Unzip.java

/*
 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
 *
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 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
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/*
 * This source code is provided to illustrate the usage of a given feature
 * or technique and has been deliberately simplified. Additional steps
 * required for a production-quality application, such as security checks,
 * input validation, and proper error handling, might not be present in
 * this sample code.
 */

import java.io.IOException;
import java.io.UncheckedIOException;
import java.nio.file.*;

import static java.nio.file.StandardCopyOption.REPLACE_EXISTING;

/**
 * Extract (unzip) a file to the current directory.
 */
public class Unzip {

    /**
     * The main method for the Unzip program. Run the program with an empty
     * argument list to see possible arguments.
     *
     * @param args the argument list for {@code Unzip}.
     */
    public static void main(String[] args) {
        if (args.length != 1) {
            System.out.println("Usage: Unzip zipfile");
        }
        final Path destDir = Paths.get(".");
        /*
         * Create AutoCloseable FileSystem. It will be closed automatically
         * after the try block.
         */
        try (FileSystem zipFileSystem = FileSystems.newFileSystem(Paths.get(args[0]), null)) {

            Path top = zipFileSystem.getPath("/");
            Files.walk(top).skip(1).forEach(file -> {
                Path target = destDir.resolve(top.relativize(file).toString());
                System.out.println("Extracting " + target);
                try {
                    Files.copy(file, target, REPLACE_EXISTING);
                } catch (IOException e) {
                    throw new UncheckedIOException(e);
                }
            });
        } catch (UncheckedIOException | IOException e) {
            e.printStackTrace();
            System.exit(1);
        }
    }
}