8298380: Clean up redundant array length checks in JDK code base

Reviewed-by: dholmes, amenkov, serb, vtewari

src/java.base/linux/classes/sun/nio/fs/LinuxWatchService.java

@@ -226,8 +226,7 @@ class LinuxWatchService
             }
 
             // no modifiers supported at this time
-            if (modifiers.length > 0) {
+            for (WatchEvent.Modifier modifier : modifiers) {
-                for (WatchEvent.Modifier modifier: modifiers) {
                 if (modifier == null)
                     return new NullPointerException();
                 if (!ExtendedOptions.SENSITIVITY_HIGH.matches(modifier) &&
@@ -236,7 +235,6 @@ class LinuxWatchService
                     return new UnsupportedOperationException("Modifier not supported");
                 }
             }
-            }
 
             // check file is directory
             UnixFileAttributes attrs = null;

src/java.base/share/classes/java/nio/file/spi/FileSystemProvider.java

@@ -411,14 +411,12 @@ public abstract class FileSystemProvider {
     public InputStream newInputStream(Path path, OpenOption... options)
         throws IOException
     {
-        if (options.length > 0) {
+        for (OpenOption opt : options) {
-            for (OpenOption opt: options) {
             // All OpenOption values except for APPEND and WRITE are allowed
             if (opt == StandardOpenOption.APPEND ||
                 opt == StandardOpenOption.WRITE)
                 throw new UnsupportedOperationException("'" + opt + "' not allowed");
         }
-        }
         ReadableByteChannel rbc = Files.newByteChannel(path, options);
         if (rbc instanceof FileChannelImpl) {
             ((FileChannelImpl) rbc).setUninterruptible();

src/java.base/share/classes/jdk/internal/jrtfs/JrtPath.java

@@ -627,13 +627,11 @@ final class JrtPath implements Path {
     }
 
     final InputStream newInputStream(OpenOption... options) throws IOException {
-        if (options.length > 0) {
         for (OpenOption opt : options) {
             if (opt != READ) {
                 throw new UnsupportedOperationException("'" + opt + "' not allowed");
             }
         }
-        }
         return jrtfs.newInputStream(this);
     }
 

src/java.base/share/classes/sun/nio/fs/PollingWatchService.java

@@ -119,8 +119,7 @@ class PollingWatchService
 
         // Extended modifiers may be used to specify the sensitivity level
         int sensitivity = DEFAULT_POLLING_INTERVAL;
-        if (modifiers.length > 0) {
+        for (WatchEvent.Modifier modifier : modifiers) {
-            for (WatchEvent.Modifier modifier: modifiers) {
             if (modifier == null)
                 throw new NullPointerException();
 
@@ -134,7 +133,6 @@ class PollingWatchService
                 throw new UnsupportedOperationException("Modifier not supported");
             }
         }
-        }
 
         // check if watch service is closed
         if (!isOpen())

src/java.desktop/macosx/classes/com/apple/laf/AquaFileChooserUI.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 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
@@ -653,10 +653,8 @@ public class AquaFileChooserUI extends FileChooserUI {
                 int selectableCount = 0;
                 // Double-check that all the list selections are valid for this mode
                 // Directories can be selected in the list regardless of mode
-                if (rows.length > 0) {
                 for (final int element : rows) {
-                        if (isSelectableForMode(chooser, (File)fFileList.getValueAt(element, 0))) selectableCount++;
+                    if (isSelectableForMode(chooser, (File) fFileList.getValueAt(element, 0))) selectableCount++;
-                    }
                 }
                 if (selectableCount > 0) {
                     final File[] files = new File[selectableCount];

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.meta/src/jdk/vm/ci/meta/Assumptions.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 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
@@ -89,12 +89,10 @@ public final class Assumptions implements Iterable<Assumptions.Assumption> {
         public void recordTo(Assumptions target) {
             assert canRecordTo(target);
 
-            if (assumptions.length > 0) {
             for (Assumption assumption : assumptions) {
                 target.record(assumption);
             }
         }
-        }
 
         @Override
         public String toString() {

src/jdk.jconsole/share/classes/sun/tools/jconsole/inspector/XTree.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 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
@@ -649,7 +649,7 @@ public class XTree extends JTree {
                         Messages.NOTIFICATIONS, null);
                 notifications.setUserObject(notificationsUO);
                 node.insert(notifications, childIndex++);
-                if (ni != null && ni.length > 0) {
+                if (ni != null) {
                     for (MBeanNotificationInfo mbni : ni) {
                         DefaultMutableTreeNode notification =
                                 new DefaultMutableTreeNode();

src/jdk.zipfs/share/classes/jdk/nio/zipfs/ZipPath.java

@@ -744,12 +744,10 @@ final class ZipPath implements Path {
 
     InputStream newInputStream(OpenOption... options) throws IOException
     {
-        if (options.length > 0) {
         for (OpenOption opt : options) {
             if (opt != READ)
                 throw new UnsupportedOperationException("'" + opt + "' not allowed");
         }
-        }
         return zfs.newInputStream(getResolvedPath());
     }