minor cleanup work

core-java-8/.settings/org.eclipse.jdt.core.prefs

@@ -1,4 +1,5 @@
 eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.annotation.inheritNullAnnotations=disabled
 org.eclipse.jdt.core.compiler.annotation.missingNonNullByDefaultAnnotation=ignore
 org.eclipse.jdt.core.compiler.annotation.nonnull=org.eclipse.jdt.annotation.NonNull
 org.eclipse.jdt.core.compiler.annotation.nonnullbydefault=org.eclipse.jdt.annotation.NonNullByDefault
@@ -26,7 +27,7 @@ org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
 org.eclipse.jdt.core.compiler.problem.explicitlyClosedAutoCloseable=ignore
 org.eclipse.jdt.core.compiler.problem.fallthroughCase=ignore
 org.eclipse.jdt.core.compiler.problem.fatalOptionalError=disabled
-org.eclipse.jdt.core.compiler.problem.fieldHiding=error
+org.eclipse.jdt.core.compiler.problem.fieldHiding=warning
 org.eclipse.jdt.core.compiler.problem.finalParameterBound=warning
 org.eclipse.jdt.core.compiler.problem.finallyBlockNotCompletingNormally=warning
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
@@ -35,7 +36,7 @@ org.eclipse.jdt.core.compiler.problem.includeNullInfoFromAsserts=disabled
 org.eclipse.jdt.core.compiler.problem.incompatibleNonInheritedInterfaceMethod=warning
 org.eclipse.jdt.core.compiler.problem.incompleteEnumSwitch=ignore
 org.eclipse.jdt.core.compiler.problem.indirectStaticAccess=ignore
-org.eclipse.jdt.core.compiler.problem.localVariableHiding=error
+org.eclipse.jdt.core.compiler.problem.localVariableHiding=warning
 org.eclipse.jdt.core.compiler.problem.methodWithConstructorName=warning
 org.eclipse.jdt.core.compiler.problem.missingDefaultCase=ignore
 org.eclipse.jdt.core.compiler.problem.missingDeprecatedAnnotation=ignore
@@ -48,6 +49,7 @@ org.eclipse.jdt.core.compiler.problem.missingSynchronizedOnInheritedMethod=ignor
 org.eclipse.jdt.core.compiler.problem.noEffectAssignment=warning
 org.eclipse.jdt.core.compiler.problem.noImplicitStringConversion=warning
 org.eclipse.jdt.core.compiler.problem.nonExternalizedStringLiteral=ignore
+org.eclipse.jdt.core.compiler.problem.nonnullParameterAnnotationDropped=warning
 org.eclipse.jdt.core.compiler.problem.nullAnnotationInferenceConflict=error
 org.eclipse.jdt.core.compiler.problem.nullReference=warning
 org.eclipse.jdt.core.compiler.problem.nullSpecViolation=error
@@ -68,6 +70,7 @@ org.eclipse.jdt.core.compiler.problem.specialParameterHidingField=disabled
 org.eclipse.jdt.core.compiler.problem.staticAccessReceiver=warning
 org.eclipse.jdt.core.compiler.problem.suppressOptionalErrors=disabled
 org.eclipse.jdt.core.compiler.problem.suppressWarnings=enabled
+org.eclipse.jdt.core.compiler.problem.syntacticNullAnalysisForFields=disabled
 org.eclipse.jdt.core.compiler.problem.syntheticAccessEmulation=ignore
 org.eclipse.jdt.core.compiler.problem.typeParameterHiding=error
 org.eclipse.jdt.core.compiler.problem.unavoidableGenericTypeProblems=enabled
@@ -82,6 +85,7 @@ org.eclipse.jdt.core.compiler.problem.unusedDeclaredThrownException=ignore
 org.eclipse.jdt.core.compiler.problem.unusedDeclaredThrownExceptionExemptExceptionAndThrowable=enabled
 org.eclipse.jdt.core.compiler.problem.unusedDeclaredThrownExceptionIncludeDocCommentReference=enabled
 org.eclipse.jdt.core.compiler.problem.unusedDeclaredThrownExceptionWhenOverriding=disabled
+org.eclipse.jdt.core.compiler.problem.unusedExceptionParameter=ignore
 org.eclipse.jdt.core.compiler.problem.unusedImport=warning
 org.eclipse.jdt.core.compiler.problem.unusedLabel=warning
 org.eclipse.jdt.core.compiler.problem.unusedLocal=warning
@@ -91,6 +95,7 @@ org.eclipse.jdt.core.compiler.problem.unusedParameterIncludeDocCommentReference=
 org.eclipse.jdt.core.compiler.problem.unusedParameterWhenImplementingAbstract=disabled
 org.eclipse.jdt.core.compiler.problem.unusedParameterWhenOverridingConcrete=disabled
 org.eclipse.jdt.core.compiler.problem.unusedPrivateMember=warning
+org.eclipse.jdt.core.compiler.problem.unusedTypeParameter=ignore
 org.eclipse.jdt.core.compiler.problem.unusedWarningToken=warning
 org.eclipse.jdt.core.compiler.problem.varargsArgumentNeedCast=warning
 org.eclipse.jdt.core.compiler.source=1.8

core-java-8/src/main/java/com/baeldung/AdderImpl.java

@@ -6,11 +6,12 @@ import java.util.function.Function;
 public class AdderImpl implements Adder {
 
     @Override
-    public  String addWithFunction(Function<String, String> f) {
+    public String addWithFunction(Function<String, String> f) {
         return f.apply("Something ");
     }
 
     @Override
-    public void addWithConsumer(Consumer<Integer> f) {}
+    public void addWithConsumer(Consumer<Integer> f) {
+    }
 
 }

core-java-8/src/main/java/com/baeldung/Foo.java

@@ -5,5 +5,6 @@ public interface Foo {
 
     String method(String string);
 
-    default void defaultMethod() {}
+    default void defaultMethod() {
+    }
 }

core-java-8/src/main/java/com/baeldung/UseFoo.java

@@ -6,34 +6,32 @@ public class UseFoo {
 
     private String value = "Enclosing scope value";
 
-    public String add(String string, Foo foo) {
+    public String add(final String string, final Foo foo) {
         return foo.method(string);
     }
 
-    public String addWithStandardFI(String string, Function<String, String> fn) {
+    public String addWithStandardFI(final String string, final Function<String, String> fn) {
         return fn.apply(string);
     }
 
     public String scopeExperiment() {
-        Foo fooIC = new Foo() {
+        final Foo fooIC = new Foo() {
             String value = "Inner class value";
 
             @Override
-            public String method(String string) {
+            public String method(final String string) {
-                return this.value;
+                return value;
             }
         };
-        String resultIC = fooIC.method("");
+        final String resultIC = fooIC.method("");
 
-        Foo fooLambda = parameter -> {
+        final Foo fooLambda = parameter -> {
-            String value = "Lambda value";
+            final String value = "Lambda value";
             return this.value;
         };
-        String resultLambda = fooLambda.method("");
+        final String resultLambda = fooLambda.method("");
 
-        return "Results: resultIC = " + resultIC +
+        return "Results: resultIC = " + resultIC + ", resultLambda = " + resultLambda;
-                ", resultLambda = " + resultLambda;
     }
 
-    
 }

core-java-8/src/test/java/com/baeldung/java8/Java8FunctionalInteracesLambdasTest.java

@@ -1,15 +1,16 @@
 package com.baeldung.java8;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+
+import java.util.function.Function;
+
+import org.junit.Before;
+import org.junit.Test;
+
 import com.baeldung.Foo;
 import com.baeldung.FooExtended;
 import com.baeldung.UseFoo;
-import org.junit.Before;
-import org.junit.Test;
-
-import java.util.function.Function;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotEquals;
 
 public class Java8FunctionalInteracesLambdasTest {
 
@@ -22,39 +23,35 @@ public class Java8FunctionalInteracesLambdasTest {
 
     @Test
     public void functionalInterfaceInstantiation_whenReturnDefiniteString_thenCorrect() {
-
+        final Foo foo = parameter -> parameter + "from lambda";
-        Foo foo = parameter -> parameter + "from lambda";
+        final String result = useFoo.add("Message ", foo);
-        String result = useFoo.add("Message ", foo);
 
         assertEquals("Message from lambda", result);
     }
 
     @Test
     public void standardFIParameter_whenReturnDefiniteString_thenCorrect() {
-
+        final Function<String, String> fn = parameter -> parameter + "from lambda";
-        Function<String, String> fn = parameter -> parameter + "from lambda";
+        final String result = useFoo.addWithStandardFI("Message ", fn);
-        String result = useFoo.addWithStandardFI("Message ", fn);
 
         assertEquals("Message from lambda", result);
     }
 
     @Test
     public void defaultMethodFromExtendedInterface_whenReturnDefiniteString_thenCorrect() {
-
+        final FooExtended fooExtended = string -> string;
-        FooExtended fooExtended = string -> string;
+        final String result = fooExtended.defaultMethod();
-        String result = fooExtended.defaultMethod();
 
         assertEquals("String from Bar", result);
     }
 
     @Test
     public void lambdaAndInnerClassInstantiation_whenReturnSameString_thenCorrect() {
+        final Foo foo = parameter -> parameter + "from Foo";
 
-        Foo foo = parameter -> parameter + "from Foo";
+        final Foo fooByIC = new Foo() {
-
-        Foo fooByIC = new Foo() {
             @Override
-            public String method(String string) {
+            public String method(final String string) {
                 return string + "from Foo";
             }
         };
@@ -64,35 +61,32 @@ public class Java8FunctionalInteracesLambdasTest {
 
     @Test
     public void accessVariablesFromDifferentScopes_whenReturnPredefinedString_thenCorrect() {
-
+        assertEquals("Results: resultIC = Inner class value, resultLambda = Enclosing scope value", useFoo.scopeExperiment());
-        assertEquals("Results: resultIC = Inner class value, resultLambda = Enclosing scope value",
-                useFoo.scopeExperiment());
     }
 
     @Test
     public void shorteningLambdas_whenReturnEqualsResults_thenCorrect() {
+        final Foo foo = parameter -> buildString(parameter);
 
-        Foo foo = parameter -> buildString(parameter);
+        final Foo fooHuge = parameter -> {
-
+            final String result = "Something " + parameter;
-        Foo fooHuge = parameter -> { String result = "Something " + parameter;
+            // many lines of code
-            //many lines of code
             return result;
         };
 
         assertEquals(foo.method("Something"), fooHuge.method("Something"));
     }
 
-    private String buildString(String parameter) {
+    private String buildString(final String parameter) {
-        String result = "Something " + parameter;
+        final String result = "Something " + parameter;
-        //many lines of code
+        // many lines of code
         return result;
     }
 
     @Test
     public void mutatingOfEffectivelyFinalVariable_whenNotEquals_thenCorrect() {
-
+        final int[] total = new int[1];
-        int[] total = new int[1];
+        final Runnable r = () -> total[0]++;
-        Runnable r = () -> total[0]++;
         r.run();
 
         assertNotEquals(0, total[0]);

core-java-8/src/test/java/com/baeldung/java8/Java8SortUnitTest.java

@@ -6,10 +6,10 @@ import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 
-import com.baeldung.java8.entity.Human;
 import org.junit.Assert;
 import org.junit.Test;
 
+import com.baeldung.java8.entity.Human;
 import com.google.common.collect.Lists;
 import com.google.common.primitives.Ints;