java 如何列出jar包中jar包里的所有文件和目录？

Question

如这样一个目录/Users/xxx/IdeaProjects/abc/web/target/web.jar!/BOOT-INF/lib/rest-0.0.1.jar!/com/tg/tiny
/Users/xxx/IdeaProjects/abc/web/target/web.jar这个jar包下的文件目录可以这样得到

JarFile localJarFile = new JarFile(new File("/Users/xxx/IdeaProjects/abc/web/target/web.jar"));
Enumeration<JarEntry> entries = localJarFile.entries();
        while (entries.hasMoreElements()) {
            JarEntry jarEntry = entries.nextElement();
            System.out.println(jarEntry.getName());
        }

那么这个web.jar里的rest-0.0.1.jar下的文件目录如何得到？

Answer 1

        URL url = new URL("jar", null, 0, "file:/Users/xxx/IdeaProjects/web/target/web.jar!/BOOT-INF/lib/rest.jar");
        URLConnection con = url.openConnection();
        if (con instanceof JarURLConnection) {
            JarURLConnection result = (JarURLConnection) con;
            JarInputStream jarInputStream = new JarInputStream(result.getInputStream());
            JarEntry entry;
            while ((entry = jarInputStream.getNextJarEntry()) != null) {
                System.out.println(entry.getName());
            }
        }