<dependencies>
 <!-- core library -->
 <dependency>
	<groupId>org.jboss.resteasy</groupId>
	 <artifactId>resteasy-jaxrs</artifactId>
	<version>3.0.2.Final</version>
 </dependency>
<!-- JAXB support -->
<dependency>
  <groupId>org.jboss.resteasy</groupId>
	<artifactId>resteasy-jaxb-provider</artifactId>
  <version>3.0.2.Final</version>
</dependency>
<dependency>
	<groupId>org.jboss.resteasy</groupId>
	<artifactId>jaxrs-api</artifactId>
	<version>3.0.2.Final</version>
</dependency>
<dependency>
	<groupId>net.sf.scannotation</groupId>
	<artifactId>scannotation</artifactId>
	<version>1.0.3</version>
</dependency>
</dependencies>

@Provider
public class SecurityInterceptor implements javax.ws.rs.container.ContainerRequestFilter
{
    @Override
	public void filter(ContainerRequestContext requestContext)
	{
		//More code...
	}
}

	ResourceMethodInvoker methodInvoker = (ResourceMethodInvoker) 
				requestContext.getProperty("org.jboss.resteasy.core.ResourceMethodInvoker");
	Method method = methodInvoker.getMethod();

package com.howtodoinjava.demo.rest.security;

import java.io.IOException;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.StringTokenizer;

import javax.annotation.security.DenyAll;
import javax.annotation.security.PermitAll;
import javax.annotation.security.RolesAllowed;
import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.ext.Provider;

import org.jboss.resteasy.core.Headers;
import org.jboss.resteasy.core.ResourceMethodInvoker;
import org.jboss.resteasy.core.ServerResponse;
import org.jboss.resteasy.util.Base64;

/**
 * This interceptor verify the access permissions for a user 
 * based on username and passowrd provided in request
 * */
@Provider
public class SecurityInterceptor implements javax.ws.rs.container.ContainerRequestFilter
{
	private static final String AUTHORIZATION_PROPERTY = "Authorization";
	private static final String AUTHENTICATION_SCHEME = "Basic";
	private static final ServerResponse ACCESS_DENIED = new ServerResponse("Access denied for this resource", 401, new Headers<Object>());;
	private static final ServerResponse ACCESS_FORBIDDEN = new ServerResponse("Nobody can access this resource", 403, new Headers<Object>());;
	private static final ServerResponse SERVER_ERROR = new ServerResponse("INTERNAL SERVER ERROR", 500, new Headers<Object>());;

	@Override
	public void filter(ContainerRequestContext requestContext)
	{
		ResourceMethodInvoker methodInvoker = (ResourceMethodInvoker) requestContext.getProperty("org.jboss.resteasy.core.ResourceMethodInvoker");
		Method method = methodInvoker.getMethod();
		//Access allowed for all 
		if( ! method.isAnnotationPresent(PermitAll.class))
		{
			//Access denied for all 
			if(method.isAnnotationPresent(DenyAll.class))
			{
				requestContext.abortWith(ACCESS_FORBIDDEN);
				return;
			}

			//Get request headers
			final MultivaluedMap<String, String> headers = requestContext.getHeaders();

			//Fetch authorization header
		    final List<String> authorization = headers.get(AUTHORIZATION_PROPERTY);

		    //If no authorization information present; block access
		    if(authorization == null || authorization.isEmpty())
		    {
		    	requestContext.abortWith(ACCESS_DENIED);
		    	return;
		    }

		    //Get encoded username and password
		    final String encodedUserPassword = authorization.get(0).replaceFirst(AUTHENTICATION_SCHEME + " ", "");

		    //Decode username and password
		    String usernameAndPassword = null;
			try {
				usernameAndPassword = new String(Base64.decode(encodedUserPassword));
			} catch (IOException e) {
				requestContext.abortWith(SERVER_ERROR);
				return;
			}

			//Split username and password tokens
		    final StringTokenizer tokenizer = new StringTokenizer(usernameAndPassword, ":");
		    final String username = tokenizer.nextToken();
		    final String password = tokenizer.nextToken();

		    //Verifying Username and password
		    System.out.println(username);
		    System.out.println(password);

		    //Verify user access
			if(method.isAnnotationPresent(RolesAllowed.class))
			{
				RolesAllowed rolesAnnotation = method.getAnnotation(RolesAllowed.class);
				Set<String> rolesSet = new HashSet<String>(Arrays.asList(rolesAnnotation.value()));

				//Is user valid?
				if( ! isUserAllowed(username, password, rolesSet))
				{
					requestContext.abortWith(ACCESS_DENIED);
					return;
				}
			}
		}
	}
	private boolean isUserAllowed(final String username, final String password,	final Set<String> rolesSet) 
	{
		boolean isAllowed = false;

		//Step 1\. Fetch password from database and match with password in argument
		//If both match then get the defined role for user from database and continue; else return isAllowed [false]
		//Access the database and do this part yourself
		//String userRole = userMgr.getUserRole(username);
		String userRole = "ADMIN";

		//Step 2\. Verify user role
		if(rolesSet.contains(userRole))
		{
			isAllowed = true;
		}
		return isAllowed;
	}

}