Remove unused Digest class.

RELNOTES: None.
PiperOrigin-RevId: 190079798

1 files changed, 0 insertions, 182 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/exec/Digest.java b/src/main/java/com/google/devtools/build/lib/exec/Digest.java
deleted file mode 100644
index ad846b4ddf..0000000000
--- a/src/main/java/com/google/devtools/build/lib/exec/Digest.java
+++ /dev/null
@@ -1,182 +0,0 @@
-// Copyright 2014 The Bazel Authors. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//    http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-package com.google.devtools.build.lib.exec;
-
-import static java.nio.charset.StandardCharsets.US_ASCII;
-
-import com.google.common.io.BaseEncoding;
-import com.google.devtools.build.lib.actions.cache.VirtualActionInput;
-import com.google.devtools.build.lib.util.Pair;
-import com.google.protobuf.ByteString;
-import com.google.protobuf.MessageLite;
-
-import java.io.IOException;
-import java.io.OutputStream;
-import java.nio.ByteBuffer;
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
-
-/**
- * A utility class for obtaining MD5 digests.
- * Digests are represented as 32 characters in lowercase ASCII.
- */
-public class Digest {
-
-  public static final ByteString EMPTY_DIGEST = fromContent(new byte[]{});
-
-  private Digest() {
-  }
-
-  /**
-   * Get the digest from the given byte array.
-   * @param bytes the byte array.
-   * @return a digest.
-   */
-  public static ByteString fromContent(byte[] bytes) {
-    MessageDigest md = newBuilder();
-    md.update(bytes, 0, bytes.length);
-    return toByteString(BaseEncoding.base16().lowerCase().encode(md.digest()));
-  }
-
-  /**
-   * Get the digest from the given ByteBuffer.
-   * @param buffer the ByteBuffer.
-   * @return a digest.
-   */
-  public static ByteString fromBuffer(ByteBuffer buffer) {
-    MessageDigest md = newBuilder();
-    md.update(buffer);
-    return toByteString(BaseEncoding.base16().lowerCase().encode(md.digest()));
-  }
-
-  /**
-   * Gets the digest of the given proto.
-   *
-   * @param proto a protocol buffer.
-   * @return the digest.
-   */
-  public static ByteString fromProto(MessageLite proto) {
-    MD5OutputStream md5Stream = new MD5OutputStream();
-    try {
-      proto.writeTo(md5Stream);
-    } catch (IOException e) {
-      throw new IllegalStateException("Unexpected IOException: ", e);
-    }
-    return toByteString(md5Stream.getDigest());
-  }
-
-  /**
-   * Gets the digest and size of a given VirtualActionInput.
-   *
-   * @param input the VirtualActionInput.
-   * @return the digest and size.
-   */
-  public static Pair<ByteString, Long> fromVirtualActionInput(VirtualActionInput input)
-      throws IOException {
-    CountingMD5OutputStream md5Stream = new CountingMD5OutputStream();
-    input.writeTo(md5Stream);
-    ByteString digest = toByteString(md5Stream.getDigest());
-    return Pair.of(digest, md5Stream.getSize());
-  }
-
-  /**
-   * A Sink that does an online MD5 calculation, which avoids forcing us to keep the entire
-   * proto message in memory.
-   */
-  private static class MD5OutputStream extends OutputStream {
-    private final MessageDigest md = newBuilder();
-
-    @Override
-    public void write(int b) {
-      md.update((byte) b);
-    }
-
-    @Override
-    public void write(byte[] b, int off, int len) {
-      md.update(b, off, len);
-    }
-
-    public String getDigest() {
-      return BaseEncoding.base16().lowerCase().encode(md.digest());
-    }
-  }
-
-  private static final class CountingMD5OutputStream extends MD5OutputStream {
-    private long size;
-
-    @Override
-    public void write(int b) {
-      super.write(b);
-      size++;
-    }
-
-    @Override
-    public void write(byte[] b, int off, int len) {
-      super.write(b, off, len);
-      size += len;
-    }
-
-    public long getSize() {
-      return size;
-    }
-  }
-
-  /**
-   * @param digest the digest to check.
-   * @return true iff digest is a syntactically legal digest. It must be 32
-   *         characters of hex with lowercase letters.
-   */
-  public static boolean isDigest(ByteString digest) {
-    if (digest == null || digest.size() != 32) {
-      return false;
-    }
-
-    for (byte b : digest) {
-      char c = (char) b;
-      if ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f')) {
-        continue;
-      }
-      return false;
-    }
-    return true;
-  }
-
-  /**
-   * @param digest the digest.
-   * @return true iff the digest is that of an empty file.
-   */
-  public static boolean isEmpty(ByteString digest) {
-    return digest.equals(EMPTY_DIGEST);
-  }
-
-  /**
-   * @return a new MD5 digest builder.
-   */
-  public static MessageDigest newBuilder() {
-    try {
-      return MessageDigest.getInstance("md5");
-    } catch (NoSuchAlgorithmException e) {
-      throw new IllegalStateException("MD5 not available", e);
-    }
-  }
-
-  /**
-   * Convert a String digest into a ByteString using ascii.
-   * @param digest the digest in ascii.
-   * @return the digest as a ByteString.
-   */
-  public static ByteString toByteString(String digest) {
-    return ByteString.copyFrom(digest.getBytes(US_ASCII));
-  }
-}