8291954: Use Optional.isEmpty instead of !Optional.isPresent in java.base

Reviewed-by: jpai, alanb, lancea, rriggs, bpb

src/java.base/share/classes/java/lang/Runtime.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1995, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1995, 2022, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2019, Azul Systems, Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -36,7 +36,6 @@ import java.util.Optional;
 import java.util.StringTokenizer;
 
 import jdk.internal.access.SharedSecrets;
-import jdk.internal.loader.NativeLibrary;
 import jdk.internal.reflect.CallerSensitive;
 import jdk.internal.reflect.Reflection;
 
@@ -1075,7 +1074,7 @@ public class Runtime {
                     m.group(VersionPattern.OPT_GROUP));
 
             // empty '+'
-            if (!build.isPresent()) {
+            if (build.isEmpty()) {
                 if (m.group(VersionPattern.PLUS_GROUP) != null) {
                     if (optional.isPresent()) {
                         if (pre.isPresent())
@@ -1087,7 +1086,7 @@ public class Runtime {
                             + " build or optional components: '" + s + "'");
                     }
                 } else {
-                    if (optional.isPresent() && !pre.isPresent()) {
+                    if (optional.isPresent() && pre.isEmpty()) {
                         throw new IllegalArgumentException("optional component"
                             + " must be preceded by a pre-release component"
                             + " or '+': '" + s + "'");
@@ -1353,11 +1352,11 @@ public class Runtime {
 
         private int comparePre(Version obj) {
             Optional<String> oPre = obj.pre();
-            if (!pre.isPresent()) {
+            if (pre.isEmpty()) {
                 if (oPre.isPresent())
                     return 1;
             } else {
-                if (!oPre.isPresent())
+                if (oPre.isEmpty())
                     return -1;
                 String val = pre.get();
                 String oVal = oPre.get();
@@ -1388,11 +1387,11 @@ public class Runtime {
 
         private int compareOptional(Version obj) {
             Optional<String> oOpt = obj.optional();
-            if (!optional.isPresent()) {
+            if (optional.isEmpty()) {
                 if (oOpt.isPresent())
                     return -1;
             } else {
-                if (!oOpt.isPresent())
+                if (oOpt.isEmpty())
                     return 1;
                 return optional.get().compareTo(oOpt.get());
             }

src/java.base/share/classes/java/lang/invoke/MethodHandles.java

@@ -6780,7 +6780,7 @@ assertEquals("boojum", (String) catTrace.invokeExact("boo", "jum"));
                     loopReturnType + ")");
         }
 
-        if (!pred.stream().filter(Objects::nonNull).findFirst().isPresent()) {
+        if (pred.stream().noneMatch(Objects::nonNull)) {
             throw newIllegalArgumentException("no predicate found", pred);
         }
         if (pred.stream().filter(Objects::nonNull).map(MethodHandle::type).map(MethodType::returnType).

src/java.base/share/classes/java/lang/module/Resolver.java

@@ -867,7 +867,7 @@ final class Resolver {
         Set<ModuleReference> result = new HashSet<>(beforeModules);
         for (ModuleReference mref : afterModules) {
             String name = mref.descriptor().name();
-            if (!beforeFinder.find(name).isPresent()
+            if (beforeFinder.find(name).isEmpty()
                     && findInParent(name) == null) {
                 result.add(mref);
             }

src/java.base/share/classes/java/util/Optional.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2022, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -212,7 +212,7 @@ public final class Optional<T> {
      */
     public Optional<T> filter(Predicate<? super T> predicate) {
         Objects.requireNonNull(predicate);
-        if (!isPresent()) {
+        if (isEmpty()) {
             return this;
         } else {
             return predicate.test(value) ? this : empty();
@@ -254,7 +254,7 @@ public final class Optional<T> {
      */
     public <U> Optional<U> map(Function<? super T, ? extends U> mapper) {
         Objects.requireNonNull(mapper);
-        if (!isPresent()) {
+        if (isEmpty()) {
             return empty();
         } else {
             return Optional.ofNullable(mapper.apply(value));
@@ -282,7 +282,7 @@ public final class Optional<T> {
      */
     public <U> Optional<U> flatMap(Function<? super T, ? extends Optional<? extends U>> mapper) {
         Objects.requireNonNull(mapper);
-        if (!isPresent()) {
+        if (isEmpty()) {
             return empty();
         } else {
             @SuppressWarnings("unchecked")
@@ -331,7 +331,7 @@ public final class Optional<T> {
      * @since 9
      */
     public Stream<T> stream() {
-        if (!isPresent()) {
+        if (isEmpty()) {
             return Stream.empty();
         } else {
             return Stream.of(value);