#470: fix various warnings

Author: mmerdes

oshdb-api/src/main/java/org/heigit/ohsome/oshdb/api/db/H2Support.java

@@ -4,6 +4,9 @@
 
 public class H2Support {
 
+  private H2Support() {
+  }
+
   public static String pathToUrl(Path path) {
     var absolutePath = path.toAbsolutePath().toString();
     absolutePath = absolutePath.replaceAll("\\.mv\\.db$", "");

oshdb-api/src/main/java/org/heigit/ohsome/oshdb/api/db/OSHDBJdbc.java

@@ -135,5 +135,6 @@ public boolean multithreading() {
 
   @Override
   public void close() throws Exception {
+    //nothing to do
   }
 }

oshdb-api/src/test/java/org/heigit/ohsome/oshdb/api/tests/HelpersOSMContributionViewTest.java

@@ -1,6 +1,7 @@
 package org.heigit.ohsome.oshdb.api.tests;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
 
 import java.util.EnumSet;
 import java.util.HashSet;
@@ -32,11 +33,11 @@ class HelpersOSMContributionViewTest {
 
   private static final double DELTA = 1e-8;
 
-  HelpersOSMContributionViewTest() throws Exception {
+  HelpersOSMContributionViewTest() {
     oshdb = new OSHDBH2("../data/test-data");
   }
 
-  private MapReducer<OSMContribution> createMapReducer() throws Exception {
+  private MapReducer<OSMContribution> createMapReducer() {
     return OSMContributionView
         .on(oshdb)
         .areaOfInterest(bbox)
@@ -85,7 +86,7 @@ void testSum() throws Exception {
         .sum(contribution -> 1);
 
     assertEquals(42, result4.get(EnumSet.of(ContributionType.CREATION).toString()));
-    assertEquals(null, result4.get(EnumSet.of(ContributionType.DELETION).toString()));
+    assertNull(result4.get(EnumSet.of(ContributionType.DELETION).toString()));
   }
 
   @Test
@@ -135,7 +136,7 @@ void testAverage() throws Exception {
             contribution.getContributionTypes().contains(ContributionType.TAG_CHANGE) ? 1 : 0)
         .average();
 
-    assertEquals(1.0, result1.doubleValue(), DELTA);
+    assertEquals(1.0, result1, DELTA);
 
     // many timestamps
     SortedMap<OSHDBTimestamp, Double> result2 = this.createMapReducer()
@@ -161,7 +162,7 @@ void testAverage() throws Exception {
             .contains(ContributionType.CREATION))
         .average(contribution -> contribution.getEntityAfter().getId() % 2);
 
-    assertEquals(0.5, result4.get(true).doubleValue(), DELTA);
+    assertEquals(0.5, result4.get(true), DELTA);
   }
 
   @Test
@@ -174,7 +175,7 @@ void testWeightedAverage() throws Exception {
             2 * (contribution.getEntityAfter().getId() % 2)
         ));
 
-    assertEquals(1.0, result1.doubleValue(), DELTA);
+    assertEquals(1.0, result1, DELTA);
 
     // many timestamps
     SortedMap<OSHDBTimestamp, Double> result2 = this.createMapReducer()
@@ -203,7 +204,7 @@ void testWeightedAverage() throws Exception {
             2 * (contribution.getEntityAfter().getId() % 2)
         ));
 
-    assertEquals(1.0, result4.get(true).doubleValue(), DELTA);
+    assertEquals(1.0, result4.get(true), DELTA);
   }
 
   @Test
@@ -252,7 +253,7 @@ void testUniq() throws Exception {
         .timestamps(timestamps2)
         .map(x -> null)
         .uniq();
-    assertEquals(result5.size(), 1);
+    assertEquals(1, result5.size() );
   }
 
 }

oshdb-api/src/test/java/org/heigit/ohsome/oshdb/api/tests/MapAggregateByGeometryTest.java

@@ -39,18 +39,18 @@ class MapAggregateByGeometryTest {
 
   private static final double DELTA = 1e-4;
 
-  MapAggregateByGeometryTest() throws Exception {
+  MapAggregateByGeometryTest() {
     oshdb = new OSHDBH2("../data/test-data");
   }
 
-  private MapReducer<OSMContribution> createMapReducerOSMContribution() throws Exception {
+  private MapReducer<OSMContribution> createMapReducerOSMContribution() {
     return OSMContributionView
         .on(oshdb)
         .areaOfInterest(bbox)
         .filter("type:way and highway=*");
   }
 
-  private MapReducer<OSMEntitySnapshot> createMapReducerOSMEntitySnapshot() throws Exception {
+  private MapReducer<OSMEntitySnapshot> createMapReducerOSMEntitySnapshot() {
     return OSMEntitySnapshotView
         .on(oshdb)
         .areaOfInterest(bbox)
@@ -205,13 +205,13 @@ void testCombinedWithAggregateByTimestampOrder() throws Exception {
 
   @SuppressWarnings("ResultOfMethodCallIgnored") //  we test for a thrown exception here
   @Test()
-  void testCombinedWithAggregateByTimestampUnsupportedOrder3() throws Exception {
-    assertThrows(UnsupportedOperationException.class, () -> {
+  void testCombinedWithAggregateByTimestampUnsupportedOrder3() {
+    assertThrows(UnsupportedOperationException.class, () ->
       createMapReducerOSMEntitySnapshot()
           .timestamps(timestamps1)
           .groupByEntity()
           .aggregateByGeometry(getSubRegions())
-          .collect();
-    });
+          .collect()
+    );
   }
 }

oshdb-util/src/main/java/org/heigit/ohsome/oshdb/util/tagtranslator/JdbcTagTranslator.java

@@ -29,8 +29,8 @@ public class JdbcTagTranslator implements TagTranslator {
       + " where k.txt = ? and kv.txt = any (?)", TableNames.E_KEY, TableNames.E_KEYVALUE);
 
   private static final String OSHDB_OSM_KEY = String.format("SELECT txt, id"
-          + " from %s"
-          + " where id = any(?)", TableNames.E_KEY);
+      + " from %s"
+      + " where id = any(?)", TableNames.E_KEY);
 
   private static final String OSHDB_OSM_TAG = String.format("SELECT txt, valueid"
       + " from %s"
@@ -166,7 +166,7 @@ public Map<OSHDBTag, OSMTag> lookupTag(Set<? extends OSHDBTag> tags) {
     return result;
   }
 
-  private Map<? extends Integer, ? extends String> lookupKeys(Set<? extends Integer> osm) {
+  private Map<Integer, String> lookupKeys(Set<? extends Integer> osm) {
     try (var conn = source.getConnection();
          var sqlArray = createArray(conn, "int", osm);
          var pstmt = conn.prepareStatement(OSHDB_OSM_KEY)) {

oshdb-util/src/test/java/org/heigit/ohsome/oshdb/util/tagtranslator/AbstractTagTranslatorTest.java

@@ -1,7 +1,7 @@
 package org.heigit.ohsome.oshdb.util.tagtranslator;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertSame;
 
 import java.util.ArrayList;
 import java.util.Map;
@@ -128,7 +128,7 @@ void testKeysIdentity() {
       tags.add(instance.lookupTag(new OSHDBTag(1, i)));
     }
     for (var i = 1; i < tags.size(); i++) {
-      assertTrue(tags.get(i - 1).getKey() == tags.get(i).getKey());
+      assertSame(tags.get(i - 1).getKey(), tags.get(i).getKey());
     }
   }
 }