Use MessageDigest instead of HashFunction for Fingerprint

This allows us to reset and reuse the underlying digest implementation, which
guava's HashFunction doesn't allow. We do take the clone-if-possible page out
of guava's book.

--
MOS_MIGRATED_REVID=140624836

1 files changed, 11 insertions, 12 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/util/FingerprintTest.java b/src/test/java/com/google/devtools/build/lib/util/FingerprintTest.java
index 15a826482b..22e9fe79b7 100644
--- a/src/test/java/com/google/devtools/build/lib/util/FingerprintTest.java
+++ b/src/test/java/com/google/devtools/build/lib/util/FingerprintTest.java
@@ -20,14 +20,12 @@ import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.lib.vfs.inmemoryfs.InMemoryFileSystem;
-
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
 
 /**
  * Tests for Fingerprint.
@@ -56,9 +54,10 @@ public class FingerprintTest {
   // echo -n 'Hello World!'| md5sum
   @Test
   public void bytesFingerprint() {
-    assertThat("ed076287532e86365e841e92bfc50d8c").isEqualTo(
-        new Fingerprint().addBytes("Hello World!".getBytes(UTF_8)).hexDigestAndReset());
-    assertThat("ed076287532e86365e841e92bfc50d8c").isEqualTo(Fingerprint.md5Digest("Hello World!"));
+    assertThat(new Fingerprint().addBytes("Hello World!".getBytes(UTF_8)).hexDigestAndReset())
+        .isEqualTo("ed076287532e86365e841e92bfc50d8c");
+    assertThat(Fingerprint.md5Digest("Hello World!"))
+        .isEqualTo("ed076287532e86365e841e92bfc50d8c");
   }
 
   @Test
@@ -113,11 +112,11 @@ public class FingerprintTest {
   @Test
   public void addPath() throws Exception {
     PathFragment pf = new PathFragment("/etc/pwd");
-    assertThat("01cc3eeea3a2f58e447e824f9f62d3d1").isEqualTo(
-        new Fingerprint().addPath(pf).hexDigestAndReset());
+    assertThat(new Fingerprint().addPath(pf).hexDigestAndReset())
+        .isEqualTo("01cc3eeea3a2f58e447e824f9f62d3d1");
     Path p = new InMemoryFileSystem(BlazeClock.instance()).getPath(pf);
-    assertThat("01cc3eeea3a2f58e447e824f9f62d3d1").isEqualTo(
-        new Fingerprint().addPath(p).hexDigestAndReset());
+    assertThat(new Fingerprint().addPath(p).hexDigestAndReset())
+        .isEqualTo("01cc3eeea3a2f58e447e824f9f62d3d1");
   }
 
   @Test