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Why am I getting the error "NoClassDefFoundError: sun/misc/Unsafe" when trying to load sounds using the LWJGL library?

This is the screenshot of my Eclipse project files.
I get the error below when I try to initiated a new Sound("Res/MouseClick.ogg") object in my class AudioPlayer at line 15.
package com.game;
import java.util.HashMap;
import java.util.Map;
import org.newdawn.slick.Music;
import org.newdawn.slick.Sound;
public class AudioPlayer {
public static Map<String, Sound> soundMap = new HashMap<String, Sound>();
public static Map<String, Music> musicMap = new HashMap<String, Music>();
public static void load() {
try {
soundMap.put("menu_sound", new Sound("Res/MouseClick.ogg")); // <- throws error
musicMap.put("music", new Music("Res/Background.ogg"));
} catch (Exception e) {
e.printStackTrace();
}
}
public static Music getMusic(String key) {
return musicMap.get(key);
}
public static Sound getSound(String key) {
return soundMap.get(key);
}
}
Exception in thread "main" java.lang.NoClassDefFoundError: sun/misc/Unsafe
at lwjgl/org.lwjgl.MemoryUtilSun$AccessorUnsafe.getUnsafeInstance(MemoryUtilSun.java:74)
at lwjgl/org.lwjgl.MemoryUtilSun$AccessorUnsafe.<init>(MemoryUtilSun.java:62)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
at java.base/java.lang.reflect.ReflectAccess.newInstance(ReflectAccess.java:166)
at java.base/jdk.internal.reflect.ReflectionFactory.newInstance(ReflectionFactory.java:404)
at java.base/java.lang.Class.newInstance(Class.java:590)
at lwjgl/org.lwjgl.MemoryUtil.loadAccessor(MemoryUtil.java:324)
at lwjgl/org.lwjgl.MemoryUtil.<clinit>(MemoryUtil.java:66)
at lwjgl/org.lwjgl.openal.ALC10.alcOpenDevice(ALC10.java:202)
at lwjgl/org.lwjgl.openal.AL.init(AL.java:160)
at lwjgl/org.lwjgl.openal.AL.create(AL.java:138)
at lwjgl/org.lwjgl.openal.AL.create(AL.java:102)
at lwjgl/org.lwjgl.openal.AL.create(AL.java:201)
at slick/org.newdawn.slick.openal.SoundStore$1.run(SoundStore.java:295)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:310)
at slick/org.newdawn.slick.openal.SoundStore.init(SoundStore.java:292)
at slick/org.newdawn.slick.Sound.<init>(Sound.java:54)
at Wave/com.game.AudioPlayer.load(AudioPlayer.java:15)
at Wave/com.game.Game.<init>(Game.java:37)
at Wave/com.game.Game.main(Game.java:157)
Caused by: java.lang.ClassNotFoundException: sun.misc.Unsafe
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
... 23 more

From your posted IDE screenshot I can see that you are using
Java 12, and
the Java Module System (module-info.java)
Note that sun/misc/Unsafe is a (legacy) Java internal API which for that reason and by default is encapsulated (hidden) away when using the Java Module System.
In order for your application (and your used library) to access it, you need to explicitly include it in your module-info.java by adding requires jdk.unsupported;
Alternatively, you may also not use the Java Module System – in which case it should simply work. However, I recommend to continue using the module system.

java.lang.ExceptionInInitializerError without a static initializer

I get a java.lang.ExceptionInInitializerError but I don´t have a static initializer.
Code:
public static final File STANDARD_INDEX_FILE = new File(HTMLFileLoader.class.getClassLoader().getResource("index.html").getPath()); // Line 16
The HTMLFileLoader class is empty.
Exception:
Exception in thread "main" java.lang.ExceptionInInitializerError
at net.guardian.Guardian.main(Guardian.java:12)
Caused by: java.lang.NullPointerException
at net.guardian.socket.MainSocket.<init>(MainSocket.java:16)
at net.guardian.socket.MainSocket.<clinit>(MainSocket.java:24)
... 1 more

This:
public static final File STANDARD_INDEX_FILE = new File(HTMLFileLoader.class.getClassLoader().getResource("index.html").getPath()); // Line 16
is exactly the same as this:
public static final File STANDARD_INDEX_FILE;
static {
STANDARD_INDEX_FILE = new File(HTMLFileLoader.class.getClassLoader().getResource("index.html").getPath()); // Line 16
}
As in, this is what it looks like in the compiled code.
As such, you do have a static initializer; and the exception is occuring somewhere in that initializer block.

When using Advice of byte buddy, Exception of java.lang.NoClassDefFoundError is throwed

For some reason, I've been analyzing my own old jar file(unfortunately source code's been lost).
I know what part I'm going to find but can't remember where it is.
So decide to use byte buddy to get all the run flow of jar file. It's enough to log parameter values and return values of all methods in all classes(except library class, e.g, java.lang.*).
I tried sample codes with a little modification, but straggle with just an exception:
public static void premain(final String agentArgs,
final Instrumentation inst) {
System.out.println(
"+++Hey, look: I'm instrumenting a freshly started JVM!");
new AgentBuilder.Default()
.type(ElementMatchers.any())
.transform(new MetricsTransformer())
.with(AgentBuilder.Listener.StreamWriting.toSystemOut())
.with(AgentBuilder.TypeStrategy.Default.REDEFINE)
.installOn(inst);
}
private static class MetricsTransformer implements AgentBuilder.Transformer {
#Override
public DynamicType.Builder<?> transform(
final DynamicType.Builder<?> builder,
final TypeDescription typeDescription,
final ClassLoader classLoader,
final JavaModule module) {
final AsmVisitorWrapper methodsVisitor =
Advice.to(EnterAdvice.class, ExitAdviceMethods.class)
.on(ElementMatchers.isAnnotatedWith(CollectMetrics.class)
.and(ElementMatchers.isMethod()));
final AsmVisitorWrapper constructorsVisitor =
Advice.to(EnterAdvice.class, ExitAdviceConstructors.class)
.on(ElementMatchers.isAnnotatedWith(CollectMetrics.class)
.and(ElementMatchers.isConstructor()));
return builder.visit(methodsVisitor).visit(constructorsVisitor);
}
private static class EnterAdvice {
#Advice.OnMethodEnter
static long enter() {
return System.nanoTime();
}
}
private static class ExitAdviceMethods {
#Advice.OnMethodExit(onThrowable = Throwable.class)
static void exit(#Advice.Origin final Executable executable,
#Advice.Enter final long startTime,
#Advice.Thrown final Throwable throwable) {
final long duration = System.nanoTime() - startTime;
System.out.println(duration);;
}
}
}
byte buddy's versions are 1.9.5, 1.7.11
jdk version: 1.8.0.191
and the Exception in the cmd:
E:\>cd E:\workshop\_android_studio\BounAgent\out\artifacts\BounAgent_jar
E:\BounAgent_jar>java -javaagent:BounAgent.jar -jar untitled.jar
Exception in thread "main" java.lang.NoClassDefFoundError: net/bytebuddy/matcher
/ElementMatcher
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.getDeclaredMethod(Unknown Source)
at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(Unknown Sou
rce)
at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(Unknown So
urce)
Caused by: java.lang.ClassNotFoundException: net.bytebuddy.matcher.ElementMatche
r
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 5 more
FATAL ERROR in native method: processing of -javaagent failed
Thanks in advance.

According to an article I found:
To launch your agent you must bundle the agent classes and resources in a jar, and in the jar manifest set the Agent-Class property to the name of your agent class containing the premain method. (An agent must always be bundled as a jar file, it cannot be specified in an exploded format.)
It appears that your agent JAR file ("BounAgent.jar") does not contain all of the dependencies in the correct form. Specifically, the bytebuddy classes are not in the JAR file. That is causing the agent classes to fail to load.

java.lang.NoClassDefFoundError: How to avoid loading of classes that do not exist? [duplicate]

This question already has answers here:
Does the JVM throw if an unused class is absent?
(3 answers)
How to avoid NoClassDefFoundError thrown by unused code in Java
(3 answers)
Closed 1 year ago.
We use some optional libraries. This libraries will only access if available. But the JIT produce already NoClassDefFoundError in the constructor of the class with optional access.
public Configuration {
public boolean libraryAvailable() {
return false; // some configuration that signal that the library is not available
}
}
public class Foo {
public Foo() {
... do some things
}
public void callLater() {
...
if( libraryAvailable() ) {
xyz();
}
...
}
private void xyz() {
new OptionalClass(); // available at compile time but not at runtime
}
}
How can I prevent that the JIT will load all possible dependencies of my call before calling the constructor?
java.lang.NoClassDefFoundError: com/inet/OptionalClass
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2671)
at java.lang.Class.getConstructor0(Class.java:3075)
at java.lang.Class.newInstance(Class.java:412)
...
Caused by: java.lang.ClassNotFoundException: com.inet.OptionalClass
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at com.inet.plugin.DependencyClassLoader.loadClass(DependencyClassLoader.java:104)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at com.inet.plugin.DependencyClassLoader.loadClass(DependencyClassLoader.java:138)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 9 more

Instead of importing your optional class, use Class.forName
try {
Class<?> act = Class.forName("com.bla.TestActivity");
MyInterface driver = act.newInstance();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}

You could write your own custom method as shown in below code to check if a class is available in classpath.
boolean result=false;
try {
Class.forName( "your.test.class" );
result=true;
} catch( ClassNotFoundException e ) {
//Class or Library is not available
}
return result;

The decoupling of class loading for unused code with a separate method only work if the constructor empty. If there is a constructor then you need to move the unused code in a separate class. This can also be an anonymous class.
For example:
new Object () { {
new OptionalClass();
} };

Exception in thread "main" java.lang.NoClassDefFoundError: MyJavaClasses/utility/MyCollection

I have a class named MyCollection in the directory
C:\Users\risha\OneDrive\RishavAgarwal\MyJavaClasses\utility\
inside the package - MyJavaClasses.utility
I have written a class named P22_Generics1 in the directory
C:\Users\risha\OneDrive\Documents\Java Practice\
This class uses the above created class.
I successfully compiled it using the command
javac P22_Generics1.java -cp C:\Users\risha\OneDrive\RishavAgarwal
Now, when I try to run it using the command java P22_Generics1, this error occurs
Exception in thread "main" java.lang.NoClassDefFoundError: MyJavaClasses/utility/MyCollection
at P22_Generics1.main(P22_Generics1.java:5)
Caused by: java.lang.ClassNotFoundException: Java.utils.Collection
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(Unknown Source)
at java.base/java.lang.ClassLoader.loadClass(Unknown Source)
... 1 more
What can I do to execute it successfully?
The P22_Generics1.java looks like this
import MyJavaClasses.utility.MyCollection;
public class P22_Generics1 {
public static void main(String[] args) {
MyCollection<Integer> collection = new MyCollection<>();
collection.add(1);
collection.add(4);
collection.add(10);
collection.add(5);
System.out.println(collection);
System.out.println(collection.get(3) + " " + collection.size());
}
}
The MyCollection.java starts like this
package MyJavaClasses.utility;
import java.util.*;
/**
* #author Rishav Agarwal
* #param <T> This describes the Type parameter
*/
public class MyCollection<T> implements Cloneable {
//...
}