ManifestStripper.java

/*
 * 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 io.github.zlika.reproducible;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.nio.charset.StandardCharsets;

/**
 * Strips non-reproducible data from MANIFEST files.
 * This stripper removes the following lines from the manifest:
 * - Built-By
 * - Created-By
 * - Build-Jdk
 * - Build-Date / Build-Time
 * - Bnd-LastModified
 */
final class ManifestStripper implements Stripper
{
    @Override
    public void strip(File in, File out) throws IOException
    {
        try (final BufferedWriter writer = new BufferedWriter(
                    new OutputStreamWriter(new FileOutputStream(out), StandardCharsets.UTF_8));
             final BufferedReader reader = new BufferedReader(
                    new InputStreamReader(new FileInputStream(in), StandardCharsets.UTF_8)))
        {
            reader.lines().filter(s -> !s.startsWith("Built-By"))
                        .filter(s -> !s.startsWith("Created-By"))
                        .filter(s -> !s.startsWith("Build-Jdk"))
                        .filter(s -> !s.startsWith("Build-Date"))
                        .filter(s -> !s.startsWith("Build-Time"))
                        .filter(s -> !s.startsWith("Bnd-LastModified"))
                        .forEach(s -> 
                        {
                            try
                            {
                                writer.write(s);
                                writer.write("\r\n");
                            }
                            catch (IOException e)
                            {
                            }
                        });
        }
    }
}