Index: trunk/test/unit/org/openstreetmap/josm/data/osm/DefaultNameFormatterTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/data/osm/DefaultNameFormatterTest.java	(revision 16443)
+++ trunk/test/unit/org/openstreetmap/josm/data/osm/DefaultNameFormatterTest.java	(revision 16445)
@@ -13,4 +13,6 @@
 import java.util.Comparator;
 import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
 
 import org.junit.Rule;
@@ -146,8 +148,6 @@
                 DefaultNameFormatter.getInstance().formatAsHtmlUnorderedList(new Node(1)));
 
-        List<Node> nodes = new ArrayList<>(10);
-        for (int i = 1; i <= 10; i++) {
-            nodes.add(new Node(i, 1));
-        }
+        List<Node> nodes = IntStream.rangeClosed(1, 10).mapToObj(i -> new Node(i, 1))
+                .collect(Collectors.toList());
         assertEquals("<ul><li>1</li><li>2</li><li>3</li><li>4</li><li>...</li></ul>",
                 DefaultNameFormatter.getInstance().formatAsHtmlUnorderedList(nodes, 5));
Index: trunk/test/unit/org/openstreetmap/josm/data/osm/history/HistoryWayTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/data/osm/history/HistoryWayTest.java	(revision 16443)
+++ trunk/test/unit/org/openstreetmap/josm/data/osm/history/HistoryWayTest.java	(revision 16445)
@@ -6,7 +6,7 @@
 import static org.junit.Assert.fail;
 
-import java.util.ArrayList;
 import java.util.Date;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 
@@ -97,8 +97,5 @@
         way.addNode(1);
         way.addNode(2);
-        ArrayList<Long> ids = new ArrayList<>();
-        for (long id : way.getNodes()) {
-            ids.add(id);
-        }
+        List<Long> ids = way.getNodes();
 
         assertEquals(2, ids.size());
Index: trunk/test/unit/org/openstreetmap/josm/data/osm/visitor/MergeSourceBuildingVisitorTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/data/osm/visitor/MergeSourceBuildingVisitorTest.java	(revision 16443)
+++ trunk/test/unit/org/openstreetmap/josm/data/osm/visitor/MergeSourceBuildingVisitorTest.java	(revision 16445)
@@ -31,9 +31,7 @@
         if (primitives == null) return null;
         if (name == null) return null;
-        for (OsmPrimitive primitive: primitives) {
-            if (name.equals(primitive.get("name")))
-                return primitive;
-        }
-        return null;
+        return primitives.stream()
+                .filter(primitive -> name.equals(primitive.get("name")))
+                .findFirst().orElse(null);
     }
 
Index: trunk/test/unit/org/openstreetmap/josm/data/projection/ProjectionRegressionTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/data/projection/ProjectionRegressionTest.java	(revision 16443)
+++ trunk/test/unit/org/openstreetmap/josm/data/projection/ProjectionRegressionTest.java	(revision 16445)
@@ -12,5 +12,4 @@
 import java.security.SecureRandom;
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -59,8 +58,6 @@
         setUp();
 
-        Map<String, Projection> supportedCodesMap = new HashMap<>();
-        for (String code : Projections.getAllProjectionCodes()) {
-            supportedCodesMap.put(code, Projections.getProjectionByCode(code));
-        }
+        Map<String, Projection> supportedCodesMap = Projections.getAllProjectionCodes().stream()
+                .collect(Collectors.toMap(code -> code, Projections::getProjectionByCode));
 
         List<TestData> prevData = new ArrayList<>();
@@ -68,20 +65,11 @@
             prevData = readData();
         }
-        Map<String, TestData> prevCodesMap = new HashMap<>();
-        for (TestData data : prevData) {
-            prevCodesMap.put(data.code, data);
-        }
-
-        Set<String> codesToWrite = new TreeSet<>();
-        for (TestData data : prevData) {
-            if (supportedCodesMap.containsKey(data.code)) {
-                codesToWrite.add(data.code);
-            }
-        }
-        for (String code : supportedCodesMap.keySet()) {
-            if (!codesToWrite.contains(code)) {
-                codesToWrite.add(code);
-            }
-        }
+        Map<String, TestData> prevCodesMap = prevData.stream()
+                .collect(Collectors.toMap(data -> data.code, data -> data));
+
+        Set<String> codesToWrite = new TreeSet<>(supportedCodesMap.keySet());
+        prevData.stream()
+                .filter(data -> supportedCodesMap.containsKey(data.code)).map(data -> data.code)
+                .forEach(codesToWrite::add);
 
         Random rand = new SecureRandom();
Index: trunk/test/unit/org/openstreetmap/josm/data/validation/tests/SelfIntersectingWayTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/data/validation/tests/SelfIntersectingWayTest.java	(revision 16443)
+++ trunk/test/unit/org/openstreetmap/josm/data/validation/tests/SelfIntersectingWayTest.java	(revision 16445)
@@ -4,4 +4,6 @@
 import java.util.ArrayList;
 import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
 
 import org.junit.Assert;
@@ -29,8 +31,5 @@
 
     private static List<Node> createNodes() {
-        List<Node> nodes = new ArrayList<>();
-        for (int i = 0; i < 6; i++) {
-            nodes.add(new Node(i+1));
-        }
+        List<Node> nodes = IntStream.range(0, 6).mapToObj(i -> new Node(i + 1)).collect(Collectors.toList());
         nodes.get(0).setCoor(new LatLon(34.2680, 133.563));
         nodes.get(1).setCoor(new LatLon(34.2509, 133.548));
Index: trunk/test/unit/org/openstreetmap/josm/data/validation/tests/TagCheckerTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/data/validation/tests/TagCheckerTest.java	(revision 16443)
+++ trunk/test/unit/org/openstreetmap/josm/data/validation/tests/TagCheckerTest.java	(revision 16445)
@@ -7,7 +7,7 @@
 
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Consumer;
+import java.util.stream.Collectors;
 
 import org.junit.Assert;
@@ -201,11 +201,9 @@
     @Test
     public void testIgnoredTagsNotInPresets() throws IOException {
-        List<String> errors = new ArrayList<>();
         new TagChecker().initialize();
-        for (Tag tag : TagChecker.getIgnoredTags()) {
-            if (TagChecker.isTagInPresets(tag.getKey(), tag.getValue())) {
-                errors.add(tag.toString());
-            }
-        }
+        List<String> errors = TagChecker.getIgnoredTags().stream()
+                .filter(tag -> TagChecker.isTagInPresets(tag.getKey(), tag.getValue()))
+                .map(Tag::toString)
+                .collect(Collectors.toList());
         assertTrue(errors.toString(), errors.isEmpty());
     }