.getName().replace(".", "/")+".class"; dirURL = clazz.getClassLoader().getResource(me); } if (dirURL.getProtocol().equals("jar")) { /* A JAR path */ String jarPath = dirURL.getPath().substring(5, dirURL.getPath().indexOf("!")); //strip out only the JAR file JarFile jar = new JarFile(URLDecoder.decode(jarPath, "UTF-8")); Enumeration entries = jar.entries(); //gives ALL entries in jar Set result = new HashSet(); //avoid duplicates in case it is a subdirectory while(entries.hasMoreElements()) { String name = entries.nextElement().getName(); if (name.startsWith(path)) { //filter according to the path String entry = name.substring(path.length()); int checkSubdir = entry.indexOf("/"); if (checkSubdir >= 0) { // if it is a subdirectory, we just return the directory name entry = entry.substring(0, checkSubdir); } result.add(entry); } } return result.toArray(new String[result.size()]); } throw new UnsupportedOperationException("Cannot list files for URL "+dirURL); } 

Answer 3

我想那就是你想要的：

 String currentDir = new java.io.File(".").toURI().toString(); // AClass = A class in this package String pathToClass = AClass.class.getResource("/packagename).toString(); String packagePath = (pathToClass.substring(currentDir.length() - 2)); String file; File folder = new File(packagePath); File[] filesList= folder.listFiles(); for (int i = 0; i < filesList.length; i++) { if (filesList[i].isFile()) { file = filesList[i].getName(); if (file.endsWith(".txt") || file.endsWith(".TXT")) { // DO YOUR THING WITH file } } }