MiaoScript/src/main/java/pw/yumc/MiaoScript/api/loader/JarLoader.java

68 lines
2.3 KiB
Java

package pw.yumc.MiaoScript.api.loader;
import lombok.SneakyThrows;
import java.io.File;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.net.URL;
public class JarLoader {
private static sun.misc.Unsafe unsafe;
private static long offset;
private static Object parentUcp;
private static Object ucp;
private static MethodHandle addURLMethodHandle;
static {
initReflect();
}
@SneakyThrows
public static File load(File file) {
addURLMethodHandle.invoke(ucp, file.toURI().toURL());
return file;
}
@SneakyThrows
public static File parentLoad(File file) {
if (parentUcp == null)
throw new IllegalStateException("parentUcp is null.");
addURLMethodHandle.invoke(parentUcp, file.toURI().toURL());
return file;
}
@SneakyThrows
public static File load(File file, ClassLoader loader) {
addURLMethodHandle.invoke(unsafe.getObject(loader, offset), file.toURI().toURL());
return file;
}
private static void initReflect() {
try {
ClassLoader loader = JarLoader.class.getClassLoader();
Field theUnsafe = sun.misc.Unsafe.class.getDeclaredField("theUnsafe");
theUnsafe.setAccessible(true);
unsafe = (sun.misc.Unsafe) theUnsafe.get(null);
Field field = MethodHandles.Lookup.class.getDeclaredField("IMPL_LOOKUP");
MethodHandles.Lookup lookup = (MethodHandles.Lookup) unsafe.getObject(unsafe.staticFieldBase(field), unsafe.staticFieldOffset(field));
Field ucpField;
try {
ucpField = loader.getClass().getDeclaredField("ucp");
} catch (NoSuchFieldException e) {
ucpField = loader.getClass().getSuperclass().getDeclaredField("ucp");
}
offset = unsafe.objectFieldOffset(ucpField);
ucp = unsafe.getObject(loader, offset);
Method method = ucp.getClass().getDeclaredMethod("addURL", URL.class);
addURLMethodHandle = lookup.unreflect(method);
if (loader.getParent() != null)
parentUcp = unsafe.getObject(loader.getParent(), offset);
} catch (Throwable e) {
throw new RuntimeException(e);
}
}
}