DATACMNS-1211 - Add ReactiveSortHandlerMethodArgumentResolver.

Add ReactiveSortHandlerMethodArgumentResolver and extract shared code from imperative SortHandlerMethodArgumentResolver into SortHandlerMethodArgumentResolverSupport.

Original pull request: #264.

Author: mp911de

pom.xml

@@ -63,6 +63,11 @@
 			<artifactId>spring-web</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-webflux</artifactId>
+			<optional>true</optional>
+		</dependency>
 
 		<dependency>
 			<groupId>javax.servlet</groupId>

src/main/java/org/springframework/data/web/PageableHandlerMethodArgumentResolver.java

@@ -15,19 +15,11 @@
  */
 package org.springframework.data.web;
 
-import static org.springframework.data.web.SpringDataAnnotationUtils.*;
-
-import java.lang.reflect.Method;
-import java.util.Optional;
-
-import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.core.MethodParameter;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Sort;
 import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
-import org.springframework.util.StringUtils;
 import org.springframework.web.bind.support.WebDataBinderFactory;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.method.support.ModelAndViewContainer;
@@ -43,26 +35,11 @@
  * @author Mark Paluch
  * @author Christoph Strobl
  */
-public class PageableHandlerMethodArgumentResolver implements PageableArgumentResolver {
+public class PageableHandlerMethodArgumentResolver extends PageableHandlerMethodArgumentResolverSupport
+		implements PageableArgumentResolver {
 
 	private static final SortHandlerMethodArgumentResolver DEFAULT_SORT_RESOLVER = new SortHandlerMethodArgumentResolver();
-	private static final String INVALID_DEFAULT_PAGE_SIZE = "Invalid default page size configured for method %s! Must not be less than one!";
-
-	private static final String DEFAULT_PAGE_PARAMETER = "page";
-	private static final String DEFAULT_SIZE_PARAMETER = "size";
-	private static final String DEFAULT_PREFIX = "";
-	private static final String DEFAULT_QUALIFIER_DELIMITER = "_";
-	private static final int DEFAULT_MAX_PAGE_SIZE = 2000;
-	static final Pageable DEFAULT_PAGE_REQUEST = PageRequest.of(0, 20);
-
-	private Pageable fallbackPageable = DEFAULT_PAGE_REQUEST;
 	private SortArgumentResolver sortResolver;
-	private String pageParameterName = DEFAULT_PAGE_PARAMETER;
-	private String sizeParameterName = DEFAULT_SIZE_PARAMETER;
-	private String prefix = DEFAULT_PREFIX;
-	private String qualifierDelimiter = DEFAULT_QUALIFIER_DELIMITER;
-	private int maxPageSize = DEFAULT_MAX_PAGE_SIZE;
-	private boolean oneIndexedParameters = false;
 
 	/**
 	 * Constructs an instance of this resolved with a default {@link SortHandlerMethodArgumentResolver}.
@@ -239,106 +216,17 @@ public boolean supportsParameter(MethodParameter parameter) {
 	public Pageable resolveArgument(MethodParameter methodParameter, @Nullable ModelAndViewContainer mavContainer,
 			NativeWebRequest webRequest, @Nullable WebDataBinderFactory binderFactory) {
 
-		assertPageableUniqueness(methodParameter);
-
-		Optional<Pageable> defaultOrFallback = getDefaultFromAnnotationOrFallback(methodParameter).toOptional();
-
-		String pageString = webRequest.getParameter(getParameterNameToUse(pageParameterName, methodParameter));
-		String pageSizeString = webRequest.getParameter(getParameterNameToUse(sizeParameterName, methodParameter));
+		String page = webRequest.getParameter(getParameterNameToUse(getPageParameterName(), methodParameter));
+		String pageSize = webRequest.getParameter(getParameterNameToUse(getSizeParameterName(), methodParameter));
 
-		Optional<Integer> page = parseAndApplyBoundaries(pageString, Integer.MAX_VALUE, true);
-		Optional<Integer> pageSize = parseAndApplyBoundaries(pageSizeString, maxPageSize, false);
-
-		if (!(page.isPresent() && pageSize.isPresent()) && !defaultOrFallback.isPresent()) {
-			return Pageable.unpaged();
-		}
-
-		int p = page
-				.orElseGet(() -> defaultOrFallback.map(Pageable::getPageNumber).orElseThrow(IllegalStateException::new));
-		int ps = pageSize
-				.orElseGet(() -> defaultOrFallback.map(Pageable::getPageSize).orElseThrow(IllegalStateException::new));
-
-		// Limit lower bound
-		ps = ps < 1 ? defaultOrFallback.map(Pageable::getPageSize).orElseThrow(IllegalStateException::new) : ps;
-		// Limit upper bound
-		ps = ps > maxPageSize ? maxPageSize : ps;
 
 		Sort sort = sortResolver.resolveArgument(methodParameter, mavContainer, webRequest, binderFactory);
+		Pageable pageable = getPageable(methodParameter, page, pageSize);
 
-		return PageRequest.of(p, ps,
-				sort.isSorted() ? sort : defaultOrFallback.map(Pageable::getSort).orElseGet(Sort::unsorted));
-	}
-
-	/**
-	 * Returns the name of the request parameter to find the {@link Pageable} information in. Inspects the given
-	 * {@link MethodParameter} for {@link Qualifier} present and prefixes the given source parameter name with it.
-	 *
-	 * @param source the basic parameter name.
-	 * @param parameter the {@link MethodParameter} potentially qualified.
-	 * @return the name of the request parameter.
-	 */
-	protected String getParameterNameToUse(String source, @Nullable MethodParameter parameter) {
-
-		StringBuilder builder = new StringBuilder(prefix);
-
-		Qualifier qualifier = parameter == null ? null : parameter.getParameterAnnotation(Qualifier.class);
-
-		if (qualifier != null) {
-			builder.append(qualifier.value());
-			builder.append(qualifierDelimiter);
-		}
-
-		return builder.append(source).toString();
-	}
-
-	private Pageable getDefaultFromAnnotationOrFallback(MethodParameter methodParameter) {
-
-		PageableDefault defaults = methodParameter.getParameterAnnotation(PageableDefault.class);
-
-		if (defaults != null) {
-			return getDefaultPageRequestFrom(methodParameter, defaults);
-		}
-
-		return fallbackPageable;
-	}
-
-	private static Pageable getDefaultPageRequestFrom(MethodParameter parameter, PageableDefault defaults) {
-
-		Integer defaultPageNumber = defaults.page();
-		Integer defaultPageSize = getSpecificPropertyOrDefaultFromValue(defaults, "size");
-
-		if (defaultPageSize < 1) {
-			Method annotatedMethod = parameter.getMethod();
-			throw new IllegalStateException(String.format(INVALID_DEFAULT_PAGE_SIZE, annotatedMethod));
-		}
-
-		if (defaults.sort().length == 0) {
-			return PageRequest.of(defaultPageNumber, defaultPageSize);
+		if (sort.isSorted()) {
+			return PageRequest.of(pageable.getPageNumber(), pageable.getPageSize(), sort);
 		}
 
-		return PageRequest.of(defaultPageNumber, defaultPageSize, defaults.direction(), defaults.sort());
-	}
-
-	/**
-	 * Tries to parse the given {@link String} into an integer and applies the given boundaries. Will return 0 if the
-	 * {@link String} cannot be parsed.
-	 *
-	 * @param parameter the parameter value.
-	 * @param upper the upper bound to be applied.
-	 * @param shiftIndex whether to shift the index if {@link #oneIndexedParameters} is set to true.
-	 * @return
-	 */
-	private Optional<Integer> parseAndApplyBoundaries(@Nullable String parameter, int upper, boolean shiftIndex) {
-
-		if (!StringUtils.hasText(parameter)) {
-			return Optional.empty();
-		}
-
-		try {
-			int parsed = Integer.parseInt(parameter) - (oneIndexedParameters && shiftIndex ? 1 : 0);
-			return Optional.of(parsed < 0 ? 0 : parsed > upper ? upper : parsed);
-		} catch (NumberFormatException e) {
-			return Optional.of(0);
-		}
+		return pageable;
 	}
 }