Fix SonarCloud issues

.github/workflows/maven.yml

@@ -16,4 +16,4 @@ jobs:
       with:
         java-version: '11'
     - name: Build with Maven
-      run: mvn -B package --file pom.xml
+      run: mvn -B --no-transfer-progress clean verify --file pom.xml

src/main/java/com/suse/matcher/ConflictMatchMoveFilter.java

@@ -13,19 +13,13 @@
 /**
  * Filters ChangeMoves by only accepting those that do not lead to conflicts.
  */
-public class ConflictMatchMoveFilter implements SelectionFilter<Assignment, ChangeMove> {
-
-    /**
-     * Default constructor.
-     */
-    public ConflictMatchMoveFilter() {
-    }
+public class ConflictMatchMoveFilter implements SelectionFilter<Assignment, ChangeMove<Assignment>> {
 
     /**
      * {@inheritDoc}
      */
     @Override
-    public boolean accept(ScoreDirector<Assignment> director, ChangeMove move) {
+    public boolean accept(ScoreDirector<Assignment> director, ChangeMove<Assignment> move) {
         boolean confirmed = (Boolean) move.getPlanningValues().iterator().next();
 
         // we are confirming a Match
@@ -36,8 +30,8 @@ public boolean accept(ScoreDirector<Assignment> director, ChangeMove move) {
                 .collect(Collectors.toSet());
 
             // accept this Move only if no conflicting Match has been confirmed already
-            return !solution.getMatches().stream()
-                .anyMatch(m -> m.confirmed == Boolean.TRUE && conflictingIds.contains(m.id));
+            return solution.getMatches().stream()
+                .noneMatch(m -> m.confirmed == Boolean.TRUE && conflictingIds.contains(m.id));
         }
         else {
             // leaving a Match unconfirmed is always OK

src/main/java/com/suse/matcher/Drools.java

@@ -13,6 +13,7 @@
 import org.kie.api.runtime.KieSession;
 import org.kie.api.runtime.rule.Agenda;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashMap;
@@ -25,6 +26,9 @@
  * Deduces facts based on some base facts and rules defined ksession-rules.xml.
  */
 public class Drools {
+    /** Logger instance. */
+    private static final Logger LOGGER = LogManager.getLogger(Drools.class);
+
     /** Rule groups corresponding to filenames and agenda group names. */
     private static final String[] RULE_GROUPS = {
         "PartNumbers",
@@ -36,13 +40,10 @@ public class Drools {
     };
 
     /** Map to fact ids, see generateId(). */
-    private static Map<List<Object>, Integer> idMap = new HashMap<>();
-
-    /** Logger instance. */
-    private final Logger logger = LogManager.getLogger(Drools.class);
+    private static final Map<List<Object>, Integer> ID_MAP = new HashMap<>();
 
     /** Deduction resulting fact objects. */
-    private Collection<? extends Object> result;
+    private final Collection<Object> result;
 
     /**
      * Instantiates a Drools instance with the specified base facts.
@@ -88,18 +89,18 @@ public Drools(Collection<Object> baseFacts) {
         // start deduction engine
         long start = System.currentTimeMillis();
         session.fireAllRules();
-        logger.info("Deduction phase took {}ms", System.currentTimeMillis() - start);
+        LOGGER.info("Deduction phase took {}ms", System.currentTimeMillis() - start);
 
         // collect results
-        result = session.getObjects();
+        result = new ArrayList<>(session.getObjects());
 
         // log deducted messages
         result.stream()
             .filter(o -> o instanceof Message)
             .map(m -> (Message) m)
             .filter(m -> m.severity.equals(Message.Level.DEBUG))
             .sorted()
-            .forEach(m -> logger.debug("{}: {}", m.type, m.data.toString()))
+            .forEach(m -> LOGGER.debug("{}: {}", m.type, m.data))
         ;
 
         // cleanup
@@ -111,15 +112,15 @@ public Drools(Collection<Object> baseFacts) {
      * Returns all facts deduced by Drools.
      * @return the deduced facts
      */
-    public Collection<? extends Object> getResult() {
+    public Collection<Object> getResult() {
         return result;
     }
 
     /**
      * reset the idMap
      */
     public static void resetIdMap() {
-        idMap.clear();
+        ID_MAP.clear();
     }
 
     /**
@@ -131,10 +132,6 @@ public static void resetIdMap() {
      * @return a new id
      */
     public static int generateId(Object... objects) {
-        List<Object> listOfData = Arrays.asList(objects);
-        if (!idMap.containsKey(listOfData)) {
-            idMap.put(listOfData, idMap.size());
-        }
-        return idMap.get(listOfData);
+        return ID_MAP.computeIfAbsent(Arrays.asList(objects), k -> ID_MAP.size());
     }
 }

src/main/java/com/suse/matcher/FactConverter.java

@@ -1,10 +1,5 @@
 package com.suse.matcher;
 
-import static java.util.stream.Collectors.groupingBy;
-import static java.util.stream.Collectors.mapping;
-import static java.util.stream.Collectors.toList;
-import static java.util.stream.Collectors.toSet;
-
 import com.suse.matcher.facts.CentGroup;
 import com.suse.matcher.facts.HostGuest;
 import com.suse.matcher.facts.InstalledProduct;
@@ -47,14 +42,18 @@
  */
 public class FactConverter {
 
+    private FactConverter() {
+        // Prevent instantiation
+    }
+
     /**
      * Converts JSON objects to facts (inputs to the rule engine).
      *
      * @param input a JSON input data blob
      * @return a collection of facts
      */
     public static Collection<Object> convertToFacts(JsonInput input) {
-        Collection<Object> result = new LinkedList<Object>();
+        Collection<Object> result = new LinkedList<>();
 
         result.add(new Timestamp(input.getTimestamp()));
 
@@ -114,8 +113,9 @@ public static Collection<Object> convertToFacts(JsonInput input) {
      * @return the output
      */
     public static JsonOutput convertToOutput(Assignment assignment) {
-        Date timestamp = assignment.getProblemFactStream(Timestamp.class)
-                .findFirst().get().timestamp;
+        Date timestamp = assignment.getProblemFactStream(Timestamp.class).findFirst()
+            .map(Timestamp::getTimestamp)
+            .orElse(new Date());
 
         List<JsonMatch> matches = getMatches(assignment);
 
@@ -155,7 +155,7 @@ public static List<JsonMatch> getMatches(Assignment assignment) {
         Set<Integer> confirmedGroupIds = assignment.getMatches().stream()
                 .filter(m -> m.confirmed)
                 .map(m -> m.id)
-                .collect(toSet());
+                .collect(Collectors.toSet());
 
         // map of cent group id -> cent group cents
         Map<Number, Integer> centGroupsCents = assignment.getProblemFactStream(CentGroup.class)
@@ -188,7 +188,7 @@ public static List<JsonMatch> getMatches(Assignment assignment) {
                 .append(a.getCents(), b.getCents())
                 .toComparison()
             )
-            .collect(toList());
+            .collect(Collectors.toList());
     }
 
     /**
@@ -199,11 +199,14 @@ public static List<JsonMatch> getMatches(Assignment assignment) {
      */
     private static List<JsonSubscription> getSubscriptions(Assignment assignment) {
         Map<Long, Set<Long>> subProducts = assignment.getProblemFactStream(SubscriptionProduct.class)
-                .collect(groupingBy(sp -> sp.subscriptionId, mapping(sp -> sp.productId, Collectors.toCollection(() -> new TreeSet<>()))));
+                .collect(Collectors.groupingBy(
+                    sp -> sp.subscriptionId,
+                    Collectors.mapping(sp -> sp.productId, Collectors.toCollection(() -> new TreeSet<>()))
+                ));
         return assignment.getProblemFactStream(Subscription.class)
                 .sorted(Comparator.comparing(Subscription::getId))
                 .map(s -> new JsonSubscription(s.id, s.partNumber, s.name, s.quantity, s.startDate, s.endDate,
                         s.sccUsername, subProducts.get(s.id)))
-                .collect(toList());
+                .collect(Collectors.toList());
     }
 }

src/main/java/com/suse/matcher/JsonIO.java

@@ -1,28 +1,28 @@
 package com.suse.matcher;
 
-import static com.google.gson.FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES;
+import com.suse.matcher.json.JsonInput;
+import com.suse.matcher.json.JsonOutput;
 
+import com.google.gson.FieldNamingPolicy;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.JsonIOException;
 import com.google.gson.JsonSyntaxException;
 import com.google.gson.reflect.TypeToken;
-import com.suse.matcher.json.JsonInput;
-import com.suse.matcher.json.JsonOutput;
 
 /**
  * Serializes and deserializes objects from and to JSON.
  */
 public class JsonIO {
 
     /** Deserializer instance. */
-    private Gson gson;
+    private final Gson gson;
 
     /** Default constructor. */
     public JsonIO() {
         gson = new GsonBuilder()
             .setDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSX")
-            .setFieldNamingPolicy(LOWER_CASE_WITH_UNDERSCORES)
+            .setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)
             .setPrettyPrinting()
             .create();
     }

src/main/java/com/suse/matcher/Main.java

@@ -1,9 +1,5 @@
 package com.suse.matcher;
 
-import static java.util.Optional.empty;
-import static java.util.Optional.of;
-import static java.util.Optional.ofNullable;
-
 import com.suse.matcher.json.JsonInput;
 import com.suse.matcher.solver.Assignment;
 
@@ -18,6 +14,8 @@
 import org.apache.logging.log4j.core.LoggerContext;
 
 import java.io.File;
+import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.nio.charset.Charset;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -32,27 +30,26 @@ public class Main {
      * The main method.
      *
      * @param args command line arguments
-     * @throws Exception if anything unexpected happens
      */
-    public static final void main(String[] args) throws Exception {
+    public static void main(String[] args) {
         long start = System.currentTimeMillis();
         CommandLine commandLine = parseCommandLine(args);
 
         // First initialize the logging system
         Optional<Level> logLevel = commandLine.hasOption('v') ?
-            of(Level.toLevel(commandLine.getOptionValue('v'))) :
-            empty();
+            Optional.of(Level.toLevel(commandLine.getOptionValue('v'))) :
+            Optional.empty();
 
-        try (LoggerContext context = Log4J.initialize(logLevel, ofNullable(commandLine.getOptionValue('l')))) {
+        try (LoggerContext context = Log4J.initialize(logLevel, Optional.ofNullable(commandLine.getOptionValue('l')))) {
             Logger logger = context.getLogger(Main.class);
             logger.info("Starting subscription-matcher process");
 
             try {
                 // create output writing objects
                 Optional<Character> delimiter = commandLine.hasOption('d') ?
-                    of(commandLine.getOptionValue('d').charAt(0)) :
-                    empty();
-                Optional<String> outdir = ofNullable(commandLine.getOptionValue('o'));
+                    Optional.of(commandLine.getOptionValue('d').charAt(0)) :
+                    Optional.empty();
+                Optional<String> outdir = Optional.ofNullable(commandLine.getOptionValue('o'));
                 OutputWriter writer = new OutputWriter(outdir, delimiter);
 
                 // load input data
@@ -72,8 +69,13 @@ public static final void main(String[] args) throws Exception {
 
                 logger.info("Whole execution took {}ms", System.currentTimeMillis() - start);
             }
-            catch (Exception ex) {
-                logger.error("Unexpected exception: ", ex);
+            catch (IOException ex) {
+                logger.error("Unexpected I/O error", ex);
+                throw new UncheckedIOException(ex);
+            }
+            catch (RuntimeException ex) {
+                logger.error("Unexpected error", ex);
+                throw ex;
             }
         }
     }