Improve naming of fields and variables (#10242)

* Variable names to conform to naming convention.

* Use static constants where it makes sense

27 files changed, 151 insertions, 153 deletions

diff --git a/server/src/main/java/com/vaadin/data/BeanPropertySet.java b/server/src/main/java/com/vaadin/data/BeanPropertySet.java
index ae14c31d83..dcbff134d4 100644
--- a/server/src/main/java/com/vaadin/data/BeanPropertySet.java
+++ b/server/src/main/java/com/vaadin/data/BeanPropertySet.java
@@ -270,7 +270,7 @@ public class BeanPropertySet<T> implements PropertySet<T> {
         }
     }
 
-    private static final ConcurrentMap<Class<?>, BeanPropertySet<?>> instances = new ConcurrentHashMap<>();
+    private static final ConcurrentMap<Class<?>, BeanPropertySet<?>> INSTANCES = new ConcurrentHashMap<>();
 
     private final Class<T> beanType;
 
@@ -306,7 +306,7 @@ public class BeanPropertySet<T> implements PropertySet<T> {
         Objects.requireNonNull(beanType, "Bean type cannot be null");
 
         // Cache the reflection results
-        return (PropertySet<T>) instances.computeIfAbsent(beanType,
+        return (PropertySet<T>) INSTANCES.computeIfAbsent(beanType,
                 BeanPropertySet::new);
     }
 
diff --git a/server/src/main/java/com/vaadin/event/dd/acceptcriteria/AcceptAll.java b/server/src/main/java/com/vaadin/event/dd/acceptcriteria/AcceptAll.java
index 6dfca521a4..d7684b0142 100644
--- a/server/src/main/java/com/vaadin/event/dd/acceptcriteria/AcceptAll.java
+++ b/server/src/main/java/com/vaadin/event/dd/acceptcriteria/AcceptAll.java
@@ -29,13 +29,13 @@ import com.vaadin.event.dd.DragAndDropEvent;
 public final class AcceptAll extends ClientSideCriterion {
 
     private static final long serialVersionUID = 7406683402153141461L;
-    private static final AcceptCriterion singleton = new AcceptAll();
+    private static final AcceptCriterion SINGLETON = new AcceptAll();
 
     private AcceptAll() {
     }
 
     public static AcceptCriterion get() {
-        return singleton;
+        return SINGLETON;
     }
 
     @Override
diff --git a/server/src/main/java/com/vaadin/event/dd/acceptcriteria/SourceIsTarget.java b/server/src/main/java/com/vaadin/event/dd/acceptcriteria/SourceIsTarget.java
index 8c4b82c0c7..292ac636a7 100644
--- a/server/src/main/java/com/vaadin/event/dd/acceptcriteria/SourceIsTarget.java
+++ b/server/src/main/java/com/vaadin/event/dd/acceptcriteria/SourceIsTarget.java
@@ -35,7 +35,7 @@ import com.vaadin.ui.Component;
 public class SourceIsTarget extends ClientSideCriterion {
 
     private static final long serialVersionUID = -451399314705532584L;
-    private static final SourceIsTarget instance = new SourceIsTarget();
+    private static final SourceIsTarget INSTANCE = new SourceIsTarget();
 
     private SourceIsTarget() {
     }
@@ -52,7 +52,7 @@ public class SourceIsTarget extends ClientSideCriterion {
     }
 
     public static synchronized SourceIsTarget get() {
-        return instance;
+        return INSTANCE;
     }
 
 }
diff --git a/server/src/main/java/com/vaadin/server/AbstractClientConnector.java b/server/src/main/java/com/vaadin/server/AbstractClientConnector.java
index 9086bf2cc2..d194dce51c 100644
--- a/server/src/main/java/com/vaadin/server/AbstractClientConnector.java
+++ b/server/src/main/java/com/vaadin/server/AbstractClientConnector.java
@@ -99,7 +99,7 @@ public abstract class AbstractClientConnector
      * ShareState classes. Using WeakHashMap since entries are recalculated on
      * demand.
      */
-    private static final Map<Class<? extends AbstractClientConnector>, Class<? extends SharedState>> stateTypeCache = Collections
+    private static final Map<Class<? extends AbstractClientConnector>, Class<? extends SharedState>> STATE_TYPE_CACHE = Collections
             .synchronizedMap(new WeakHashMap<>());
 
     @Override
@@ -315,7 +315,7 @@ public abstract class AbstractClientConnector
         // exceptions flying around
         if (stateType == null) {
             // Cache because we don't need to do this once per instance
-            stateType = stateTypeCache.computeIfAbsent(this.getClass(),
+            stateType = STATE_TYPE_CACHE.computeIfAbsent(this.getClass(),
                     key -> findStateType());
         }
 
diff --git a/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java b/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
index 8fe7892c39..58761f1e10 100644
--- a/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
+++ b/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
@@ -371,13 +371,13 @@ public class ComponentSizeValidator implements Serializable {
     private static void showComponent(Component component, String attribute,
             StringBuilder err, StringBuilder indent, boolean widthError) {
 
-        FileLocation createLoc = creationLocations.get(component);
+        FileLocation createLoc = CREATION_LOCATIONS.get(component);
 
         FileLocation sizeLoc;
         if (widthError) {
-            sizeLoc = widthLocations.get(component);
+            sizeLoc = WIDTH_LOCATIONS.get(component);
         } else {
-            sizeLoc = heightLocations.get(component);
+            sizeLoc = HEIGHT_LOCATIONS.get(component);
         }
 
         err.append(indent);
@@ -600,9 +600,9 @@ public class ComponentSizeValidator implements Serializable {
 
     }
 
-    private static final Map<Object, FileLocation> creationLocations = new HashMap<>();
-    private static final Map<Object, FileLocation> widthLocations = new HashMap<>();
-    private static final Map<Object, FileLocation> heightLocations = new HashMap<>();
+    private static final Map<Object, FileLocation> CREATION_LOCATIONS = new HashMap<>();
+    private static final Map<Object, FileLocation> WIDTH_LOCATIONS = new HashMap<>();
+    private static final Map<Object, FileLocation> HEIGHT_LOCATIONS = new HashMap<>();
 
     public static class FileLocation implements Serializable {
         public String method;
@@ -622,15 +622,15 @@ public class ComponentSizeValidator implements Serializable {
     }
 
     public static void setCreationLocation(Object object) {
-        setLocation(creationLocations, object);
+        setLocation(CREATION_LOCATIONS, object);
     }
 
     public static void setWidthLocation(Object object) {
-        setLocation(widthLocations, object);
+        setLocation(WIDTH_LOCATIONS, object);
     }
 
     public static void setHeightLocation(Object object) {
-        setLocation(heightLocations, object);
+        setLocation(HEIGHT_LOCATIONS, object);
     }
 
     private static void setLocation(Map<Object, FileLocation> map,
diff --git a/server/src/main/java/com/vaadin/server/DefaultSystemMessagesProvider.java b/server/src/main/java/com/vaadin/server/DefaultSystemMessagesProvider.java
index 971587d74b..3acb1191f5 100644
--- a/server/src/main/java/com/vaadin/server/DefaultSystemMessagesProvider.java
+++ b/server/src/main/java/com/vaadin/server/DefaultSystemMessagesProvider.java
@@ -25,7 +25,7 @@ package com.vaadin.server;
  */
 public class DefaultSystemMessagesProvider implements SystemMessagesProvider {
 
-    private static final DefaultSystemMessagesProvider instance = new DefaultSystemMessagesProvider();
+    private static final DefaultSystemMessagesProvider INSTANCE = new DefaultSystemMessagesProvider();
 
     private DefaultSystemMessagesProvider() {
         // Singleton
@@ -43,7 +43,7 @@ public class DefaultSystemMessagesProvider implements SystemMessagesProvider {
      * @return the default system messages provider.
      */
     public static SystemMessagesProvider get() {
-        return instance;
+        return INSTANCE;
     }
 
 }
diff --git a/server/src/main/java/com/vaadin/server/GlobalResourceHandler.java b/server/src/main/java/com/vaadin/server/GlobalResourceHandler.java
index 11e6832696..d8f312d4ea 100644
--- a/server/src/main/java/com/vaadin/server/GlobalResourceHandler.java
+++ b/server/src/main/java/com/vaadin/server/GlobalResourceHandler.java
@@ -60,7 +60,7 @@ public class GlobalResourceHandler implements RequestHandler {
     private int nextLegacyId = 0;
 
     // APP/global/[uiid]/[type]/[id]
-    private static final Pattern pattern = Pattern
+    private static final Pattern PATTERN = Pattern
             .compile("^/?" + ApplicationConstants.APP_PATH + '/'
                     + RESOURCE_REQUEST_PATH + "(\\d+)/(([^/]+)(/.*))");
 
@@ -72,7 +72,7 @@ public class GlobalResourceHandler implements RequestHandler {
             return false;
         }
 
-        Matcher matcher = pattern.matcher(pathInfo);
+        Matcher matcher = PATTERN.matcher(pathInfo);
         if (!matcher.matches()) {
             return false;
         }
diff --git a/server/src/main/java/com/vaadin/server/JsonCodec.java b/server/src/main/java/com/vaadin/server/JsonCodec.java
index fc8e858b3b..5f26d14513 100644
--- a/server/src/main/java/com/vaadin/server/JsonCodec.java
+++ b/server/src/main/java/com/vaadin/server/JsonCodec.java
@@ -206,19 +206,19 @@ public class JsonCodec implements Serializable {
      * happens to process Vaadin requests, so it must be protected from
      * corruption caused by concurrent access.
      */
-    private static final ConcurrentMap<Class<?>, Collection<BeanProperty>> typePropertyCache = new ConcurrentHashMap<>();
+    private static final ConcurrentMap<Class<?>, Collection<BeanProperty>> TYPE_PROPERTY_CACHE = new ConcurrentHashMap<>();
 
-    private static final Map<Class<?>, String> typeToTransportType = new HashMap<>();
+    private static final Map<Class<?>, String> TYPE_TO_TRANSPORT_TYPE = new HashMap<>();
 
     /**
      * Note! This does not contain primitives.
      * <p>
      */
-    private static final Map<String, Class<?>> transportTypeToType = new HashMap<>();
+    private static final Map<String, Class<?>> TRANSPORT_TYPE_TO_TYPE = new HashMap<>();
 
-    private static final Map<Class<?>, JSONSerializer<?>> customSerializers = new HashMap<>();
+    private static final Map<Class<?>, JSONSerializer<?>> CUSTOM_SERIALIZERS = new HashMap<>();
     static {
-        customSerializers.put(Date.class, new DateSerializer());
+        CUSTOM_SERIALIZERS.put(Date.class, new DateSerializer());
     }
 
     static {
@@ -244,14 +244,14 @@ public class JsonCodec implements Serializable {
     }
 
     private static void registerType(Class<?> type, String transportType) {
-        typeToTransportType.put(type, transportType);
+        TYPE_TO_TRANSPORT_TYPE.put(type, transportType);
         if (!type.isPrimitive()) {
-            transportTypeToType.put(transportType, type);
+            TRANSPORT_TYPE_TO_TYPE.put(transportType, type);
         }
     }
 
     public static boolean isInternalTransportType(String transportType) {
-        return transportTypeToType.containsKey(transportType);
+        return TRANSPORT_TYPE_TO_TYPE.containsKey(transportType);
     }
 
     public static boolean isInternalType(Type type) {
@@ -267,7 +267,7 @@ public class JsonCodec implements Serializable {
             // value
             return true;
         }
-        return typeToTransportType.containsKey(getClassForType(type));
+        return TYPE_TO_TRANSPORT_TYPE.containsKey(getClassForType(type));
     }
 
     private static Class<?> getClassForType(Type type) {
@@ -281,7 +281,7 @@ public class JsonCodec implements Serializable {
     }
 
     private static Class<?> getType(String transportType) {
-        return transportTypeToType.get(transportType);
+        return TRANSPORT_TYPE_TO_TYPE.get(transportType);
     }
 
     public static Object decodeInternalOrCustomType(Type targetType,
@@ -329,8 +329,8 @@ public class JsonCodec implements Serializable {
             Class<?> classForType = getClassForType(targetType);
             return decodeEnum(classForType.asSubclass(Enum.class),
                     (JsonString) value);
-        } else if (customSerializers.containsKey(getClassForType(targetType))) {
-            return customSerializers.get(getClassForType(targetType))
+        } else if (CUSTOM_SERIALIZERS.containsKey(getClassForType(targetType))) {
+            return CUSTOM_SERIALIZERS.get(getClassForType(targetType))
                     .deserialize(targetType, value, connectorTracker);
         } else {
             return decodeObject(targetType, (JsonObject) value,
@@ -669,7 +669,7 @@ public class JsonCodec implements Serializable {
             toReturn = Json.create(((Connector) value).getConnectorId());
         } else if (value instanceof Enum) {
             toReturn = Json.create(((Enum<?>) value).name());
-        } else if (customSerializers.containsKey(value.getClass())) {
+        } else if (CUSTOM_SERIALIZERS.containsKey(value.getClass())) {
             toReturn = serializeJson(value, connectorTracker);
         } else if (valueType instanceof GenericArrayType) {
             toReturn = encodeArrayContents(
@@ -695,7 +695,7 @@ public class JsonCodec implements Serializable {
 
     public static Collection<BeanProperty> getProperties(Class<?> type)
             throws IntrospectionException {
-        Collection<BeanProperty> cachedProperties = typePropertyCache.get(type);
+        Collection<BeanProperty> cachedProperties = TYPE_PROPERTY_CACHE.get(type);
         if (cachedProperties != null) {
             return cachedProperties;
         }
@@ -706,7 +706,7 @@ public class JsonCodec implements Serializable {
 
         // Doesn't matter if the same calculation is done multiple times from
         // different threads, so there's no need to do e.g. putIfAbsent
-        typePropertyCache.put(type, properties);
+        TYPE_PROPERTY_CACHE.put(type, properties);
         return properties;
     }
 
@@ -982,12 +982,12 @@ public class JsonCodec implements Serializable {
      * of the hot part.
      */
     private static String getInternalTransportType(Type valueType) {
-        return typeToTransportType.get(getClassForType(valueType));
+        return TYPE_TO_TRANSPORT_TYPE.get(getClassForType(valueType));
     }
 
     private static JsonValue serializeJson(Object value,
             ConnectorTracker connectorTracker) {
-        JSONSerializer serializer = customSerializers.get(value.getClass());
+        JSONSerializer serializer = CUSTOM_SERIALIZERS.get(value.getClass());
         return serializer.serialize(value, connectorTracker);
     }
 
diff --git a/server/src/main/java/com/vaadin/server/LegacyCommunicationManager.java b/server/src/main/java/com/vaadin/server/LegacyCommunicationManager.java
index cebb90a0ad..c66609b17b 100644
--- a/server/src/main/java/com/vaadin/server/LegacyCommunicationManager.java
+++ b/server/src/main/java/com/vaadin/server/LegacyCommunicationManager.java
@@ -82,7 +82,7 @@ public class LegacyCommunicationManager implements Serializable {
         return session;
     }
 
-    private static final ConcurrentHashMap<Class<? extends SharedState>, JsonValue> referenceDiffStates = new ConcurrentHashMap<>();
+    private static final ConcurrentHashMap<Class<? extends SharedState>, JsonValue> REFERENCE_DIFF_STATES = new ConcurrentHashMap<>();
 
     /**
      * @deprecated As of 7.1. See #11411.
@@ -98,10 +98,10 @@ public class LegacyCommunicationManager implements Serializable {
         if (diffState == null) {
             // Use an empty state object as reference for full
             // repaints
-            diffState = referenceDiffStates.get(stateType);
+            diffState = REFERENCE_DIFF_STATES.get(stateType);
             if (diffState == null) {
                 diffState = createReferenceDiffStateState(stateType);
-                referenceDiffStates.put(stateType, diffState);
+                REFERENCE_DIFF_STATES.put(stateType, diffState);
             }
         }
         EncodeResult encodeResult = JsonCodec.encode(state, diffState,
diff --git a/server/src/main/java/com/vaadin/server/LegacyVaadinPortlet.java b/server/src/main/java/com/vaadin/server/LegacyVaadinPortlet.java
index 831239096a..56a1d7b806 100644
--- a/server/src/main/java/com/vaadin/server/LegacyVaadinPortlet.java
+++ b/server/src/main/java/com/vaadin/server/LegacyVaadinPortlet.java
@@ -24,7 +24,7 @@ import com.vaadin.util.ReflectTools;
 
 public class LegacyVaadinPortlet extends VaadinPortlet {
 
-    private static final LegacyApplicationUIProvider provider = new LegacyApplicationUIProvider() {
+    private static final LegacyApplicationUIProvider PROVIDER = new LegacyApplicationUIProvider() {
         @Override
         protected LegacyApplication createApplication() {
             VaadinPortlet portlet = VaadinPortlet.getCurrent();
@@ -80,7 +80,7 @@ public class LegacyVaadinPortlet extends VaadinPortlet {
 
     private void onVaadinSessionStarted(VaadinPortletRequest request,
             VaadinPortletSession session) throws PortletException {
-        session.addUIProvider(provider);
+        session.addUIProvider(PROVIDER);
     }
 
     protected boolean shouldCreateApplication(PortletRequest request) {
diff --git a/server/src/main/java/com/vaadin/server/LegacyVaadinServlet.java b/server/src/main/java/com/vaadin/server/LegacyVaadinServlet.java
index 70174fdc32..b5da2da2a4 100644
--- a/server/src/main/java/com/vaadin/server/LegacyVaadinServlet.java
+++ b/server/src/main/java/com/vaadin/server/LegacyVaadinServlet.java
@@ -24,7 +24,7 @@ import com.vaadin.util.ReflectTools;
 
 public class LegacyVaadinServlet extends VaadinServlet {
 
-    private static final UIProvider provider = new LegacyApplicationUIProvider() {
+    private static final UIProvider PROVIDER = new LegacyApplicationUIProvider() {
         @Override
         protected LegacyApplication createApplication() {
 
@@ -84,7 +84,7 @@ public class LegacyVaadinServlet extends VaadinServlet {
 
     private void onVaadinSessionStarted(VaadinRequest request,
             VaadinSession session) throws ServletException {
-        session.addUIProvider(provider);
+        session.addUIProvider(PROVIDER);
     }
 
 }
diff --git a/server/src/main/java/com/vaadin/server/LocaleService.java b/server/src/main/java/com/vaadin/server/LocaleService.java
index 9ec7e1282f..dac57a1bd7 100644
--- a/server/src/main/java/com/vaadin/server/LocaleService.java
+++ b/server/src/main/java/com/vaadin/server/LocaleService.java
@@ -177,15 +177,15 @@ public class LocaleService implements Serializable {
 
         localeData.dateFormat = datePattern.trim();
 
-        final boolean twelve_hour_clock = timePattern.indexOf("a") > -1;
+        final boolean twelveHourClock = timePattern.indexOf("a") > -1;
         // TODO there are other possibilities as well, like 'h' in french
         // (ignore them, too complicated)
-        final String hour_min_delimiter = timePattern.indexOf(".") > -1 ? "."
+        final String hourMinDelimiter = timePattern.indexOf(".") > -1 ? "."
                 : ":";
 
-        localeData.twelveHourClock = twelve_hour_clock;
-        localeData.hourMinuteDelimiter = hour_min_delimiter;
-        if (twelve_hour_clock) {
+        localeData.twelveHourClock = twelveHourClock;
+        localeData.hourMinuteDelimiter = hourMinDelimiter;
+        if (twelveHourClock) {
             final String[] ampm = dfs.getAmPmStrings();
             localeData.am = ampm[0];
             localeData.pm = ampm[1];
diff --git a/server/src/main/java/com/vaadin/server/ServerRpcManager.java b/server/src/main/java/com/vaadin/server/ServerRpcManager.java
index 30c8ec48ba..ba6d0b6ee5 100644
--- a/server/src/main/java/com/vaadin/server/ServerRpcManager.java
+++ b/server/src/main/java/com/vaadin/server/ServerRpcManager.java
@@ -68,7 +68,7 @@ public class ServerRpcManager<T extends ServerRpc> implements Serializable {
 
     }
 
-    private static final Map<Class<?>, Class<?>> boxedTypes = new HashMap<>();
+    private static final Map<Class<?>, Class<?>> BOXED_TYPES = new HashMap<>();
     static {
         try {
             Class<?>[] boxClasses = new Class<?>[] { Boolean.class, Byte.class,
@@ -77,7 +77,7 @@ public class ServerRpcManager<T extends ServerRpc> implements Serializable {
             for (Class<?> boxClass : boxClasses) {
                 Field typeField = boxClass.getField("TYPE");
                 Class<?> primitiveType = (Class<?>) typeField.get(boxClass);
-                boxedTypes.put(primitiveType, boxClass);
+                BOXED_TYPES.put(primitiveType, boxClass);
             }
         } catch (Exception e) {
             throw new RuntimeException(e);
diff --git a/server/src/main/java/com/vaadin/server/ServerRpcMethodInvocation.java b/server/src/main/java/com/vaadin/server/ServerRpcMethodInvocation.java
index f4e2b4064d..98b436f489 100644
--- a/server/src/main/java/com/vaadin/server/ServerRpcMethodInvocation.java
+++ b/server/src/main/java/com/vaadin/server/ServerRpcMethodInvocation.java
@@ -24,7 +24,7 @@ import com.vaadin.shared.communication.ServerRpc;
 
 public class ServerRpcMethodInvocation extends MethodInvocation {
 
-    private static final Map<String, Method> invocationMethodCache = new ConcurrentHashMap<>(
+    private static final Map<String, Method> INVOCATION_METHOD_CACHE = new ConcurrentHashMap<>(
             128, 0.75f, 1);
 
     private final Method method;
@@ -67,14 +67,14 @@ public class ServerRpcMethodInvocation extends MethodInvocation {
         // signature
         String signature = targetType.getName() + "." + methodName + "("
                 + parameterCount;
-        Method invocationMethod = invocationMethodCache.get(signature);
+        Method invocationMethod = INVOCATION_METHOD_CACHE.get(signature);
 
         if (invocationMethod == null) {
             invocationMethod = doFindInvocationMethod(targetType, methodName,
                     parameterCount);
 
             if (invocationMethod != null) {
-                invocationMethodCache.put(signature, invocationMethod);
+                INVOCATION_METHOD_CACHE.put(signature, invocationMethod);
             }
         }
 
diff --git a/server/src/main/java/com/vaadin/server/SizeWithUnit.java b/server/src/main/java/com/vaadin/server/SizeWithUnit.java
index 935f7dd050..57765164e1 100644
--- a/server/src/main/java/com/vaadin/server/SizeWithUnit.java
+++ b/server/src/main/java/com/vaadin/server/SizeWithUnit.java
@@ -32,7 +32,7 @@ import com.vaadin.shared.util.SharedUtil;
 public class SizeWithUnit implements Serializable {
     private final float size;
     private final Unit unit;
-    private static final Pattern sizePattern = Pattern
+    private static final Pattern SIZE_PATTERN = Pattern
             .compile(SharedUtil.SIZE_PATTERN);
 
     /**
@@ -90,7 +90,7 @@ public class SizeWithUnit implements Serializable {
         }
         float size = 0;
         Unit unit = null;
-        Matcher matcher = sizePattern.matcher(s);
+        Matcher matcher = SIZE_PATTERN.matcher(s);
         if (matcher.find()) {
             size = Float.parseFloat(matcher.group(1));
             if (size < 0) {
@@ -107,7 +107,7 @@ public class SizeWithUnit implements Serializable {
             }
         } else {
             throw new IllegalArgumentException("Invalid size argument: \"" + s
-                    + "\" (should match " + sizePattern.pattern() + ")");
+                    + "\" (should match " + SIZE_PATTERN.pattern() + ")");
         }
         return new SizeWithUnit(size, unit);
     }
diff --git a/server/src/main/java/com/vaadin/server/StreamResource.java b/server/src/main/java/com/vaadin/server/StreamResource.java
index 6b8f36ba54..9b6e02d0f6 100644
--- a/server/src/main/java/com/vaadin/server/StreamResource.java
+++ b/server/src/main/java/com/vaadin/server/StreamResource.java
@@ -41,7 +41,7 @@ public class StreamResource implements ConnectorResource {
     /**
      * Explicit mime-type.
      */
-    private String MIMEType = null;
+    private String mimeType = null;
 
     /**
      * Filename.
@@ -76,8 +76,8 @@ public class StreamResource implements ConnectorResource {
      */
     @Override
     public String getMIMEType() {
-        if (MIMEType != null) {
-            return MIMEType;
+        if (mimeType != null) {
+            return mimeType;
         }
         return FileTypeResolver.getMIMEType(filename);
     }
@@ -85,11 +85,11 @@ public class StreamResource implements ConnectorResource {
     /**
      * Sets the mime type of the resource.
      *
-     * @param MIMEType
+     * @param mimeType
      *            the MIME type to be set.
      */
-    public void setMIMEType(String MIMEType) {
-        this.MIMEType = MIMEType;
+    public void setMIMEType(String mimeType) {
+        this.mimeType = mimeType;
     }
 
     /**
@@ -223,7 +223,7 @@ public class StreamResource implements ConnectorResource {
         } else if (obj instanceof StreamResource) {
             StreamResource that = (StreamResource) obj;
             return SharedUtil.equals(getStreamSource(), that.getStreamSource())
-                    && SharedUtil.equals(MIMEType, that.MIMEType)
+                    && SharedUtil.equals(mimeType, that.mimeType)
                     && SharedUtil.equals(getFilename(), that.getFilename())
                     && getBufferSize() == that.getBufferSize()
                     && getCacheTime() == that.getCacheTime();
@@ -234,7 +234,7 @@ public class StreamResource implements ConnectorResource {
 
     @Override
     public int hashCode() {
-        return Arrays.hashCode(new Object[] { getStreamSource(), MIMEType,
+        return Arrays.hashCode(new Object[] { getStreamSource(), mimeType,
                 getFilename(), getBufferSize(), getCacheTime() });
     }
 
diff --git a/server/src/main/java/com/vaadin/server/widgetsetutils/ClassPathExplorer.java b/server/src/main/java/com/vaadin/server/widgetsetutils/ClassPathExplorer.java
index 74f8e1d013..31053fa778 100644
--- a/server/src/main/java/com/vaadin/server/widgetsetutils/ClassPathExplorer.java
+++ b/server/src/main/java/com/vaadin/server/widgetsetutils/ClassPathExplorer.java
@@ -92,15 +92,15 @@ public class ClassPathExplorer {
      * entries that could include widgets/widgetsets are listed (primarily
      * directories, Vaadin JARs and add-on JARs).
      */
-    private static final List<String> rawClasspathEntries = getRawClasspathEntries();
+    private static final List<String> RAW_CLASSPATH_ENTRIES = getRawClasspathEntries();
 
     /**
      * Map from identifiers (either a package name preceded by the path and a
      * slash, or a URL for a JAR file) to the corresponding URLs. This is
      * constructed from the class path.
      */
-    private static final Map<String, URL> classpathLocations = getClasspathLocations(
-            rawClasspathEntries);
+    private static final Map<String, URL> CLASSPATH_LOCATIONS = getClasspathLocations(
+            RAW_CLASSPATH_ENTRIES);
 
     private static boolean debug = false;
 
@@ -138,7 +138,7 @@ public class ClassPathExplorer {
         long start = System.currentTimeMillis();
         Map<String, URL> widgetsets = new HashMap<>();
         Map<String, URL> themes = new HashMap<>();
-        Set<String> keySet = classpathLocations.keySet();
+        Set<String> keySet = CLASSPATH_LOCATIONS.keySet();
         for (String location : keySet) {
             searchForWidgetSetsAndAddonStyles(location, widgetsets, themes);
         }
@@ -179,16 +179,16 @@ public class ClassPathExplorer {
      * "Vaadin-Widgetsets" attribute in its manifest are added to widgetsets.
      *
      * @param locationString
-     *            an entry in {@link #classpathLocations}
+     *            an entry in {@link #CLASSPATH_LOCATIONS}
      * @param widgetsets
      *            a map from widgetset name (including package, with dots as
-     *            separators) to a URL (see {@link #classpathLocations}) - new
+     *            separators) to a URL (see {@link #CLASSPATH_LOCATIONS}) - new
      *            entries are added to this map
      */
     private static void searchForWidgetSetsAndAddonStyles(String locationString,
             Map<String, URL> widgetsets, Map<String, URL> addonStyles) {
 
-        URL location = classpathLocations.get(locationString);
+        URL location = CLASSPATH_LOCATIONS.get(locationString);
         File directory = new File(location.getFile());
 
         if (directory.exists() && !directory.isHidden()) {
@@ -329,12 +329,12 @@ public class ClassPathExplorer {
      * Determine every URL location defined by the current classpath, and it's
      * associated package name.
      *
-     * See {@link #classpathLocations} for information on output format.
+     * See {@link #CLASSPATH_LOCATIONS} for information on output format.
      *
      * @param rawClasspathEntries
      *            raw class path entries as split from the Java class path
      *            string
-     * @return map of classpath locations, see {@link #classpathLocations}
+     * @return map of classpath locations, see {@link #CLASSPATH_LOCATIONS}
      */
     private static final Map<String, URL> getClasspathLocations(
             List<String> rawClasspathEntries) {
@@ -419,7 +419,7 @@ public class ClassPathExplorer {
 
     /**
      * Recursively add subdirectories and jar files to locations - see
-     * {@link #classpathLocations}.
+     * {@link #CLASSPATH_LOCATIONS}.
      *
      * @param name
      * @param file
@@ -465,7 +465,7 @@ public class ClassPathExplorer {
     }
 
     /**
-     * Add a jar file to locations - see {@link #classpathLocations}.
+     * Add a jar file to locations - see {@link #CLASSPATH_LOCATIONS}.
      *
      * @param file
      * @param locations
@@ -522,14 +522,14 @@ public class ClassPathExplorer {
         if (debug) {
             debug("classpathLocations values:");
             List<String> locations = new ArrayList<>(
-                    classpathLocations.keySet());
+                    CLASSPATH_LOCATIONS.keySet());
             for (String location : locations) {
-                debug(String.valueOf(classpathLocations.get(location)));
+                debug(String.valueOf(CLASSPATH_LOCATIONS.get(location)));
             }
         }
 
         URL firstDirectory = null;
-        for (String entry : rawClasspathEntries) {
+        for (String entry : RAW_CLASSPATH_ENTRIES) {
 
             File directory = new File(entry);
             if (directory.exists() && !directory.isHidden()
diff --git a/server/src/main/java/com/vaadin/ui/AbstractComponent.java b/server/src/main/java/com/vaadin/ui/AbstractComponent.java
index 7a87230125..89dd61986a 100644
--- a/server/src/main/java/com/vaadin/ui/AbstractComponent.java
+++ b/server/src/main/java/com/vaadin/ui/AbstractComponent.java
@@ -1251,7 +1251,7 @@ public abstract class AbstractComponent extends AbstractClientConnector
      *         implementation
      */
     protected Collection<String> getCustomAttributes() {
-        List<String> l = new ArrayList<>(Arrays.asList(customAttributes));
+        List<String> l = new ArrayList<>(Arrays.asList(CUSTOM_ATTRIBUTES));
         if (this instanceof Focusable) {
             l.add("tab-index");
             l.add("tabindex");
@@ -1259,7 +1259,7 @@ public abstract class AbstractComponent extends AbstractClientConnector
         return l;
     }
 
-    private static final String[] customAttributes = { "width", "height",
+    private static final String[] CUSTOM_ATTRIBUTES = { "width", "height",
             "debug-id", "error", "width-auto", "height-auto", "width-full",
             "height-full", "size-auto", "size-full", "immediate", "locale",
             "read-only", "_id" };
diff --git a/server/src/main/java/com/vaadin/ui/Upload.java b/server/src/main/java/com/vaadin/ui/Upload.java
index 9096d8bc40..b8ae510059 100644
--- a/server/src/main/java/com/vaadin/ui/Upload.java
+++ b/server/src/main/java/com/vaadin/ui/Upload.java
@@ -280,15 +280,15 @@ public class Upload extends AbstractComponent
          *            the source of the file.
          * @param filename
          *            the received file name.
-         * @param MIMEType
+         * @param mimeType
          *            the MIME type of the received file.
          * @param length
          *            the length of the received file.
          */
-        public FinishedEvent(Upload source, String filename, String MIMEType,
+        public FinishedEvent(Upload source, String filename, String mimeType,
                 long length) {
             super(source);
-            type = MIMEType;
+            type = mimeType;
             this.filename = filename;
             this.length = length;
         }
@@ -346,13 +346,13 @@ public class Upload extends AbstractComponent
          *
          * @param source
          * @param filename
-         * @param MIMEType
+         * @param mimeType
          * @param length
          * @param reason
          */
-        public FailedEvent(Upload source, String filename, String MIMEType,
+        public FailedEvent(Upload source, String filename, String mimeType,
                 long length, Exception reason) {
-            this(source, filename, MIMEType, length);
+            this(source, filename, mimeType, length);
             this.reason = reason;
         }
 
@@ -360,12 +360,12 @@ public class Upload extends AbstractComponent
          *
          * @param source
          * @param filename
-         * @param MIMEType
+         * @param mimeType
          * @param length
          */
-        public FailedEvent(Upload source, String filename, String MIMEType,
+        public FailedEvent(Upload source, String filename, String mimeType,
                 long length) {
-            super(source, filename, MIMEType, length);
+            super(source, filename, mimeType, length);
         }
 
         /**
@@ -388,12 +388,12 @@ public class Upload extends AbstractComponent
          *
          * @param source
          * @param filename
-         * @param MIMEType
+         * @param mimeType
          * @param length
          */
         public NoOutputStreamEvent(Upload source, String filename,
-                String MIMEType, long length) {
-            super(source, filename, MIMEType, length);
+                String mimeType, long length) {
+            super(source, filename, mimeType, length);
         }
     }
 
@@ -406,14 +406,13 @@ public class Upload extends AbstractComponent
          *
          * @param source
          * @param filename
-         * @param MIMEType
+         * @param mimeType
          * @param length
          */
         public NoInputStreamEvent(Upload source, String filename,
-                String MIMEType, long length) {
-            super(source, filename, MIMEType, length);
+                String mimeType, long length) {
+            super(source, filename, mimeType, length);
         }
-
     }
 
     /**
@@ -429,14 +428,13 @@ public class Upload extends AbstractComponent
          *
          * @param source
          * @param filename
-         * @param MIMEType
+         * @param mimeType
          * @param length
          */
-        public SucceededEvent(Upload source, String filename, String MIMEType,
+        public SucceededEvent(Upload source, String filename, String mimeType,
                 long length) {
-            super(source, filename, MIMEType, length);
+            super(source, filename, mimeType, length);
         }
-
     }
 
     /**
@@ -458,14 +456,14 @@ public class Upload extends AbstractComponent
          *
          * @param source
          * @param filename
-         * @param MIMEType
+         * @param mimeType
          * @param contentLength
          */
-        public StartedEvent(Upload source, String filename, String MIMEType,
+        public StartedEvent(Upload source, String filename, String mimeType,
                 long contentLength) {
             super(source);
             this.filename = filename;
-            type = MIMEType;
+            type = mimeType;
             length = contentLength;
         }
 
@@ -783,10 +781,10 @@ public class Upload extends AbstractComponent
      * Emit upload received event.
      *
      * @param filename
-     * @param MIMEType
+     * @param mimeType
      */
-    protected void fireStarted(String filename, String MIMEType) {
-        fireEvent(new Upload.StartedEvent(this, filename, MIMEType,
+    protected void fireStarted(String filename, String mimeType) {
+        fireEvent(new Upload.StartedEvent(this, filename, mimeType,
                 contentLength));
     }
 
@@ -794,29 +792,29 @@ public class Upload extends AbstractComponent
      * Emits the upload failed event.
      *
      * @param filename
-     * @param MIMEType
+     * @param mimeType
      * @param length
      */
-    protected void fireUploadInterrupted(String filename, String MIMEType,
+    protected void fireUploadInterrupted(String filename, String mimeType,
             long length) {
-        fireEvent(new Upload.FailedEvent(this, filename, MIMEType, length));
+        fireEvent(new Upload.FailedEvent(this, filename, mimeType, length));
     }
 
-    protected void fireNoInputStream(String filename, String MIMEType,
+    protected void fireNoInputStream(String filename, String mimeType,
             long length) {
-        fireEvent(new Upload.NoInputStreamEvent(this, filename, MIMEType,
+        fireEvent(new Upload.NoInputStreamEvent(this, filename, mimeType,
                 length));
     }
 
-    protected void fireNoOutputStream(String filename, String MIMEType,
+    protected void fireNoOutputStream(String filename, String mimeType,
             long length) {
-        fireEvent(new Upload.NoOutputStreamEvent(this, filename, MIMEType,
+        fireEvent(new Upload.NoOutputStreamEvent(this, filename, mimeType,
                 length));
     }
 
-    protected void fireUploadInterrupted(String filename, String MIMEType,
+    protected void fireUploadInterrupted(String filename, String mimeType,
             long length, Exception e) {
-        fireEvent(new Upload.FailedEvent(this, filename, MIMEType, length, e));
+        fireEvent(new Upload.FailedEvent(this, filename, mimeType, length, e));
     }
 
     /**
diff --git a/server/src/main/java/com/vaadin/ui/declarative/DesignAttributeHandler.java b/server/src/main/java/com/vaadin/ui/declarative/DesignAttributeHandler.java
index c508b693f8..4115edfde0 100644
--- a/server/src/main/java/com/vaadin/ui/declarative/DesignAttributeHandler.java
+++ b/server/src/main/java/com/vaadin/ui/declarative/DesignAttributeHandler.java
@@ -59,7 +59,7 @@ public class DesignAttributeHandler implements Serializable {
         return Logger.getLogger(DesignAttributeHandler.class.getName());
     }
 
-    private static final Map<Class<?>, AttributeCacheEntry> cache = new ConcurrentHashMap<>();
+    private static final Map<Class<?>, AttributeCacheEntry> CACHE = new ConcurrentHashMap<>();
 
     // translates string <-> object
     private static final DesignFormatter FORMATTER = new DesignFormatter();
@@ -145,7 +145,7 @@ public class DesignAttributeHandler implements Serializable {
      */
     public static Collection<String> getSupportedAttributes(Class<?> clazz) {
         resolveSupportedAttributes(clazz);
-        return cache.get(clazz).getAttributes();
+        return CACHE.get(clazz).getAttributes();
     }
 
     /**
@@ -160,7 +160,7 @@ public class DesignAttributeHandler implements Serializable {
         if (clazz == null) {
             throw new IllegalArgumentException("The clazz can not be null");
         }
-        if (cache.containsKey(clazz)) {
+        if (CACHE.containsKey(clazz)) {
             // NO-OP
             return;
         }
@@ -184,7 +184,7 @@ public class DesignAttributeHandler implements Serializable {
                 entry.addAttribute(attribute, getter, setter);
             }
         }
-        cache.put(clazz, entry);
+        CACHE.put(clazz, entry);
     }
 
     /**
@@ -413,7 +413,7 @@ public class DesignAttributeHandler implements Serializable {
     private static Method findSetterForAttribute(Class<?> clazz,
             String attribute) {
         resolveSupportedAttributes(clazz);
-        return cache.get(clazz).getSetter(attribute);
+        return CACHE.get(clazz).getSetter(attribute);
     }
 
     /**
@@ -429,7 +429,7 @@ public class DesignAttributeHandler implements Serializable {
     private static Method findGetterForAttribute(Class<?> clazz,
             String attribute) {
         resolveSupportedAttributes(clazz);
-        return cache.get(clazz).getGetter(attribute);
+        return CACHE.get(clazz).getGetter(attribute);
     }
 
     /**
diff --git a/server/src/main/java/com/vaadin/ui/declarative/converters/DesignResourceConverter.java b/server/src/main/java/com/vaadin/ui/declarative/converters/DesignResourceConverter.java
index 11ed3c259b..46eecde33f 100644
--- a/server/src/main/java/com/vaadin/ui/declarative/converters/DesignResourceConverter.java
+++ b/server/src/main/java/com/vaadin/ui/declarative/converters/DesignResourceConverter.java
@@ -185,22 +185,22 @@ public class DesignResourceConverter implements Converter<String, Resource> {
             return ((ExternalResource) value).getURL();
         }
 
-        private static final Map<Class<? extends Resource>, ResourceConverterByProtocol> typeToConverter = new HashMap<>();
+        private static final Map<Class<? extends Resource>, ResourceConverterByProtocol> TYPE_TO_CONVERTER = new HashMap<>();
 
         static {
-            typeToConverter.put(ExternalResource.class, HTTP);
+            TYPE_TO_CONVERTER.put(ExternalResource.class, HTTP);
             // ^ any of non-specialized would actually work
-            typeToConverter.put(ThemeResource.class, THEME);
-            typeToConverter.put(FontIcon.class, FONTICON);
-            typeToConverter.put(FileResource.class, FILE);
+            TYPE_TO_CONVERTER.put(ThemeResource.class, THEME);
+            TYPE_TO_CONVERTER.put(FontIcon.class, FONTICON);
+            TYPE_TO_CONVERTER.put(FileResource.class, FILE);
 
         }
 
         public static ResourceConverterByProtocol byType(
                 Class<? extends Resource> resourceType) {
-            for (Class<?> type : typeToConverter.keySet()) {
+            for (Class<?> type : TYPE_TO_CONVERTER.keySet()) {
                 if (type.isAssignableFrom(resourceType)) {
-                    return typeToConverter.get(type);
+                    return TYPE_TO_CONVERTER.get(type);
                 }
             }
             return null;
diff --git a/server/src/main/java/com/vaadin/util/CurrentInstance.java b/server/src/main/java/com/vaadin/util/CurrentInstance.java
index 8c3d93993a..0c15abc9ae 100644
--- a/server/src/main/java/com/vaadin/util/CurrentInstance.java
+++ b/server/src/main/java/com/vaadin/util/CurrentInstance.java
@@ -58,7 +58,7 @@ public class CurrentInstance implements Serializable {
 
     private final WeakReference<Object> instance;
 
-    private static final ThreadLocal<Map<Class<?>, CurrentInstance>> instances = new ThreadLocal<>();
+    private static final ThreadLocal<Map<Class<?>, CurrentInstance>> INSTANCES = new ThreadLocal<>();
 
     private CurrentInstance(Object instance) {
         this.instance = new WeakReference<>(instance);
@@ -73,7 +73,7 @@ public class CurrentInstance implements Serializable {
      *         if there is no current instance.
      */
     public static <T> T get(Class<T> type) {
-        Map<Class<?>, CurrentInstance> map = instances.get();
+        Map<Class<?>, CurrentInstance> map = INSTANCES.get();
         if (map == null) {
             return null;
         }
@@ -97,7 +97,7 @@ public class CurrentInstance implements Serializable {
                 removeStaleInstances(map);
 
                 if (map.isEmpty()) {
-                    instances.remove();
+                    INSTANCES.remove();
                 }
 
                 return null;
@@ -135,14 +135,14 @@ public class CurrentInstance implements Serializable {
      *            the actual instance
      */
     public static <T> CurrentInstance set(Class<T> type, T instance) {
-        Map<Class<?>, CurrentInstance> map = instances.get();
+        Map<Class<?>, CurrentInstance> map = INSTANCES.get();
         CurrentInstance previousInstance = null;
         if (instance == null) {
             // remove the instance
             if (map != null) {
                 previousInstance = map.remove(type);
                 if (map.isEmpty()) {
-                    instances.remove();
+                    INSTANCES.remove();
                     map = null;
                 }
             }
@@ -150,7 +150,7 @@ public class CurrentInstance implements Serializable {
             assert type.isInstance(instance) : "Invald instance type";
             if (map == null) {
                 map = new HashMap<>();
-                instances.set(map);
+                INSTANCES.set(map);
             }
 
             previousInstance = map.put(type, new CurrentInstance(instance));
@@ -165,7 +165,7 @@ public class CurrentInstance implements Serializable {
      * Clears all current instances.
      */
     public static void clearAll() {
-        instances.remove();
+        INSTANCES.remove();
     }
 
     /**
@@ -220,7 +220,7 @@ public class CurrentInstance implements Serializable {
      * @return a map containing the current instances
      */
     public static Map<Class<?>, CurrentInstance> getInstances() {
-        Map<Class<?>, CurrentInstance> map = instances.get();
+        Map<Class<?>, CurrentInstance> map = INSTANCES.get();
         if (map == null) {
             return Collections.emptyMap();
         } else {
@@ -237,7 +237,7 @@ public class CurrentInstance implements Serializable {
             if (removeStale) {
                 removeStaleInstances(map);
                 if (map.isEmpty()) {
-                    instances.remove();
+                    INSTANCES.remove();
                 }
             }
             return copy;
diff --git a/server/src/main/java/com/vaadin/util/FileTypeResolver.java b/server/src/main/java/com/vaadin/util/FileTypeResolver.java
index 48d7916967..8abaec0490 100644
--- a/server/src/main/java/com/vaadin/util/FileTypeResolver.java
+++ b/server/src/main/java/com/vaadin/util/FileTypeResolver.java
@@ -54,7 +54,7 @@ public class FileTypeResolver implements Serializable {
     /**
      * Initial file extension to mime-type mapping.
      */
-    private static final String initialExtToMIMEMap = "application/cu-seeme                            csm cu,"
+    private static final String INITIAL_EXT_TO_MIME_MAP = "application/cu-seeme                            csm cu,"
             + "application/dsptype                             tsp,"
             + "application/futuresplash                        spl,"
             + "application/mac-binhex40                        hqx,"
@@ -221,7 +221,7 @@ public class FileTypeResolver implements Serializable {
     static {
 
         // Initialize extension to MIME map
-        final StringTokenizer lines = new StringTokenizer(initialExtToMIMEMap,
+        final StringTokenizer lines = new StringTokenizer(INITIAL_EXT_TO_MIME_MAP,
                 ",");
         while (lines.hasMoreTokens()) {
             final String line = lines.nextToken();
@@ -356,24 +356,24 @@ public class FileTypeResolver implements Serializable {
      * @param extension
      *            the filename extension to be associated with
      *            <code>MIMEType</code>.
-     * @param MIMEType
+     * @param mimeType
      *            the new mime-type for <code>extension</code>.
      */
-    public static void addExtension(String extension, String MIMEType) {
-        EXT_TO_MIME_MAP.put(extension.toLowerCase(Locale.ROOT), MIMEType);
+    public static void addExtension(String extension, String mimeType) {
+        EXT_TO_MIME_MAP.put(extension.toLowerCase(Locale.ROOT), mimeType);
     }
 
     /**
      * Adds a icon for the given mime-type. If the mime-type also has a
      * corresponding icon, it is replaced with the new icon.
      *
-     * @param MIMEType
+     * @param mimeType
      *            the mime-type whose icon is to be changed.
      * @param icon
      *            the new icon to be associated with <code>MIMEType</code>.
      */
-    public static void addIcon(String MIMEType, Resource icon) {
-        MIME_TO_ICON_MAP.put(MIMEType, icon);
+    public static void addIcon(String mimeType, Resource icon) {
+        MIME_TO_ICON_MAP.put(mimeType, icon);
     }
 
     /**
diff --git a/server/src/main/java/com/vaadin/util/TimeZoneUtil.java b/server/src/main/java/com/vaadin/util/TimeZoneUtil.java
index c3c25b21e4..fb56c3688e 100644
--- a/server/src/main/java/com/vaadin/util/TimeZoneUtil.java
+++ b/server/src/main/java/com/vaadin/util/TimeZoneUtil.java
@@ -104,7 +104,7 @@ public final class TimeZoneUtil implements Serializable {
         }
         info.id = zoneId.getId();
         info.transitions = transitionsList.stream().mapToLong(l -> l).toArray();
-        info.std_offset = (int) Duration.ofMillis(timeZone.getRawOffset())
+        info.stdOffset = (int) Duration.ofMillis(timeZone.getRawOffset())
                 .toMinutes();
         info.names = new String[] {
                 timeZone.getDisplayName(false, TimeZone.SHORT, locale),
@@ -119,7 +119,7 @@ public final class TimeZoneUtil implements Serializable {
         JreJsonFactory factory = new JreJsonFactory();
         JsonObject object = factory.createObject();
         object.put("id", info.id);
-        object.put("std_offset", info.std_offset);
+        object.put("std_offset", info.stdOffset);
         object.put("names", getArray(factory, info.names));
         object.put("transitions", getArray(factory, info.transitions));
         return JsonUtil.stringify(object);
@@ -143,7 +143,7 @@ public final class TimeZoneUtil implements Serializable {
 
     private static class TimeZoneInfo implements Serializable {
         String id;
-        int std_offset;
+        int stdOffset;
         String[] names;
         long[] transitions;
     }
diff --git a/server/src/test/java/com/vaadin/data/BeanPropertySetTest.java b/server/src/test/java/com/vaadin/data/BeanPropertySetTest.java
index 7b492ad012..d7bc8f4c44 100644
--- a/server/src/test/java/com/vaadin/data/BeanPropertySetTest.java
+++ b/server/src/test/java/com/vaadin/data/BeanPropertySetTest.java
@@ -66,7 +66,7 @@ public class BeanPropertySetTest {
         // Simulate deserializing into a different JVM by clearing the instance
         // map
         Field instancesField = BeanPropertySet.class
-                .getDeclaredField("instances");
+                .getDeclaredField("INSTANCES");
         instancesField.setAccessible(true);
         Map<?, ?> instances = (Map<?, ?>) instancesField.get(null);
         instances.clear();
diff --git a/server/src/test/java/com/vaadin/server/AbstractClientConnectorTest.java b/server/src/test/java/com/vaadin/server/AbstractClientConnectorTest.java
index b4e4f95194..368595ef27 100644
--- a/server/src/test/java/com/vaadin/server/AbstractClientConnectorTest.java
+++ b/server/src/test/java/com/vaadin/server/AbstractClientConnectorTest.java
@@ -88,7 +88,7 @@ public class AbstractClientConnectorTest {
             NoSuchFieldException, SecurityException, InterruptedException,
             ClassNotFoundException {
         Field stateTypeCacheField = AbstractClientConnector.class
-                .getDeclaredField("stateTypeCache");
+                .getDeclaredField("STATE_TYPE_CACHE");
         stateTypeCacheField.setAccessible(true);
         Map<Class<?>, ?> stateTypeCache = (Map<Class<?>, ?>) stateTypeCacheField
                 .get(null);
diff --git a/server/src/test/java/com/vaadin/util/CurrentInstanceTest.java b/server/src/test/java/com/vaadin/util/CurrentInstanceTest.java
index 74b8ce7e6d..34d8de2fc6 100644
--- a/server/src/test/java/com/vaadin/util/CurrentInstanceTest.java
+++ b/server/src/test/java/com/vaadin/util/CurrentInstanceTest.java
@@ -77,7 +77,7 @@ public class CurrentInstanceTest {
     private ThreadLocal<Map<Class<?>, CurrentInstance>> getInternalCurrentInstanceVariable()
             throws SecurityException, NoSuchFieldException,
             IllegalAccessException {
-        Field f = CurrentInstance.class.getDeclaredField("instances");
+        Field f = CurrentInstance.class.getDeclaredField("INSTANCES");
         f.setAccessible(true);
         return (ThreadLocal<Map<Class<?>, CurrentInstance>>) f.get(null);
     }