MavenWrapperDownloader.java

/*
 * 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.io.InputStream;
import java.net.Authenticator;
import java.net.PasswordAuthentication;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;

public final class MavenWrapperDownloader {
	private static final String WRAPPER_VERSION = "3.2.0";

	private static final boolean VERBOSE = Boolean.parseBoolean( System.getenv( "MVNW_VERBOSE" ) );

	public static void main(String[] args) {
		log( "Apache Maven Wrapper Downloader " + WRAPPER_VERSION );

		if ( args.length != 2 ) {
			System.err.println( " - ERROR wrapperUrl or wrapperJarPath parameter missing" );
			System.exit( 1 );
		}

		try {
			log( " - Downloader started" );
			final URL wrapperUrl = new URL( args[0] );
			final String jarPath = args[1].replace( "..", "" ); // Sanitize path
			final Path wrapperJarPath = Paths.get( jarPath ).toAbsolutePath().normalize();
			downloadFileFromURL( wrapperUrl, wrapperJarPath );
			log( "Done" );
		}
		catch (IOException e) {
			System.err.println( "- Error downloading: " + e.getMessage() );
			if ( VERBOSE ) {
				e.printStackTrace();
			}
			System.exit( 1 );
		}
	}

	private static void downloadFileFromURL(URL wrapperUrl, Path wrapperJarPath)
			throws IOException {
		log( " - Downloading to: " + wrapperJarPath );
		if ( System.getenv( "MVNW_USERNAME" ) != null && System.getenv( "MVNW_PASSWORD" ) != null ) {
			final String username = System.getenv( "MVNW_USERNAME" );
			final char[] password = System.getenv( "MVNW_PASSWORD" ).toCharArray();
			Authenticator.setDefault( new Authenticator() {
				@Override
				protected PasswordAuthentication getPasswordAuthentication() {
					return new PasswordAuthentication( username, password );
				}
			} );
		}
		try ( InputStream inStream = wrapperUrl.openStream() ) {
			Files.copy( inStream, wrapperJarPath, StandardCopyOption.REPLACE_EXISTING );
		}
		log( " - Downloader complete" );
	}

	private static void log(String msg) {
		if ( VERBOSE ) {
			System.out.println( msg );
		}
	}

}