PlaceholderAPI/src/main/java/me/clip/placeholderapi/util/FileUtil.java

74 lines
2.4 KiB
Java

package me.clip.placeholderapi.util;
import java.io.File;
import java.io.FilenameFilter;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarInputStream;
import me.clip.placeholderapi.PlaceholderAPIPlugin;
public class FileUtil {
public static List<Class<?>> getClasses(String folder, Class<?> type) {
List<Class<?>> list = new ArrayList<>();
try {
File f = new File(PlaceholderAPIPlugin.getInstance().getDataFolder(), folder);
if (!f.exists()) {
if (!f.mkdir()) {
PlaceholderAPIPlugin.getInstance().getLogger().severe("Failed to create " + folder + " folder!");
}
return list;
}
FilenameFilter fileNameFilter = (dir, name) -> {
int i = name.lastIndexOf('.');
return i > 0 && name.substring(i).equals(".jar");
};
File[] jars = f.listFiles(fileNameFilter);
if (jars == null) {
return list;
}
for (File file : jars) {
list = gather(file.toURI().toURL(), list, type);
}
return list;
} catch (Throwable t) {}
return null;
}
private static List<Class<?>> gather(URL jar, List<Class<?>> list, Class<?> clazz) {
if (list == null) {
list = new ArrayList<>();
}
try {
URLClassLoader cl = new URLClassLoader(new URL[]{jar}, clazz.getClassLoader());
JarInputStream jis = new JarInputStream(jar.openStream());
while (true) {
JarEntry j = jis.getNextJarEntry();
if (j == null) {
break;
}
String name = j.getName();
if (name == null || name.isEmpty()) {
continue;
}
if (name.endsWith(".class")) {
name = name.replace("/", ".");
String cname = name.substring(0, name.lastIndexOf(".class"));
Class<?> c = cl.loadClass(cname);
if (clazz.isAssignableFrom(c)) {
list.add(c);
}
}
}
cl.close();
jis.close();
} catch (Throwable t) {
}
return list;
}
}