NoClassDefError when using classes from a .jar – Twitter API

I am attempting to use classes from a .jar file in a my .java file Tweetauthent. The .jar file is in another directory. I make a request to the Twitter rest api to obtain a bearertoken. Tweetauthent compiles when I run

     -javac -cp /path/to/jar Tweetauthent.java

This is the code

import java.io.BufferedReader;
import java.lang.StringBuilder;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.URLEncoder;

public class Tweetauthent{
 static String consumerkey = "astring";
 static String consumersecret = "astring";
 static String endurl = "https://api.twitter.com/oauth2/token";

public static void main(String []args){

    Tweetauthent t = new Tweetauthent();
    try{
        System.out.println(t.requestBearerToken(endurl));
    }catch(IOException e){
        System.out.println(e);
    }   
}
public static String encodeKeys(String consumerKey,String consumerSecret){
    try{
        String encodedConsumerKey = URLEncoder.encode(consumerKey,"UTF-8");
        String encodedConsumerSecret = URLEncoder.encode(consumerSecret,"UTF-8");

        String fullKey = encodedConsumerKey + ":" + encodedConsumerSecret;
        byte[] encodedBytes = Base64.getEncoder().encode(fullKey.getBytes());
        return new String(encodedBytes);
    }catch(UnsupportedEncodingException e){
        return new String();
    }

}
public static String requestBearerToken(String endPointURL) throws IOException {
    HttpsURLConnection connection = null;
    String encodedCredentials = encodeKeys("<consumerkey>","<consumersecret>");
    try{
        URL url = new URL(endPointURL);
        connection = (HttpsURLConnection)url.openConnection();
        connection.setDoOutput(true);
        connection.setDoInput(true);
        connection.setRequestProperty("Host","api.twitter.com");
        connection.setRequestProperty("User-Agent","TweetPersonalityAnalyzer");
        connection.setRequestProperty("Authorization","Basic " + encodedCredentials);
        connection.setRequestProperty("Content-Type","application/x-www-form-urlencoded;charset=UTF-8");
        connection.setRequestProperty("Content-Length","29");

        writeRequest(connection, "grant_type=client_credentials");

        JSONObject obj = (JSONObject)JSONValue.parse(readResponse(connection));

        if(obj != null){
            String tokenType = (String)obj.get("token_type");
            String token = (String)obj.get("access_token");

            return ((tokenType.equals("bearer")) && (token != null)) ? token : ""; 
        }
        return new String();

    }catch(MalformedURLException e){
        throw new IOException("Invalid endpoint URL specified.", e);
    }
    finally{
        if( connection != null){
            connection.disconnect();
        }
    }

}
public static boolean writeRequest(HttpsURLConnection connection, String textBody){
    try{
        BufferedWriter wr = new BufferedWriter(new OutputStreamWriter(connection.getOutputStream()));
        wr.write(textBody);
        wr.flush();
        wr.close();

        return true;
    }
    catch(IOException e){
        return false;
    }
}
public static String readResponse(HttpsURLConnection connection){
    try {
        StringBuilder str = new StringBuilder();

        BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
        String line = "";
        while((line = br.readLine()) != null){
            str.append(line + System.getProperty("line.separator"));
        }
    return str.toString();
}catch(IOException e){
    return new String();
}

}

The error I get when I run

   java Tweetauthent

is

    java.lang.NoClassDefFoundError: org/json/simple/JSONValue
          at Tweetauthent.requestBearerToken(Tweetauthent.java:61)
          at Tweetauthent.main(Tweetauthent.java:27)
    Caused by: java.lang.ClassNotFoundException: 
    org.json.simple.JSONValue
         at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
         at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
      at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335)
      at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
     ... 2 more

From what I understand the NoClassDefFoundError is thrown when the JVM cant find neccesary class files that the .java file used to compile. What would be causing this? Is there a way to add the path of the jar too -java? Oh and with expected consumerkey and secret strings.

UPDATE: when I add the classpath to java

    java /path/to/jar Tweethauthent

I get Error: could not find or load main class Tweetauthent

Any help would be greatly appreciated thank you!