DATAREST-957 - Polish most critical Sonar warnings.

Fixed broken equals(…) in ProjectionDefinition. Switched to iterating over Map's entry set instead of the keys. Made UriAwareHttpServletRequest static.

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/BasePathAwareHandlerMapping.java

@@ -190,7 +190,7 @@ public class BasePathAwareHandlerMapping extends RequestMappingHandlerMapping {
 		super.afterPropertiesSet();
 	}
 
-	private class UriAwareHttpServletRequest implements HttpServletRequest {
+	private static class UriAwareHttpServletRequest implements HttpServletRequest {
 
 		private final ServletContext context;
 		private final String path;

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/RepositoryPropertyReferenceController.java

@@ -382,10 +382,13 @@ class RepositoryPropertyReferenceController extends AbstractRepositoryRestContro
 						}
 					}
 				} else if (prop.property.isMap()) {
+
 					Map<Object, Object> m = (Map<Object, Object>) prop.propertyValue;
-					Iterator<Object> itr = m.keySet().iterator();
+					Iterator<Entry<Object, Object>> itr = m.entrySet().iterator();
+
 					while (itr.hasNext()) {
-						Object key = itr.next();
+
+						Object key = itr.next().getKey();
 
 						IdentifierAccessor accessor = prop.entity.getIdentifierAccessor(m.get(key));
 						String s = accessor.getIdentifier().toString();
@@ -394,6 +397,7 @@ class RepositoryPropertyReferenceController extends AbstractRepositoryRestContro
 							itr.remove();
 						}
 					}
+
 				} else {
 					prop.accessor.setProperty(prop.property, null);
 				}

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/config/QuerydslAwareRootResourceInformationHandlerMethodArgumentResolver.java

@@ -17,6 +17,7 @@ package org.springframework.data.rest.webmvc.config;
 
 import java.util.Arrays;
 import java.util.Map;
+import java.util.Map.Entry;
 
 import org.springframework.core.MethodParameter;
 import org.springframework.data.querydsl.QueryDslPredicateExecutor;
@@ -103,8 +104,8 @@ class QuerydslAwareRootResourceInformationHandlerMethodArgumentResolver
 
 		MultiValueMap<String, String> result = new LinkedMultiValueMap<String, String>();
 
-		for (String key : source.keySet()) {
-			result.put(key, Arrays.asList(source.get(key)));
+		for (Entry<String, String[]> entry : source.entrySet()) {
+			result.put(entry.getKey(), Arrays.asList(entry.getValue()));
 		}
 
 		return result;