Use final modifier where appropriate

Change-Id: I80b73b653e97904605dc62484a7448f3bfbf7226

31 files changed, 39 insertions, 39 deletions

diff --git a/server/src/test/java/com/vaadin/data/BinderMultiSelectTest.java b/server/src/test/java/com/vaadin/data/BinderMultiSelectTest.java
index 3b35f86144..f59c89e1d8 100644
--- a/server/src/test/java/com/vaadin/data/BinderMultiSelectTest.java
+++ b/server/src/test/java/com/vaadin/data/BinderMultiSelectTest.java
@@ -54,7 +54,7 @@ public class BinderMultiSelectTest
         }
     }
 
-    private Binder<AtomicReference<String>> converterBinder = new Binder<>();
+    private final Binder<AtomicReference<String>> converterBinder = new Binder<>();
 
     private CheckBoxGroup<TestEnum> select;
 
diff --git a/server/src/test/java/com/vaadin/data/Jsr303Test.java b/server/src/test/java/com/vaadin/data/Jsr303Test.java
index da30f56743..016018a6b3 100644
--- a/server/src/test/java/com/vaadin/data/Jsr303Test.java
+++ b/server/src/test/java/com/vaadin/data/Jsr303Test.java
@@ -78,7 +78,7 @@ public class Jsr303Test {
 
     public static class Jsr303UnitTest implements UnitTest {
 
-        private TextField nameField = new TextField();
+        private final TextField nameField = new TextField();
 
         @Override
         public void execute() {
diff --git a/server/src/test/java/com/vaadin/data/validator/StringLengthValidatorTest.java b/server/src/test/java/com/vaadin/data/validator/StringLengthValidatorTest.java
index dd2b1be50b..7fb1c2ff76 100644
--- a/server/src/test/java/com/vaadin/data/validator/StringLengthValidatorTest.java
+++ b/server/src/test/java/com/vaadin/data/validator/StringLengthValidatorTest.java
@@ -7,7 +7,7 @@ import org.junit.Test;
 
 public class StringLengthValidatorTest extends ValidatorTestBase {
 
-    private static String LONG_STRING = Stream.generate(() -> "x").limit(1000)
+    private static final String LONG_STRING = Stream.generate(() -> "x").limit(1000)
             .collect(Collectors.joining());
 
     @Test
diff --git a/server/src/test/java/com/vaadin/server/AbstractDeploymentConfigurationTest.java b/server/src/test/java/com/vaadin/server/AbstractDeploymentConfigurationTest.java
index c274bf35c3..2d4e7fad0a 100644
--- a/server/src/test/java/com/vaadin/server/AbstractDeploymentConfigurationTest.java
+++ b/server/src/test/java/com/vaadin/server/AbstractDeploymentConfigurationTest.java
@@ -95,7 +95,7 @@ public class AbstractDeploymentConfigurationTest {
     private static class DeploymentConfigImpl
             extends AbstractDeploymentConfiguration {
 
-        private Properties properties;
+        private final Properties properties;
 
         DeploymentConfigImpl(Properties props) {
             properties = props;
diff --git a/server/src/test/java/com/vaadin/server/DownloadStreamTest.java b/server/src/test/java/com/vaadin/server/DownloadStreamTest.java
index f302163ef7..81f45f6173 100644
--- a/server/src/test/java/com/vaadin/server/DownloadStreamTest.java
+++ b/server/src/test/java/com/vaadin/server/DownloadStreamTest.java
@@ -13,7 +13,7 @@ import org.junit.Before;
 import org.junit.Test;
 
 public class DownloadStreamTest {
-    private String filename = "日本語.png";
+    private final String filename = "日本語.png";
     private DownloadStream stream;
 
     @Before
diff --git a/server/src/test/java/com/vaadin/server/MockVaadinSession.java b/server/src/test/java/com/vaadin/server/MockVaadinSession.java
index 04d516ecb4..07854560b3 100644
--- a/server/src/test/java/com/vaadin/server/MockVaadinSession.java
+++ b/server/src/test/java/com/vaadin/server/MockVaadinSession.java
@@ -66,5 +66,5 @@ public class MockVaadinSession extends VaadinSession {
 
     private int closeCount;
 
-    private ReentrantLock lock = new ReentrantLock();
+    private final ReentrantLock lock = new ReentrantLock();
 }
diff --git a/server/src/test/java/com/vaadin/server/communication/FileUploadHandlerTest.java b/server/src/test/java/com/vaadin/server/communication/FileUploadHandlerTest.java
index 3726ed7cea..60b2b2a02d 100644
--- a/server/src/test/java/com/vaadin/server/communication/FileUploadHandlerTest.java
+++ b/server/src/test/java/com/vaadin/server/communication/FileUploadHandlerTest.java
@@ -58,7 +58,7 @@ public class FileUploadHandlerTest {
     @Mock
     private OutputStream responseOutput;
 
-    private int uiId = 123;
+    private final int uiId = 123;
     private final String connectorId = "connectorId";
     private final String variableName = "name";
     private final String expectedSecurityKey = "key";
diff --git a/server/src/test/java/com/vaadin/server/data/DataCommunicatorTest.java b/server/src/test/java/com/vaadin/server/data/DataCommunicatorTest.java
index b82d571f9b..c9a30fa517 100644
--- a/server/src/test/java/com/vaadin/server/data/DataCommunicatorTest.java
+++ b/server/src/test/java/com/vaadin/server/data/DataCommunicatorTest.java
@@ -85,7 +85,7 @@ public class DataCommunicatorTest {
         }
     }
 
-    private MockVaadinSession session = new MockVaadinSession(
+    private final MockVaadinSession session = new MockVaadinSession(
             Mockito.mock(VaadinService.class));
 
     @Test
diff --git a/server/src/test/java/com/vaadin/server/data/datasource/StrBean.java b/server/src/test/java/com/vaadin/server/data/datasource/StrBean.java
index 24f478ad47..44650d63bb 100644
--- a/server/src/test/java/com/vaadin/server/data/datasource/StrBean.java
+++ b/server/src/test/java/com/vaadin/server/data/datasource/StrBean.java
@@ -7,7 +7,7 @@ import java.util.Random;
 
 class StrBean implements Serializable {
 
-    private static String[] values = new String[] { "Foo", "Bar", "Baz" };
+    private static final String[] values = new String[] { "Foo", "Bar", "Baz" };
 
     private String value;
     private final int id;
diff --git a/server/src/test/java/com/vaadin/tests/data/bean/AnotherTestEnum.java b/server/src/test/java/com/vaadin/tests/data/bean/AnotherTestEnum.java
index fc8f22a947..934a2ce696 100644
--- a/server/src/test/java/com/vaadin/tests/data/bean/AnotherTestEnum.java
+++ b/server/src/test/java/com/vaadin/tests/data/bean/AnotherTestEnum.java
@@ -3,7 +3,7 @@ package com.vaadin.tests.data.bean;
 public enum AnotherTestEnum {
     ONE("ONE"), TWO("TWO");
 
-    private String id;
+    private final String id;
 
     private AnotherTestEnum(String id) {
         this.id = id;
diff --git a/server/src/test/java/com/vaadin/tests/data/bean/BeanToValidate.java b/server/src/test/java/com/vaadin/tests/data/bean/BeanToValidate.java
index 9f0b244360..23270cab5e 100644
--- a/server/src/test/java/com/vaadin/tests/data/bean/BeanToValidate.java
+++ b/server/src/test/java/com/vaadin/tests/data/bean/BeanToValidate.java
@@ -42,7 +42,7 @@ public class BeanToValidate {
     @Valid
     private Address address;
 
-    private String readOnlyProperty = "READONLY DATA";
+    private final String readOnlyProperty = "READONLY DATA";
 
     private String writeOnlyProperty;
 
diff --git a/server/src/test/java/com/vaadin/tests/data/bean/Country.java b/server/src/test/java/com/vaadin/tests/data/bean/Country.java
index 159333212f..c7795d5f6d 100644
--- a/server/src/test/java/com/vaadin/tests/data/bean/Country.java
+++ b/server/src/test/java/com/vaadin/tests/data/bean/Country.java
@@ -5,7 +5,7 @@ public enum Country {
     FINLAND("Finland"), SWEDEN("Sweden"), USA("USA"), RUSSIA(
             "Russia"), NETHERLANDS("Netherlands"), SOUTH_AFRICA("South Africa");
 
-    private String name;
+    private final String name;
 
     private Country(String name) {
         this.name = name;
diff --git a/server/src/test/java/com/vaadin/tests/data/bean/Sex.java b/server/src/test/java/com/vaadin/tests/data/bean/Sex.java
index a4e3f20a11..489588c640 100644
--- a/server/src/test/java/com/vaadin/tests/data/bean/Sex.java
+++ b/server/src/test/java/com/vaadin/tests/data/bean/Sex.java
@@ -3,7 +3,7 @@ package com.vaadin.tests.data.bean;
 public enum Sex {
     MALE("Male"), FEMALE("Female"), UNKNOWN("Unknown");
 
-    private String stringRepresentation;
+    private final String stringRepresentation;
 
     private Sex(String stringRepresentation) {
         this.stringRepresentation = stringRepresentation;
diff --git a/server/src/test/java/com/vaadin/tests/data/bean/TestEnum.java b/server/src/test/java/com/vaadin/tests/data/bean/TestEnum.java
index bf6f721052..f79298b6ad 100644
--- a/server/src/test/java/com/vaadin/tests/data/bean/TestEnum.java
+++ b/server/src/test/java/com/vaadin/tests/data/bean/TestEnum.java
@@ -3,7 +3,7 @@ package com.vaadin.tests.data.bean;
 public enum TestEnum {
     ONE("1"), TWO("2");
 
-    private String id;
+    private final String id;
 
     private TestEnum(String id) {
         this.id = id;
diff --git a/server/src/test/java/com/vaadin/tests/data/converter/StringToBooleanConverterTest.java b/server/src/test/java/com/vaadin/tests/data/converter/StringToBooleanConverterTest.java
index 4de05b9f09..d3d539ae8f 100644
--- a/server/src/test/java/com/vaadin/tests/data/converter/StringToBooleanConverterTest.java
+++ b/server/src/test/java/com/vaadin/tests/data/converter/StringToBooleanConverterTest.java
@@ -21,7 +21,7 @@ public class StringToBooleanConverterTest extends AbstractStringConverterTest {
             getErrorMessage(), "yes", "no");
     private StringToBooleanConverter emptyTrueConverter = new StringToBooleanConverter(
             getErrorMessage(), "", "ABSENT");
-    private StringToBooleanConverter localeConverter = new StringToBooleanConverter(
+    private final StringToBooleanConverter localeConverter = new StringToBooleanConverter(
             getErrorMessage()) {
         @Override
         public String getFalseString(Locale locale) {
diff --git a/server/src/test/java/com/vaadin/tests/design/DeclarativeTestBase.java b/server/src/test/java/com/vaadin/tests/design/DeclarativeTestBase.java
index 2b73408abc..3e8e4dccd6 100644
--- a/server/src/test/java/com/vaadin/tests/design/DeclarativeTestBase.java
+++ b/server/src/test/java/com/vaadin/tests/design/DeclarativeTestBase.java
@@ -31,7 +31,7 @@ import com.vaadin.ui.Flash;
 public abstract class DeclarativeTestBase<T extends Component>
         extends DeclarativeTestBaseBase<T> {
 
-    private static boolean debug = false;
+    private static final boolean debug = false;
 
     private final Map<Class<?>, EqualsAsserter<?>> comparators = new HashMap<>();
     private static final EqualsAsserter standardEqualsComparator = (EqualsAsserter<Object>) Assert::assertEquals;
diff --git a/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithAnnotation.java b/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithAnnotation.java
index 28d419b27e..b1f6297d9e 100644
--- a/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithAnnotation.java
+++ b/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithAnnotation.java
@@ -18,7 +18,7 @@ package com.vaadin.tests.design.designroot;
 import com.vaadin.ui.TextField;
 
 public class ExtendedDesignWithAnnotation extends DesignWithAnnotation {
-    private TextField customField = new TextField();
+    private final TextField customField = new TextField();
 
     public ExtendedDesignWithAnnotation() {
         customField.setPlaceholder("Something");
diff --git a/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithEmptyAnnotation.java b/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithEmptyAnnotation.java
index ea23f847cf..cfea7a6fda 100644
--- a/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithEmptyAnnotation.java
+++ b/server/src/test/java/com/vaadin/tests/design/designroot/ExtendedDesignWithEmptyAnnotation.java
@@ -23,7 +23,7 @@ import com.vaadin.ui.TextField;
 public class ExtendedDesignWithEmptyAnnotation
         extends DesignWithEmptyAnnotation {
 
-    private TextField customField = new TextField();
+    private final TextField customField = new TextField();
 
     public ExtendedDesignWithEmptyAnnotation() {
         super();
diff --git a/server/src/test/java/com/vaadin/tests/design/nested/NestedCustomLayoutsTest.java b/server/src/test/java/com/vaadin/tests/design/nested/NestedCustomLayoutsTest.java
index 6479e1995a..341397ff81 100644
--- a/server/src/test/java/com/vaadin/tests/design/nested/NestedCustomLayoutsTest.java
+++ b/server/src/test/java/com/vaadin/tests/design/nested/NestedCustomLayoutsTest.java
@@ -49,7 +49,7 @@ import com.vaadin.ui.declarative.Design;
  */
 public class NestedCustomLayoutsTest {
 
-    private static String PACKAGE_MAPPING = "com_vaadin_tests_design_nested_customlayouts:com.vaadin.tests.design.nested.customlayouts";
+    private static final String PACKAGE_MAPPING = "com_vaadin_tests_design_nested_customlayouts:com.vaadin.tests.design.nested.customlayouts";
 
     @Test
     public void testNestedLayouts() throws IOException {
diff --git a/server/src/test/java/com/vaadin/tests/server/ClassesSerializableTest.java b/server/src/test/java/com/vaadin/tests/server/ClassesSerializableTest.java
index 865856f79c..e33f8373ce 100644
--- a/server/src/test/java/com/vaadin/tests/server/ClassesSerializableTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/ClassesSerializableTest.java
@@ -38,11 +38,11 @@ public class ClassesSerializableTest {
      * JARs that will be scanned for classes to test, in addition to classpath
      * directories.
      */
-    private static String JAR_PATTERN = ".*vaadin.*\\.jar";
+    private static final String JAR_PATTERN = ".*vaadin.*\\.jar";
 
-    private static String[] BASE_PACKAGES = { "com.vaadin" };
+    private static final String[] BASE_PACKAGES = { "com.vaadin" };
 
-    private static String[] EXCLUDED_PATTERNS = { "com\\.vaadin\\.demo\\..*", //
+    private static final String[] EXCLUDED_PATTERNS = { "com\\.vaadin\\.demo\\..*", //
             "com\\.vaadin\\.external\\.org\\.apache\\.commons\\.fileupload\\..*", //
             "com\\.vaadin\\.launcher\\..*", //
             "com\\.vaadin\\.client\\..*", //
diff --git a/server/src/test/java/com/vaadin/tests/server/CsrfTokenMissingTest.java b/server/src/test/java/com/vaadin/tests/server/CsrfTokenMissingTest.java
index 22d2fb283b..2f4ba832d3 100644
--- a/server/src/test/java/com/vaadin/tests/server/CsrfTokenMissingTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/CsrfTokenMissingTest.java
@@ -184,7 +184,7 @@ public class CsrfTokenMissingTest {
                 rpcRequest.getCsrfToken());
     }
 
-    private static Logger LOGGER = Logger
+    private static final Logger LOGGER = Logger
             .getLogger(CsrfTokenMissingTest.class.getName());
     static {
         LOGGER.setLevel(Level.ALL);
diff --git a/server/src/test/java/com/vaadin/tests/server/clientconnector/AttachDetachListenersTest.java b/server/src/test/java/com/vaadin/tests/server/clientconnector/AttachDetachListenersTest.java
index b870e0ab4f..7a44e861da 100644
--- a/server/src/test/java/com/vaadin/tests/server/clientconnector/AttachDetachListenersTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/clientconnector/AttachDetachListenersTest.java
@@ -151,7 +151,7 @@ public class AttachDetachListenersTest {
     public static class EventEquals<E extends ConnectorEvent>
             implements IArgumentMatcher {
 
-        private E expected;
+        private final E expected;
 
         public EventEquals(E expected) {
             this.expected = expected;
diff --git a/server/src/test/java/com/vaadin/tests/server/component/StateGetDoesNotMarkDirtyTest.java b/server/src/test/java/com/vaadin/tests/server/component/StateGetDoesNotMarkDirtyTest.java
index 57647f1e6a..70b7b0b77c 100644
--- a/server/src/test/java/com/vaadin/tests/server/component/StateGetDoesNotMarkDirtyTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/component/StateGetDoesNotMarkDirtyTest.java
@@ -19,7 +19,7 @@ import com.vaadin.ui.UI;
 
 public class StateGetDoesNotMarkDirtyTest {
 
-    private Set<String> excludedMethods = new HashSet<>();
+    private final Set<String> excludedMethods = new HashSet<>();
 
     @Before
     public void setUp() {
diff --git a/server/src/test/java/com/vaadin/tests/server/component/csslayout/AddComponentsTest.java b/server/src/test/java/com/vaadin/tests/server/component/csslayout/AddComponentsTest.java
index 4da1b1380a..9fe1e4210a 100644
--- a/server/src/test/java/com/vaadin/tests/server/component/csslayout/AddComponentsTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/component/csslayout/AddComponentsTest.java
@@ -16,7 +16,7 @@ import com.vaadin.ui.Layout;
 
 public class AddComponentsTest {
 
-    private Component[] children = new Component[] { new Label("A"),
+    private final Component[] children = new Component[] { new Label("A"),
             new Label("B"), new Label("C"), new Label("D") };
 
     @Test
diff --git a/server/src/test/java/com/vaadin/tests/server/component/customlayout/CustomLayoutTest.java b/server/src/test/java/com/vaadin/tests/server/component/customlayout/CustomLayoutTest.java
index d4880a3d2e..9d60628e12 100644
--- a/server/src/test/java/com/vaadin/tests/server/component/customlayout/CustomLayoutTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/component/customlayout/CustomLayoutTest.java
@@ -142,6 +142,6 @@ public class CustomLayoutTest {
 
         private int readCount;
         private boolean isClosed;
-        private int maxArrayLength;
+        private final int maxArrayLength;
     }
 }
diff --git a/server/src/test/java/com/vaadin/tests/server/component/menubar/MenuBarIdsTest.java b/server/src/test/java/com/vaadin/tests/server/component/menubar/MenuBarIdsTest.java
index f42b9a5683..bd8c2dd443 100644
--- a/server/src/test/java/com/vaadin/tests/server/component/menubar/MenuBarIdsTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/component/menubar/MenuBarIdsTest.java
@@ -23,7 +23,7 @@ public class MenuBarIdsTest implements Command {
     private MenuItem menuFileOpen;
     private MenuItem menuFileSave;
     private MenuItem menuFileExit;
-    private Set<MenuItem> menuItems = new HashSet<>();
+    private final Set<MenuItem> menuItems = new HashSet<>();
 
     private MenuBar menuBar;
 
diff --git a/server/src/test/java/com/vaadin/tests/server/component/ui/CustomUIClassLoaderTest.java b/server/src/test/java/com/vaadin/tests/server/component/ui/CustomUIClassLoaderTest.java
index f7a78b34ec..4e4f5160ba 100644
--- a/server/src/test/java/com/vaadin/tests/server/component/ui/CustomUIClassLoaderTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/component/ui/CustomUIClassLoaderTest.java
@@ -37,7 +37,7 @@ public class CustomUIClassLoaderTest {
      */
     public class LoggingClassLoader extends ClassLoader {
 
-        private List<String> requestedClasses = new ArrayList<>();
+        private final List<String> requestedClasses = new ArrayList<>();
 
         @Override
         protected synchronized Class<?> loadClass(String name, boolean resolve)
diff --git a/server/src/test/java/com/vaadin/tests/server/component/window/AttachDetachWindowTest.java b/server/src/test/java/com/vaadin/tests/server/component/window/AttachDetachWindowTest.java
index 5d0c0cc55d..872683cec3 100644
--- a/server/src/test/java/com/vaadin/tests/server/component/window/AttachDetachWindowTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/component/window/AttachDetachWindowTest.java
@@ -21,7 +21,7 @@ import com.vaadin.ui.Window;
 
 public class AttachDetachWindowTest {
 
-    private VaadinSession testApp = new AlwaysLockedVaadinSession(null);
+    private final VaadinSession testApp = new AlwaysLockedVaadinSession(null);
 
     private interface TestContainer {
         public boolean attachCalled();
@@ -36,7 +36,7 @@ public class AttachDetachWindowTest {
     private class TestWindow extends Window implements TestContainer {
         boolean windowAttachCalled = false;
         boolean windowDetachCalled = false;
-        private TestContent testContent = new TestContent();
+        private final TestContent testContent = new TestContent();
 
         TestWindow() {
             setContent(testContent);
@@ -81,7 +81,7 @@ public class AttachDetachWindowTest {
         boolean contentAttachCalled = false;
         boolean childAttachCalled = false;
 
-        private Label child = new Label() {
+        private final Label child = new Label() {
             @Override
             public void attach() {
                 super.attach();
@@ -115,7 +115,7 @@ public class AttachDetachWindowTest {
     private class TestUI extends UI implements TestContainer {
         boolean rootAttachCalled = false;
         boolean rootDetachCalled = false;
-        private TestContent testContent = new TestContent();
+        private final TestContent testContent = new TestContent();
 
         public TestUI() {
             setContent(testContent);
diff --git a/server/src/test/java/com/vaadin/tests/server/navigator/NavigatorTest.java b/server/src/test/java/com/vaadin/tests/server/navigator/NavigatorTest.java
index be3f402e16..20271defe5 100644
--- a/server/src/test/java/com/vaadin/tests/server/navigator/NavigatorTest.java
+++ b/server/src/test/java/com/vaadin/tests/server/navigator/NavigatorTest.java
@@ -217,7 +217,7 @@ public class NavigatorTest {
             return page;
         }
 
-        private Page page;
+        private final Page page;
     }
 
     private static class TestPage extends Page {
diff --git a/server/src/test/java/com/vaadin/tests/util/MockDeploymentConfiguration.java b/server/src/test/java/com/vaadin/tests/util/MockDeploymentConfiguration.java
index e4665adf52..4f6ea6625d 100644
--- a/server/src/test/java/com/vaadin/tests/util/MockDeploymentConfiguration.java
+++ b/server/src/test/java/com/vaadin/tests/util/MockDeploymentConfiguration.java
@@ -17,10 +17,10 @@ public class MockDeploymentConfiguration
     private int heartbeatInterval = 300;
     private boolean closeIdleSessions = false;
     private PushMode pushMode = PushMode.DISABLED;
-    private Properties initParameters = new Properties();
-    private Map<String, String> applicationOrSystemProperty = new HashMap<>();
+    private final Properties initParameters = new Properties();
+    private final Map<String, String> applicationOrSystemProperty = new HashMap<>();
     private boolean syncIdCheckEnabled = true;
-    private boolean sendUrlsAsParameters = true;
+    private final boolean sendUrlsAsParameters = true;
 
     @Override
     public boolean isProductionMode() {
diff --git a/server/src/test/java/com/vaadin/ui/declarative/DesignTest.java b/server/src/test/java/com/vaadin/ui/declarative/DesignTest.java
index 2b39cc7c51..769a02dedc 100644
--- a/server/src/test/java/com/vaadin/ui/declarative/DesignTest.java
+++ b/server/src/test/java/com/vaadin/ui/declarative/DesignTest.java
@@ -43,9 +43,9 @@ public class DesignTest {
     private static final Charset CP1251_CHARSET = Charset.forName("cp1251");
     private static final Charset UTF8_CHARSET = StandardCharsets.UTF_8;
 
-    private static String NON_ASCII_STRING = "\u043C";
+    private static final String NON_ASCII_STRING = "\u043C";
 
-    private static Charset DEFAULT_CHARSET = Charset.defaultCharset();
+    private static final Charset DEFAULT_CHARSET = Charset.defaultCharset();
 
     @AfterClass
     public static void restoreCharset()