MCR-3248 PMD rule UnnecessaryCast (#2409)

Author: toKrause

mycore-base/src/main/java/org/mycore/common/MCRCache.java

@@ -249,7 +249,7 @@ public boolean isEmpty() {
      * @return the fill rate of this cache as double value
      */
     public double getFillRate() {
-        return capacity == 0 ? 1.0 : (double) getCurrentSize() / (double) capacity;
+        return capacity == 0 ? 1.0 : (double) getCurrentSize() / capacity;
     }
 
     /**

mycore-base/src/main/java/org/mycore/frontend/fileupload/MCRUploadHandlerIFS.java

@@ -242,7 +242,7 @@ public synchronized long receiveFile(String path, InputStream in, long length, S
                 }
             });
             this.filesUploaded++;
-            int progress = (int) (((float) this.filesUploaded / (float) getNumFiles()) * 100f);
+            int progress = (int) (((float) this.filesUploaded / getNumFiles()) * 100f);
             this.setProgress(progress);
         }
     }

mycore-base/src/main/java/org/mycore/frontend/jersey/resources/MCRJerseyExceptionMapper.java

@@ -108,22 +108,40 @@ public Response toResponse(Exception exc) {
 
     private Response getResponse(Exception exc) {
         if (exc instanceof WebApplicationException wae) {
-            Response response = wae.getResponse();
-            if (response.hasEntity()) {
-                return response;
-            }
-            return Response.fromResponse(response)
-                .entity(exc.getMessage())
+            return getResponse(wae);
+        }
+
+        String message = exc.getMessage();
+        boolean hasMessage = message != null;
+        boolean isFormRequest = isFormRequest();
+
+        Object entity = isFormRequest && hasMessage ? message : new MCRExceptionContainer(exc);
+        return Response.status(Status.INTERNAL_SERVER_ERROR).entity(entity).build();
+    }
+
+    private static Response getResponse(WebApplicationException wae) {
+        Response response = wae.getResponse();
+        if (!response.hasEntity()) {
+            response = Response
+                .fromResponse(response)
+                .entity(wae.getMessage())
                 .type(MediaType.TEXT_PLAIN_TYPE)
                 .build();
         }
-        Object entity = Optional.ofNullable(request.getContentType())
+        return response;
+    }
+    
+    private boolean isFormRequest() {
+        return Optional
+            .ofNullable(request.getContentType())
             .map(MediaType::valueOf)
-            .filter(t -> t.isCompatible(MediaType.APPLICATION_FORM_URLENCODED_TYPE) || t
-                .isCompatible(MediaType.MULTIPART_FORM_DATA_TYPE))
-            .map(t -> (Object) exc.getMessage()) //do not container form requests responses
-            .orElseGet(() -> new MCRExceptionContainer(exc));
-        return Response.status(Status.INTERNAL_SERVER_ERROR).entity(entity).build();
+            .stream()
+            .anyMatch(MCRJerseyExceptionMapper::isFormRequestMediaType);
+    }
+
+    private static boolean isFormRequestMediaType(MediaType mediaType) {
+        return mediaType.isCompatible(MediaType.APPLICATION_FORM_URLENCODED_TYPE)
+            || mediaType.isCompatible(MediaType.MULTIPART_FORM_DATA_TYPE);
     }
 
     @XmlRootElement(name = "error")

mycore-oai/src/main/java/org/mycore/oai/MCROAISetManager.java

@@ -234,7 +234,7 @@ private MCRSet createSet(String setId, Element setElement) {
                 .stream() //all setDescription
                 .flatMap(e -> e.getChildren().stream().limit(1)) //first childElement of setDescription
                 .peek(Element::detach)
-                .map(d -> (Description) new Description() {
+                .map(d -> new Description() {
                     @Override
                     public Element toXML() {
                         return d;

mycore-orcid2/src/main/java/org/mycore/orcid2/v3/work/MCRORCIDWorkSummaryUtils.java

@@ -121,7 +121,7 @@ private static boolean checkPutCodeExistsInSummaries(List<WorkSummary> works, lo
 
     private static long[] getPutCodesNotCreatedByThisAppFromSummaries(Stream<WorkSummary> works) {
         return works.filter(w -> !MCRORCIDUtils.isCreatedByThisApplication(w.retrieveSourcePath()))
-            .map(WorkSummary::getPutCode).mapToLong(l -> (long) l).toArray();
+            .map(WorkSummary::getPutCode).mapToLong(Long::longValue).toArray();
     }
 
     private static long getPutCodeCreatedByThisAppFromSummaries(Stream<WorkSummary> works) {

mycore-solr/src/main/java/org/mycore/solr/index/statistic/MCRSolrIndexStatistic.java

@@ -73,7 +73,7 @@ public synchronized double reset() {
                 if (docs == 0) {
                     return time == 0 ? 0 : Double.MAX_VALUE;
                 }
-                return ((double) time / (double) docs);
+                return (double) time / docs;
             }
         }
     }

mycore-sword/src/main/java/org/mycore/sword/MCRSwordUtil.java

@@ -556,7 +556,7 @@ public static String buildCollectionPaginationLinkHref(String collection, Intege
          */
         public static void addPaginationLinks(IRI collectionIRI, String collection, Feed feed,
             MCRSwordCollectionProvider collectionProvider) throws SwordServerException {
-            final int lastPage = (int) Math.ceil((double) collectionProvider.getIDSupplier().getCount()
+            final int lastPage = (int) Math.ceil(collectionProvider.getIDSupplier().getCount()
                 / (double) MCRSwordConstants.MAX_ENTRYS_PER_PAGE);
             int currentPage = ParseLinkUtil.CollectionIRI.getPaginationFromCollectionIRI(collectionIRI);
 

ruleset.xml

@@ -108,8 +108,12 @@
   <rule ref="category/java/codestyle.xml/PackageCase"/>
   <rule ref="category/java/codestyle.xml/UnnecessaryAnnotationValueElement"/>
   <rule ref="category/java/codestyle.xml/UnnecessaryBoxing"/>
-  <!-- TODO: Create PR to fix this rule -->
   <!--
+  Rule remains inactive due to two known bugs in PMD:
+   - https://github.com/pmd/pmd/issues/5523
+   - https://github.com/pmd/pmd/issues/5440
+  Both bugs should be resolved in PMD 7.11.
+  TODO: Activate rule, once we use PMD 7.11 or later.
   <rule ref="category/java/codestyle.xml/UnnecessaryCast"/>
   -->
   <rule ref="category/java/codestyle.xml/UnnecessaryConstructor"/>