Fix compatibility issue

src/org/ohdsi/usagi/Concept.java

@@ -77,4 +77,13 @@ public static Concept createEmptyConcept() {
 
 	public Concept() {
 	}
+
+	@Override
+	public boolean equals(Object o) {
+		// Only compare conceptId
+		if (this == o) return true;
+		if (o == null || getClass() != o.getClass()) return false;
+		Concept concept = (Concept) o;
+		return conceptId == concept.conceptId;
+	}
 }

src/org/ohdsi/usagi/MappingTarget.java

@@ -15,6 +15,8 @@
  ******************************************************************************/
 package org.ohdsi.usagi;
 
+import java.util.Objects;
+
 /**
  * Class for holding information about a single (target) concept in the Vocabulary
  */
@@ -72,4 +74,14 @@ public Type getMappingType() {
 	public void setMappingType(Type mappingType) {
 		this.mappingType = mappingType;
 	}
+
+	@Override
+	public boolean equals(Object o) {
+		// Only compares target concept and mappingType.
+		if (this == o) return true;
+		if (o == null || getClass() != o.getClass()) return false;
+		MappingTarget that = (MappingTarget) o;
+		return Objects.equals(concept, that.concept) && mappingType == that.mappingType;
+	}
+
 }

src/org/ohdsi/usagi/ReadCodeMappingsFromFile.java

@@ -77,14 +77,18 @@ && new SourceCode(row).sourceName.equals(buffer.getSourceCode().sourceName)) {
 							buffer.setMappingStatus(MappingStatus.INVALID_TARGET);
 							buffer.setComment("Invalid existing target: " + row.get("conceptId"));
 						} else {
-							// Type and provenance might not be available in older Usagi files
+							String mappingTypeString = row.get("mappingType", "MAPS_TO");
+							if (!mappingTypeString.startsWith("MAPS_TO")) {
+								// For backwards compatibility with files using event/value/unit
+								mappingTypeString = mappingTypeString
+										.replace("EVENT", "MAPS_TO")
+										.replace("VALUE", "MAPS_TO_VALUE")
+										.replace("UNIT", "MAPS_TO_UNIT");
+							}
+
 							MappingTarget mappingTarget = new MappingTarget(
 									concept,
-									MappingTarget.Type.valueOf(row.get("mappingType", "MAPS_TO")
-											.replace("EVENT", "MAPS_TO")
-											.replace("VALUE", "MAPS_TO_VALUE")
-											.replace("UNIT", "MAPS_TO_UNIT")
-									),
+									MappingTarget.Type.valueOf(mappingTypeString),
 									row.get("createdBy", ""),
 									row.getLong("createdOn", "0")
 							);

src/org/ohdsi/usagi/ui/actions/ApplyPreviousMappingAction.java

@@ -63,9 +63,11 @@ public void actionPerformed(ActionEvent arg0) {
 			mappingToBeApplied.loadFromFile(file.getAbsolutePath());
 
 			// Apply mapping. Add mappings not currently present
+			ApplyPreviousChangeSummary summary = new ApplyPreviousChangeSummary();
 			for (CodeMapping codeMappingToBeApplied : mappingToBeApplied) {
 				CodeMapping existingMapping = codeToMapping.get(codeMappingToBeApplied.getSourceCode().sourceCode);
 				if (existingMapping != null) {
+					summary.compare(existingMapping, codeMappingToBeApplied);
 					existingMapping.getSourceCode().sourceName = codeMappingToBeApplied.getSourceCode().sourceName;
 					existingMapping.setTargetConcepts(codeMappingToBeApplied.getTargetConcepts());
 					existingMapping.setMappingStatus(codeMappingToBeApplied.getMappingStatus());
@@ -82,7 +84,7 @@ public void actionPerformed(ActionEvent arg0) {
 			}
 
 			String message = "The applied mapping contained " + mappingToBeApplied.size() + " mappings of which " + mappingsApplied
-					+ " were applied to the current mapping and " + mappingsAdded + " were newly added.";
+					+ " were applied to the current mapping and " + mappingsAdded + " were newly added.\n\n" + summary.createReport();
 			Global.mappingTablePanel.updateUI();
 			Global.mappingDetailPanel.updateUI();
 			Global.mapping.fireDataChanged(APPROVE_EVENT); // To update the footer
@@ -91,7 +93,48 @@ public void actionPerformed(ActionEvent arg0) {
 				Global.usagiSearchEngine.createDerivedIndex(Global.mapping.getSourceCodes(), Global.frame);
 				Global.mappingDetailPanel.doSearch();
 			}
-			JOptionPane.showMessageDialog(Global.frame, message);
+			JOptionPane.showMessageDialog(Global.frame, message, "Summary", JOptionPane.INFORMATION_MESSAGE);
+		}
+	}
+
+	private static class ApplyPreviousChangeSummary {
+		private int nChanged = 0;
+		private int nSourceNameChanged = 0;
+		private int nTargetConceptsChanged = 0;
+		private int nMappingStatusChanged = 0;
+		private int nEquivalenceChanged = 0;
+
+		private void compare(CodeMapping A, CodeMapping B) {
+			boolean hasChanged = false;
+			if (!A.getSourceCode().sourceName.equals(B.getSourceCode().sourceName)) {
+				nSourceNameChanged++;
+				hasChanged = true;
+			}
+			if (!A.getTargetConcepts().equals(B.getTargetConcepts())) {
+				nTargetConceptsChanged++; // This could be target concept, size OR type
+				hasChanged = true;
+			}
+			if (!A.getMappingStatus().equals(B.getMappingStatus())) {
+				nMappingStatusChanged++;
+				hasChanged = true;
+			}
+			if (!A.getEquivalence().equals(B.getEquivalence())) {
+				nEquivalenceChanged++;
+				hasChanged = true;
+			}
+			if (hasChanged) {
+				nChanged++;
+			}
+		}
+
+		private String createReport() {
+			StringBuilder report = new StringBuilder();
+			report.append("Of the applied mappings, " + nChanged + " mappings changed.");
+			report.append("\n\tSource name: " + nSourceNameChanged);
+			report.append("\n\tTarget concept: " + nTargetConceptsChanged + "\t(changed target concept, target type AND/OR number of targets)");
+			report.append("\n\tMapping status: " + nMappingStatusChanged);
+			report.append("\n\tMapping equivalence: " + nEquivalenceChanged);
+			return report.toString();
 		}
 	}
 }