feat: Create pagination annotation

Resolves #19 (closed)

core/src/main/java/org/eclipsefoundation/core/response/PaginatedResultsFilter.java

@@ -6,12 +6,14 @@
 * which is available at https://www.eclipse.org/legal/epl-2.0/
 *
 * Author: Martin Lowe <martin.lowe@eclipse-foundation.org>
+*       Zachary Sabourin <zachary.sabourin@eclipse-foundation.org>
 *
 * SPDX-License-Identifier: EPL-2.0
 **********************************************************************/
 package org.eclipsefoundation.core.response;
 
 import java.io.IOException;
+import java.lang.reflect.Method;
 import java.util.List;
 import java.util.Set;
 import java.util.TreeSet;
@@ -23,6 +25,7 @@ import javax.servlet.http.HttpServletResponse;
 import javax.ws.rs.container.ContainerRequestContext;
 import javax.ws.rs.container.ContainerResponseContext;
 import javax.ws.rs.container.ContainerResponseFilter;
+import javax.ws.rs.container.ResourceInfo;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MultivaluedMap;
 import javax.ws.rs.core.UriBuilder;
@@ -39,11 +42,13 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Adds pagination and Link headers to the response by slicing the response entity if its a list entity. This will not
+ * Adds pagination and Link headers to the response by slicing the response
+ * entity if its a list entity. This will not
  * dig into complex entities to avoid false positives.
  *
  * @author Martin Lowe
  */
+
 @Provider
 @Priority(5)
 public class PaginatedResultsFilter implements ContainerResponseFilter {
@@ -69,12 +74,19 @@ public class PaginatedResultsFilter implements ContainerResponseFilter {
 
     @Context
     HttpServletResponse response;
+    @Context
+    ResourceInfo resourceInfo;
 
     @Override
     public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext)
             throws IOException {
-        if (enablePagination.get()) {
+
+        Method method = resourceInfo.getResourceMethod();
+        Pagination annotation = method.getAnnotation(Pagination.class);
+
+        if ((annotation == null || annotation.value()) && enablePagination.get()) {
             Object entity = responseContext.getEntity();
+
             // only try and paginate if there are multiple entities
             if (entity instanceof Set) {
                 paginateResults(responseContext,
@@ -108,10 +120,11 @@ public class PaginatedResultsFilter implements ContainerResponseFilter {
     }
 
     /**
-     * Gets a header value if available, checking first the servlet response then the mutable response wrapper.
+     * Gets a header value if available, checking first the servlet response then
+     * the mutable response wrapper.
      * 
      * @param responseContext the mutable response wrapper
-     * @param headerName the header to retrieve
+     * @param headerName      the header to retrieve
      * @return the header value if set, null otherwise.
      */
     private String getResponseHeader(ContainerResponseContext responseContext, String headerName) {
@@ -142,10 +155,13 @@ public class PaginatedResultsFilter implements ContainerResponseFilter {
     }
 
     /**
-     * Gets the current requested page, rounding down to max if larger than the max page number, and up if below 1.
+     * Gets the current requested page, rounding down to max if larger than the max
+     * page number, and up if below 1.
      *
-     * @param listEntity list entity used to determine the number of pages present for current call.
-     * @return the current page number if set, the last page if greater, or 1 if not set or negative.
+     * @param listEntity list entity used to determine the number of pages present
+     *                   for current call.
+     * @return the current page number if set, the last page if greater, or 1 if not
+     *         set or negative.
      */
     private int getRequestedPage(int maxSize, int pageSize) {
         MultivaluedMap<String, String> params = getUriInfo().getQueryParameters();
@@ -167,7 +183,8 @@ public class PaginatedResultsFilter implements ContainerResponseFilter {
     }
 
     /**
-     * Allows for external bindings to affect the current page size, defaulting to the internal set configuration.
+     * Allows for external bindings to affect the current page size, defaulting to
+     * the internal set configuration.
      * 
      * @param responseContext
      * @return
@@ -185,7 +202,8 @@ public class PaginatedResultsFilter implements ContainerResponseFilter {
     }
 
     /**
-     * Returns the max page size as defined by internal metrics (ignoring pagesize params).
+     * Returns the max page size as defined by internal metrics (ignoring pagesize
+     * params).
      * 
      * @return the internal max page size.
      */
@@ -201,11 +219,12 @@ public class PaginatedResultsFilter implements ContainerResponseFilter {
     }
 
     /**
-     * Builds an href for a paginated link using the BaseUri UriBuilder from the UriInfo object, replacing just the page
+     * Builds an href for a paginated link using the BaseUri UriBuilder from the
+     * UriInfo object, replacing just the page
      * query parameter.
      *
      * @param builder base URI builder from the UriInfo object.
-     * @param page the page to link to in the returned link
+     * @param page    the page to link to in the returned link
      * @return fully qualified HREF for the paginated results
      */
     private String buildHref(UriBuilder builder, int page) {
@@ -219,9 +238,10 @@ public class PaginatedResultsFilter implements ContainerResponseFilter {
      * Gets an int bound by the size of a list.
      *
      * @param list the list to bind the number by
-     * @param num the number to check for exceeding bounds.
-     * @return the passed number if its within the size of the given array, 0 if the number is negative, and the array
-     * size if greater than the maximum bounds.
+     * @param num  the number to check for exceeding bounds.
+     * @return the passed number if its within the size of the given array, 0 if the
+     *         number is negative, and the array
+     *         size if greater than the maximum bounds.
      */
     private int getArrayLimitedNumber(List<?> list, int num) {
         return Math.min(list.size(), Math.max(0, num));