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public class WalkClasspathAllClasses {
public static void main(String[] args) throws URISyntaxException, IOException {
List<URL> urls = new ArrayList<>();
//获取Classpath
if (WalkClasspathAllClasses.class.getClassLoader() instanceof URLClassLoader) {
Collections.addAll(urls, ((URLClassLoader) WalkClasspathAllClasses.class.getClassLoader()).getURLs());
} else {
for (String s : System.getProperty("java.class.path").split(";")) {
urls.add(new File(s).toURI().toURL());
}
}
//遍历所有类
walkAllClasses(urls).forEach(System.out::println);
}
private static Set<String> walkAllClasses(List<URL> urls) throws URISyntaxException, IOException {
Set<String> classes = new HashSet<>();
for (URL url : urls) {
if (url.toURI().getScheme().equals("file")) {
//判断Scheme是不是file
File file = new File(url.toURI());
if (!file.exists()) continue;//是存在
if (file.isDirectory()) {
//如果是目录
Files.walkFileTree(file.toPath(), new SimpleFileVisitor<Path>() {
//遍历所有文件
@Override
public FileVisitResult visitFile(Path path, BasicFileAttributes attrs) throws IOException {
if (path.toFile().getName().endsWith(".class")) {
//判断是否为class后缀
//去除路径截取包名
String substring = path.toFile().getAbsolutePath().substring(file.getAbsolutePath().length());
if (substring.startsWith(File.separator)) {
substring = substring.substring(1);
}
substring = substring.substring(0, substring.length() - 6);//去掉后缀
classes.add(substring.replace(File.separator, "."));//把路径替换为.
}
return super.visitFile(path, attrs);
}
});
} else if (file.getName().endsWith(".jar")) {
//如果是jar包
JarFile jarFile = new JarFile(file);
Enumeration<JarEntry> entries = jarFile.entries();
while (entries.hasMoreElements()) {
//遍历所有文件
JarEntry jarEntry = entries.nextElement();
if (!jarEntry.getName().endsWith(".class")) continue;//判断后缀是否为class
String replace = jarEntry.getName().replace("/", ".");//把路径替换为.
classes.add(replace.substring(0, replace.length() - 6));//去掉后缀
}
}
}
}
return classes;
}
}
