Add @Nullable to the return declaration of methods that can clearly…

… return null. PiperOrigin-RevId: 473014878
google · Sep 8, 2022 · cde6051 · cde6051
1 parent 7962d7e
commit cde6051
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diff --git a/jimfs/src/main/java/com/google/common/jimfs/BasicAttributeProvider.java b/jimfs/src/main/java/com/google/common/jimfs/BasicAttributeProvider.java
@@ -56,6 +56,7 @@ public ImmutableSet<String> fixedAttributes() {
     return ATTRIBUTES;
   }
 
+  @NullableDecl
   @Override
   public Object get(File file, String attribute) {
     switch (attribute) {

diff --git a/jimfs/src/main/java/com/google/common/jimfs/Handler.java b/jimfs/src/main/java/com/google/common/jimfs/Handler.java
@@ -23,6 +23,7 @@
 import java.net.URL;
 import java.net.URLConnection;
 import java.net.URLStreamHandler;
+import org.checkerframework.checker.nullness.compatqual.NullableDecl;
 
 /**
  * {@link URLStreamHandler} implementation for jimfs. Named {@code Handler} so that the class can be
@@ -79,6 +80,7 @@ protected URLConnection openConnection(URL url) throws IOException {
     return new PathURLConnection(url);
   }
 
+  @NullableDecl
   @Override
   @SuppressWarnings("UnsynchronizedOverridesSynchronized") // no need to synchronize to return null
   protected InetAddress getHostAddress(URL url) {

diff --git a/jimfs/src/main/java/com/google/common/jimfs/JimfsPath.java b/jimfs/src/main/java/com/google/common/jimfs/JimfsPath.java
@@ -111,6 +111,7 @@ public boolean isAbsolute() {
     return root != null;
   }
 
+  @NullableDecl
   @Override
   public JimfsPath getRoot() {
     if (root == null) {
@@ -119,11 +120,13 @@ public JimfsPath getRoot() {
     return pathService.createRoot(root);
   }
 
+  @NullableDecl
   @Override
   public JimfsPath getFileName() {
     return names.isEmpty() ? null : getName(names.size() - 1);
   }
 
+  @NullableDecl
   @Override
   public JimfsPath getParent() {
     if (names.isEmpty() || (names.size() == 1 && root == null)) {

diff --git a/jimfs/src/main/java/com/google/common/jimfs/PathURLConnection.java b/jimfs/src/main/java/com/google/common/jimfs/PathURLConnection.java
@@ -43,6 +43,7 @@
 import java.util.Locale;
 import java.util.Map;
 import java.util.TimeZone;
+import org.checkerframework.checker.nullness.compatqual.NullableDecl;
 
 /**
  * {@code URLConnection} implementation.
@@ -133,6 +134,7 @@ public Map<String, List<String>> getHeaderFields() {
     return (ImmutableMap<String, List<String>>) (ImmutableMap<String, ?>) headers.asMap();
   }
 
+  @NullableDecl
   @Override
   public String getHeaderField(String name) {
     try {

diff --git a/jimfs/src/main/java/com/google/common/jimfs/UnixAttributeProvider.java b/jimfs/src/main/java/com/google/common/jimfs/UnixAttributeProvider.java
@@ -29,6 +29,7 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.atomic.AtomicInteger;
+import org.checkerframework.checker.nullness.compatqual.NullableDecl;
 
 /**
  * Attribute provider that provides the "unix" attribute view.
@@ -94,6 +95,7 @@ private Integer getUniqueId(Object object) {
     return id;
   }
 
+  @NullableDecl
   @SuppressWarnings("unchecked")
   @Override
   public Object get(File file, String attribute) {

diff --git a/jimfs/src/main/java/com/google/common/jimfs/UserDefinedAttributeProvider.java b/jimfs/src/main/java/com/google/common/jimfs/UserDefinedAttributeProvider.java
@@ -25,6 +25,7 @@
 import java.nio.file.attribute.FileAttributeView;
 import java.nio.file.attribute.UserDefinedFileAttributeView;
 import java.util.List;
+import org.checkerframework.checker.nullness.compatqual.NullableDecl;
 
 /**
  * Attribute provider that provides the {@link UserDefinedFileAttributeView} ("user"). Unlike most
@@ -68,6 +69,7 @@ private static ImmutableSet<String> userDefinedAttributes(File file) {
     return builder.build();
   }
 
+  @NullableDecl
   @Override
   public Object get(File file, String attribute) {
     Object value = file.getAttribute("user", attribute);