com.miserablemind.butter.resolvers.user.ActiveUserMethodArgumentResolver.java Source code

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Here is the source code for com.miserablemind.butter.resolvers.user.ActiveUserMethodArgumentResolver.java

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package com.miserablemind.butter.resolvers.user;

import com.miserablemind.butter.domain.model.user.user.AppUser;
import org.springframework.core.MethodParameter;
import org.springframework.security.core.Authentication;
import org.springframework.web.bind.support.WebArgumentResolver;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;

import java.security.Principal;

/*
 * Miserable Mind
 * http://www.butter.miserablemind.com
 * The MIT License (MIT)
 */

/**
 * Method Argument Resolver for @{@link ActiveUser}. It allows to wire authenticated user to controller methods via
 * {code @ActiveUser} annotated method argument.
 *
 * @author <a href="http://www.miserablemind.com" target="_blank">miserablemind</a>
 */
public class ActiveUserMethodArgumentResolver implements HandlerMethodArgumentResolver {

    /**
     * Checks if parameter is of the right type and has correct annotation (@ActiveUser in this case)
     *
     * @param methodParameter parameter being resolved.
     * @return {@code true} if parameter is supported.
     */
    @Override
    public boolean supportsParameter(MethodParameter methodParameter) {
        return methodParameter.getParameterAnnotation(ActiveUser.class) != null
                && methodParameter.getParameterType().equals(AppUser.class);
    }

    /**
     * Resolves the method parameter. Overrides {@link HandlerMethodArgumentResolver} method resolveArgument.
     *
     * @param methodParameter parameter being resolved. Value is used for passing to supportsParameter method.
     * @param mavContainer    model and view container. In this instance it is not used for anything.
     * @param webRequest      web request used for getting the principal.
     * @param binderFactory   WebDataBinderFactory. In this case it is not used for anything.
     * @return {@link AppUser} app user if there is an authenticated user. {@code null} if there is no authenticated user,
     * {@code WebArgumentResolver.UNRESOLVED} if method parameter is not supported.
     * @throws Exception
     */
    @Override
    public Object resolveArgument(MethodParameter methodParameter, ModelAndViewContainer mavContainer,
            NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {

        if (this.supportsParameter(methodParameter)) {
            Principal principal = webRequest.getUserPrincipal();
            if (null != principal) {
                return ((Authentication) principal).getPrincipal();
            } else {
                return null;
            }
        }
        return WebArgumentResolver.UNRESOLVED;

    }

}