michael-o commented on code in PR #203: URL: https://github.com/apache/maven-resolver/pull/203#discussion_r997978146
########## maven-resolver-util/src/main/java/org/eclipse/aether/util/FileUtils.java: ########## @@ -0,0 +1,112 @@ +package org.eclipse.aether.util; + +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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. + */ + +import java.io.IOException; +import java.nio.file.Files; +import java.nio.file.Path; +import java.nio.file.StandardCopyOption; + +import static java.util.Objects.requireNonNull; + +/** + * A utility class to write files. + * + * @since TBD + */ +public final class FileUtils +{ + private FileUtils() + { + // hide constructor + } + + /** + * A file writer, that accepts a {@link Path} to write some content to. + */ + @FunctionalInterface + public interface FileWriter + { + void write( Path path ) throws IOException; + } + + /** + * Writes file without backup. + * + * @param target that is the target file (must be file, the path must have parent). + * @param writer the writer that will accept a {@link Path} to write content to. + * @throws IOException if at any step IO problem occurs. + */ + public static void writeFile( Path target, FileWriter writer ) throws IOException + { + writeFile( target, writer, false ); + } + + /** + * Writes file with backup copy (appends ".bak" extension). + * + * @param target that is the target file (must be file, the path must have parent). + * @param writer the writer that will accept a {@link Path} to write content to. + * @throws IOException if at any step IO problem occurs. + */ + public static void writeFileWithBackup( Path target, FileWriter writer ) throws IOException + { + writeFile( target, writer, true ); + } + + /** + * Utility method to write out file to disk in "atomic" manner, with optional backups (".bak") if needed. This + * ensures that no other thread or process will be able to read not fully written files. Finally, this methos + * may create the needed parent directories, if the passed in target parents does not exist. + * + * @param target that is the target file (must be file, the path must have parent). + * @param writer the writer that will accept a {@link Path} to write content to. + * @param doBackup if {@code true}, and target file is about to be overwritten, a ".bak" file with old contents will + * be created/overwritten. + * @throws IOException if at any step IO problem occurs. + */ + private static void writeFile( Path target, FileWriter writer, boolean doBackup ) throws IOException + { + requireNonNull( target, "target is null" ); + requireNonNull( writer, "writer is null" ); + Path parent = requireNonNull( target.getParent(), "target must be a file" ); Review Comment: Ah OK, now this is clear. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@maven.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org