org.springframework.data.rest.webmvc.config.ArgumentResolverPagingAndSortingTemplateVariables.java Source code

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Here is the source code for org.springframework.data.rest.webmvc.config.ArgumentResolverPagingAndSortingTemplateVariables.java

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/*
 * Copyright 2015-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.data.rest.webmvc.config;

import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

import org.springframework.core.MethodParameter;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.data.rest.webmvc.support.PagingAndSortingTemplateVariables;
import org.springframework.data.web.HateoasPageableHandlerMethodArgumentResolver;
import org.springframework.data.web.HateoasSortHandlerMethodArgumentResolver;
import org.springframework.hateoas.TemplateVariables;
import org.springframework.util.Assert;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.util.UriComponents;
import org.springframework.web.util.UriComponentsBuilder;

/**
 * {@link PagingAndSortingTemplateVariables} implementation to delegate to the HATEOAS-enabled
 * {@link HandlerMethodArgumentResolver}s for {@link Pageable} and {@link Sort}.
 *
 * @author Oliver Gierke
 * @since 2.3
 */
class ArgumentResolverPagingAndSortingTemplateVariables implements PagingAndSortingTemplateVariables {

    private static final Set<Class<?>> SUPPORTED_TYPES = Collections
            .unmodifiableSet(new HashSet<Class<?>>(Arrays.<Class<?>>asList(Pageable.class, Sort.class)));

    private final HateoasPageableHandlerMethodArgumentResolver pagingResolver;
    private final HateoasSortHandlerMethodArgumentResolver sortResolver;

    /**
     * Creates a new {@link ArgumentResolverPagingAndSortingTemplateVariables} using the given
     * {@link HateoasPageableHandlerMethodArgumentResolver} and {@link HateoasSortHandlerMethodArgumentResolver}.
     *
     * @param pagingResolver must not be {@literal null}.
     * @param sortResolver must not be {@literal null}.
     */
    public ArgumentResolverPagingAndSortingTemplateVariables(
            HateoasPageableHandlerMethodArgumentResolver pagingResolver,
            HateoasSortHandlerMethodArgumentResolver sortResolver) {

        Assert.notNull(pagingResolver, "HateoasPageableHandlerMethodArgumentResolver must not be null!");
        Assert.notNull(sortResolver, "HateoasSortHandlerMethodArgumentResolver must not be null!");

        this.pagingResolver = pagingResolver;
        this.sortResolver = sortResolver;
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.data.rest.webmvc.support.PagingAndSortingTemplateVariables#getPaginationTemplateVariables(org.springframework.core.MethodParameter, org.springframework.web.util.UriComponents)
     */
    @Override
    public TemplateVariables getPaginationTemplateVariables(MethodParameter parameter, UriComponents components) {
        return pagingResolver.getPaginationTemplateVariables(parameter, components);
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.data.rest.webmvc.support.PagingAndSortingTemplateVariables#getSortTemplateVariables(org.springframework.core.MethodParameter, org.springframework.web.util.UriComponents)
     */
    @Override
    public TemplateVariables getSortTemplateVariables(MethodParameter parameter, UriComponents template) {
        return sortResolver.getSortTemplateVariables(parameter, template);
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.hateoas.server.mvc.UriComponentsContributor#enhance(org.springframework.web.util.UriComponentsBuilder, org.springframework.core.MethodParameter, java.lang.Object)
     */
    @Override
    public void enhance(UriComponentsBuilder builder, MethodParameter parameter, Object value) {

        if (value instanceof Pageable) {
            pagingResolver.enhance(builder, parameter, value);
        } else if (value instanceof Sort) {
            sortResolver.enhance(builder, parameter, value);
        }
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.hateoas.server.mvc.UriComponentsContributor#supportsParameter(org.springframework.core.MethodParameter)
     */
    @Override
    public boolean supportsParameter(MethodParameter parameter) {
        return SUPPORTED_TYPES.contains(parameter.getParameterType());
    }
}