1 files changed, 84 insertions, 74 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/FileArtifactValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/FileArtifactValue.java
index cfdcb187de..2f06471ce4 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/FileArtifactValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/FileArtifactValue.java
@@ -17,6 +17,9 @@ import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.MoreObjects;
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.actions.cache.DigestUtils;
+import com.google.devtools.build.lib.actions.cache.Metadata;
+import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
+import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
 import com.google.devtools.build.lib.util.Preconditions;
 import com.google.devtools.build.lib.vfs.FileStatus;
 import com.google.devtools.build.lib.vfs.Path;
@@ -39,8 +42,9 @@ import javax.annotation.Nullable;
  * </ul>
  */
 // TODO(janakr): make this an interface once JDK8 allows us to have static methods on interfaces.
-public abstract class FileArtifactValue implements SkyValue {
-  private static final class SingletonMarkerValue extends FileArtifactValue {
+@Immutable @ThreadSafe
+public abstract class FileArtifactValue implements SkyValue, Metadata {
+  private static final class SingletonMarkerValue extends FileArtifactValue implements Singleton {
     @Nullable
     @Override
     public byte[] getDigest() {
@@ -48,7 +52,7 @@ public abstract class FileArtifactValue implements SkyValue {
     }
 
     @Override
-    boolean isFile() {
+    public boolean isFile() {
       return false;
     }
 
@@ -68,6 +72,33 @@ public abstract class FileArtifactValue implements SkyValue {
     }
   }
 
+  private static final class OmittedFileValue extends FileArtifactValue implements Singleton {
+    @Override
+    public byte[] getDigest() {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean isFile() {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public long getSize() {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public long getModifiedTime() {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public String toString() {
+      return "OMITTED_FILE_MARKER";
+    }
+  }
+
   static final FileArtifactValue DEFAULT_MIDDLEMAN = new SingletonMarkerValue();
   /** Data that marks that a file is not present on the filesystem. */
   @VisibleForTesting
@@ -77,33 +108,7 @@ public abstract class FileArtifactValue implements SkyValue {
    * Represents an omitted file -- we are aware of it but it doesn't exist. All access methods are
    * unsupported.
    */
-  static final FileArtifactValue OMITTED_FILE_MARKER =
-      new FileArtifactValue() {
-        @Override
-        public byte[] getDigest() {
-          throw new UnsupportedOperationException();
-        }
-
-        @Override
-        boolean isFile() {
-          throw new UnsupportedOperationException();
-        }
-
-        @Override
-        public long getSize() {
-          throw new UnsupportedOperationException();
-        }
-
-        @Override
-        public long getModifiedTime() {
-          throw new UnsupportedOperationException();
-        }
-
-        @Override
-        public String toString() {
-          return "OMITTED_FILE_MARKER";
-        }
-      };
+  static final FileArtifactValue OMITTED_FILE_MARKER = new OmittedFileValue();
 
   private static final class DirectoryArtifactValue extends FileArtifactValue {
     private final long mtime;
@@ -134,18 +139,6 @@ public abstract class FileArtifactValue implements SkyValue {
     }
 
     @Override
-    public int hashCode() {
-      return (int) mtime;
-    }
-
-    @Override
-    public boolean equals(Object other) {
-      return (this == other)
-          || ((other instanceof DirectoryArtifactValue)
-              && this.mtime == ((DirectoryArtifactValue) other).mtime);
-    }
-
-    @Override
     public String toString() {
       return MoreObjects.toStringHelper(this).add("mtime", mtime).toString();
     }
@@ -166,7 +159,7 @@ public abstract class FileArtifactValue implements SkyValue {
     }
 
     @Override
-    boolean isFile() {
+    public boolean isFile() {
       return true;
     }
 
@@ -182,29 +175,6 @@ public abstract class FileArtifactValue implements SkyValue {
     }
 
     @Override
-    public int hashCode() {
-      // Hash digest by content, not reference.
-      return 37 * (int) size + Arrays.hashCode(digest);
-    }
-
-    /**
-     * Two RegularFileArtifactValues will only compare equal if they have the same content. This
-     * differs from the {@code Metadata#equivalence} method, which allows for comparison using mtime
-     * if one object does not have a digest available.
-     */
-    @Override
-    public boolean equals(Object other) {
-      if (this == other) {
-        return true;
-      }
-      if (!(other instanceof RegularFileArtifactValue)) {
-        return false;
-      }
-      RegularFileArtifactValue that = (RegularFileArtifactValue) other;
-      return this.size == that.size && Arrays.equals(this.digest, that.digest);
-    }
-
-    @Override
     public String toString() {
       return MoreObjects.toStringHelper(this).add("digest", digest).add("size", size).toString();
     }
@@ -239,10 +209,18 @@ public abstract class FileArtifactValue implements SkyValue {
     return createNormalFile(digest, size);
   }
 
-  static FileArtifactValue createNormalFile(byte[] digest, long size) {
+  public static FileArtifactValue createNormalFile(byte[] digest, long size) {
     return new RegularFileArtifactValue(digest, size);
   }
 
+  static FileArtifactValue createNormalFile(FileValue fileValue) {
+    return new RegularFileArtifactValue(fileValue.getDigest(), fileValue.getSize());
+  }
+
+  public static FileArtifactValue createDirectory(long mtime) {
+    return new DirectoryArtifactValue(mtime);
+  }
+
   /**
    * Creates a FileArtifactValue used as a 'proxy' input for other ArtifactValues.
    * These are used in {@link com.google.devtools.build.lib.actions.ActionCacheChecker}.
@@ -252,16 +230,48 @@ public abstract class FileArtifactValue implements SkyValue {
     return createNormalFile(digest, /*size=*/ 0);
   }
 
-  /** Returns the digest of this value. Null for non-files, non-null for files. */
+  @Override
+  public abstract boolean isFile();
+
   @Nullable
+  @Override
   public abstract byte[] getDigest();
 
-  /** @return true if this is a file or a symlink to an existing file */
-  abstract boolean isFile();
-
-  /** Gets the size of the file. Non-files (including directories) have size 0. */
+  @Override
   public abstract long getSize();
 
-  /** Gets last modified time of file. Should only be called if this is not a file. */
-  abstract long getModifiedTime();
+  @Override
+  public abstract long getModifiedTime();
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (!(o instanceof Metadata)) {
+      return false;
+    }
+    if ((this instanceof Singleton) || (o instanceof Singleton)) {
+      return false;
+    }
+    Metadata m = (Metadata) o;
+    if (isFile()) {
+      return m.isFile() && Arrays.equals(getDigest(), m.getDigest()) && getSize() == m.getSize();
+    } else {
+      return !m.isFile() && getModifiedTime() == m.getModifiedTime();
+    }
+  }
+
+  @Override
+  public int hashCode() {
+    if (this instanceof Singleton) {
+      return System.identityHashCode(this);
+    }
+    // Hash digest by content, not reference.
+    if (isFile()) {
+      return 37 * Long.hashCode(getSize()) + Arrays.hashCode(getDigest());
+    } else {
+      return Long.hashCode(getModifiedTime());
+    }
+  }
 }