1 files changed, 78 insertions, 0 deletions
diff --git a/java/com/google/devtools/build/android/desugar/io/ZipOutputFileProvider.java b/java/com/google/devtools/build/android/desugar/io/ZipOutputFileProvider.java
new file mode 100644
index 0000000..36cb26d
--- /dev/null
+++ b/java/com/google/devtools/build/android/desugar/io/ZipOutputFileProvider.java
@@ -0,0 +1,78 @@
+// Copyright 2017 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.android.desugar.io;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.common.io.ByteStreams;
+import java.io.BufferedOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.zip.CRC32;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipOutputStream;
+
+/** Output provider is a zip file. */
+class ZipOutputFileProvider implements OutputFileProvider {
+
+  private final ZipOutputStream out;
+
+  public ZipOutputFileProvider(Path root) throws IOException {
+    out = new ZipOutputStream(new BufferedOutputStream(Files.newOutputStream(root)));
+  }
+
+  @Override
+  public void copyFrom(String filename, InputFileProvider inputFileProvider) throws IOException {
+    // TODO(bazel-team): Avoid de- and re-compressing resource files
+    out.putNextEntry(inputFileProvider.getZipEntry(filename));
+    try (InputStream is = inputFileProvider.getInputStream(filename)) {
+      ByteStreams.copy(is, out);
+    }
+    out.closeEntry();
+  }
+
+  @Override
+  public void write(String filename, byte[] content) throws IOException {
+    checkArgument(filename.equals(DESUGAR_DEPS_FILENAME) || filename.endsWith(".class"),
+        "Expect file to be copied: %s", filename);
+    writeStoredEntry(out, filename, content);
+  }
+
+  @Override
+  public void close() throws IOException {
+    out.close();
+  }
+
+  private static void writeStoredEntry(ZipOutputStream out, String filename, byte[] content)
+      throws IOException {
+    // Need to pre-compute checksum for STORED (uncompressed) entries)
+    CRC32 checksum = new CRC32();
+    checksum.update(content);
+
+    ZipEntry result = new ZipEntry(filename);
+    result.setTime(0L); // Use stable timestamp Jan 1 1980
+    result.setCrc(checksum.getValue());
+    result.setSize(content.length);
+    result.setCompressedSize(content.length);
+    // Write uncompressed, since this is just an intermediary artifact that
+    // we will convert to .dex
+    result.setMethod(ZipEntry.STORED);
+
+    out.putNextEntry(result);
+    out.write(content);
+    out.closeEntry();
+  }
+}