prevent filename duplicates from "edit metadata for files" page #6574

src/main/java/edu/harvard/iq/dataverse/EditDatafilesPage.java

@@ -72,6 +72,7 @@
 import org.apache.commons.httpclient.methods.GetMethod;
 import java.text.DateFormat;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Set;
 import java.util.logging.Level;
 import javax.faces.event.AjaxBehaviorEvent;
@@ -1094,6 +1095,11 @@ public String saveReplacementFile() throws FileReplaceException{
     }    
 
     public String save() {
+        Collection<String> duplicates = IngestUtil.findDuplicateFilenames(workingVersion);
+        if (!duplicates.isEmpty()) {
+            JH.addMessage(FacesMessage.SEVERITY_ERROR, BundleUtil.getStringFromBundle("dataset.message.filesFailure"), BundleUtil.getStringFromBundle("dataset.message.editMetadata.duplicateFilenames", new ArrayList<>(duplicates)));
+            return null;
+        }
         if (!saveEnabled) {
             return "";
         }

src/main/java/edu/harvard/iq/dataverse/ingest/IngestUtil.java

@@ -30,6 +30,7 @@
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
@@ -141,6 +142,39 @@ public static boolean conflictsWithExistingFilenames(String label, String direct
         return false;
     }
 
+    /**
+     * Given a DatasetVersion, iterate across all the files (including their
+     * paths) and return any duplicates.
+     *
+     * @param datasetVersion
+     * @return A Collection of Strings in the form of path/to/file.txt
+     */
+    public static Collection<String> findDuplicateFilenames(DatasetVersion datasetVersion) {
+        List<String> allFileNamesWithPaths = new ArrayList<>();
+        for (FileMetadata fileMetadata : datasetVersion.getFileMetadatas()) {
+            String directoryLabel = fileMetadata.getDirectoryLabel();
+            String path = "";
+            if (directoryLabel != null) {
+                path = directoryLabel + "/";
+            }
+            String pathAndfileName = path + fileMetadata.getLabel();
+            allFileNamesWithPaths.add(pathAndfileName);
+        }
+        return findDuplicates(allFileNamesWithPaths);
+    }
+
+    // https://stackoverflow.com/questions/7414667/identify-duplicates-in-a-list
+    private static <T> Set<T> findDuplicates(Collection<T> collection) {
+        Set<T> duplicates = new HashSet<>();
+        Set<T> uniques = new HashSet<>();
+        for (T t : collection) {
+            if (!uniques.add(t)) {
+                duplicates.add(t);
+            }
+        }
+        return duplicates;
+    }
+
     // This method is called on a single file, when we need to modify the name 
     // of an already ingested/persisted datafile. For ex., when we have converted
     // a file to tabular data, and want to update the extension accordingly. 

src/main/java/propertyFiles/Bundle.properties

@@ -1358,6 +1358,7 @@ dataset.message.uploadFilesSingle.message=For more information about supported f
 dataset.message.uploadFilesMultiple.message=Multiple file upload/download methods are available for this dataset. Once you upload a file using one of these methods, your choice will be locked in for this dataset.
 dataset.message.editMetadata.label=Edit Dataset Metadata
 dataset.message.editMetadata.message=Add more metadata about this dataset to help others easily find it.
+dataset.message.editMetadata.duplicateFilenames=Duplicate filenames: {0}
 dataset.message.editTerms.label=Edit Dataset Terms
 dataset.message.editTerms.message=Add the terms of use for this dataset to explain how to access and use your data.
 dataset.message.locked.editNotAllowedInReview=Dataset cannot be edited due to In Review dataset lock.