diff options
Diffstat (limited to 'java/com/google/devtools/build/android/desugar/io/ZipOutputFileProvider.java')
-rw-r--r-- | java/com/google/devtools/build/android/desugar/io/ZipOutputFileProvider.java | 78 |
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(); + } +} |