Java tutorial
/* * Copyright 2012-2014 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 * * http://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.lightadmin.core.web; import com.google.common.base.Predicate; import org.lightadmin.api.config.utils.ScopeMetadataUtils; import org.lightadmin.core.config.domain.DomainTypeAdministrationConfiguration; import org.lightadmin.core.config.domain.GlobalAdministrationConfiguration; import org.lightadmin.core.config.domain.scope.ScopeMetadata; import org.lightadmin.core.persistence.repository.invoker.DynamicRepositoryInvoker; import org.lightadmin.core.persistence.support.SpecificationCreator; import org.springframework.beans.factory.BeanFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.core.convert.ConversionService; import org.springframework.data.domain.Page; import org.springframework.data.domain.PageImpl; import org.springframework.data.domain.Pageable; import org.springframework.data.domain.Sort; import org.springframework.data.jpa.domain.Specification; import org.springframework.data.mapping.PersistentEntity; import org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler; import org.springframework.data.rest.webmvc.RepositoryRestController; import org.springframework.data.rest.webmvc.RootResourceInformation; import org.springframework.data.web.PagedResourcesAssembler; import org.springframework.hateoas.Resource; import org.springframework.hateoas.Resources; import org.springframework.http.HttpStatus; import org.springframework.http.ResponseEntity; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.context.request.WebRequest; import java.util.List; import static com.google.common.collect.Collections2.filter; import static com.google.common.collect.Lists.newArrayList; import static java.util.Collections.singletonList; import static org.lightadmin.api.config.utils.ScopeMetadataUtils.*; import static org.springframework.data.jpa.domain.Specifications.where; import static org.springframework.data.rest.webmvc.ControllerUtils.EMPTY_RESOURCE_LIST; import static org.springframework.web.bind.annotation.RequestMethod.GET; @SuppressWarnings("unchecked") @RepositoryRestController public class RepositoryScopedSearchController { private static final String BASE_MAPPING = "/{repository}/scope/{scopeName}"; private final ConversionService conversionService; private final BeanFactory beanFactory; private final PagedResourcesAssembler pagedResourcesAssembler; @Autowired public RepositoryScopedSearchController( @Qualifier("defaultConversionService") ConversionService conversionService, PagedResourcesAssembler<Object> pagedResourcesAssembler, BeanFactory beanFactory) { this.pagedResourcesAssembler = pagedResourcesAssembler; this.conversionService = conversionService; this.beanFactory = beanFactory; } @RequestMapping(value = BASE_MAPPING + "/search/count", method = GET) public ResponseEntity<?> countItems(DomainTypeAdministrationConfiguration domainTypeAdministrationConfiguration, RootResourceInformation repoRequest, WebRequest request, @PathVariable String scopeName) { DynamicRepositoryInvoker repositoryInvoker = (DynamicRepositoryInvoker) repoRequest.getInvoker(); PersistentEntity<?, ?> persistentEntity = repoRequest.getPersistentEntity(); final ScopeMetadata scope = domainTypeAdministrationConfiguration.getScopes().getScope(scopeName); final Specification filterSpecification = specificationFromRequest(request, persistentEntity); if (isPredicateScope(scope)) { final PredicateScopeMetadata predicateScope = (PredicateScopeMetadata) scope; return new ResponseEntity(countItemsBySpecificationAndPredicate(repositoryInvoker, filterSpecification, predicateScope.predicate()), HttpStatus.OK); } if (isSpecificationScope(scope)) { final Specification scopeSpecification = ((ScopeMetadataUtils.SpecificationScopeMetadata) scope) .specification(); return new ResponseEntity( countItemsBySpecification(repositoryInvoker, and(scopeSpecification, filterSpecification)), HttpStatus.OK); } return new ResponseEntity(countItemsBySpecification(repositoryInvoker, filterSpecification), HttpStatus.OK); } @RequestMapping(value = BASE_MAPPING + "/search", method = GET) public ResponseEntity<?> filterEntities( DomainTypeAdministrationConfiguration domainTypeAdministrationConfiguration, RootResourceInformation repoRequest, PersistentEntityResourceAssembler assembler, WebRequest request, Pageable pageable, @PathVariable String scopeName) throws Exception { DynamicRepositoryInvoker repositoryInvoker = (DynamicRepositoryInvoker) repoRequest.getInvoker(); PersistentEntity<?, ?> persistentEntity = repoRequest.getPersistentEntity(); final ScopeMetadata scope = domainTypeAdministrationConfiguration.getScopes().getScope(scopeName); final Specification filterSpecification = specificationFromRequest(request, persistentEntity); if (isPredicateScope(scope)) { final PredicateScopeMetadata predicateScope = (PredicateScopeMetadata) scope; final Page page = findBySpecificationAndPredicate(repositoryInvoker, filterSpecification, predicateScope.predicate(), pageable); Object resources = resultToResources(page, assembler); return new ResponseEntity(resources, HttpStatus.OK); } if (isSpecificationScope(scope)) { final Specification scopeSpecification = ((ScopeMetadataUtils.SpecificationScopeMetadata) scope) .specification(); Page page = findItemsBySpecification(repositoryInvoker, and(scopeSpecification, filterSpecification), pageable); Object resources = resultToResources(page, assembler); return new ResponseEntity(resources, HttpStatus.OK); } Page page = findItemsBySpecification(repositoryInvoker, filterSpecification, pageable); Object resources = resultToResources(page, assembler); return new ResponseEntity(resources, HttpStatus.OK); } protected Resources resultToResources(Object result, PersistentEntityResourceAssembler assembler) { if (result instanceof Page) { Page<Object> page = (Page<Object>) result; return entitiesToResources(page, assembler); } if (result instanceof Iterable) { return entitiesToResources((Iterable<Object>) result, assembler); } if (null == result) { return new Resources(EMPTY_RESOURCE_LIST); } Resource<Object> resource = assembler.toResource(result); return new Resources(singletonList(resource)); } protected Resources<? extends Resource<Object>> entitiesToResources(Page<Object> page, PersistentEntityResourceAssembler assembler) { return pagedResourcesAssembler.toResource(page, assembler); } protected Resources<Resource<Object>> entitiesToResources(Iterable<Object> entities, PersistentEntityResourceAssembler assembler) { List<Resource<Object>> resources = newArrayList(); for (Object obj : entities) { resources.add(obj == null ? null : assembler.toResource(obj)); } return new Resources(resources); } private Specification specificationFromRequest(WebRequest request, PersistentEntity<?, ?> persistentEntity) { return specificationCreator().toSpecification(persistentEntity, request.getParameterMap()); } private long countItemsBySpecificationAndPredicate(DynamicRepositoryInvoker repository, final Specification specification, Predicate predicate) { final List<?> items = findItemsBySpecification(repository, specification); return filter(items, predicate).size(); } private long countItemsBySpecification(final DynamicRepositoryInvoker invoker, final Specification specification) { return invoker.count(specification); } private List<?> findItemsBySpecification(final DynamicRepositoryInvoker invoker, final Specification specification) { return invoker.findAll(specification); } private Specification and(Specification specification, Specification otherSpecification) { return where(specification).and(otherSpecification); } private Page<?> findItemsBySpecification(final DynamicRepositoryInvoker invoker, final Specification specification, final Pageable pageSort) { return invoker.findAll(specification, pageSort); } private List<?> findItemsBySpecification(final DynamicRepositoryInvoker invoker, final Specification specification, final Sort sort) { return invoker.findAll(specification, sort); } private Page<?> selectPage(List<Object> items, Pageable pageable) { final List<Object> itemsOnPage = items.subList(pageable.getOffset(), Math.min(items.size(), pageable.getOffset() + pageable.getPageSize())); return new PageImpl(itemsOnPage, pageable, items.size()); } private Page findBySpecificationAndPredicate(DynamicRepositoryInvoker invoker, final Specification specification, Predicate predicate, final Pageable pageable) { final List<?> items = findItemsBySpecification(invoker, specification, pageable.getSort()); return selectPage(newArrayList(filter(items, predicate)), pageable); } private GlobalAdministrationConfiguration globalAdministrationConfiguration() { return beanFactory.getBean(GlobalAdministrationConfiguration.class); } private SpecificationCreator specificationCreator() { return new SpecificationCreator(this.conversionService, globalAdministrationConfiguration()); } }