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A replacement for java.io.Console with a System.in and System.out based fallback
The newest version!
/*
 * SPDX-FileCopyrightText: 2018 Marc Nause 
 *
 * SPDX-License-Identifier: Apache-2.0
 */

package de.audioattack.io;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Reader;
import java.util.Objects;

/**
 * Console which is based on provided readers and writers.
 */
public class CharacterDevice implements Console {

    private final BufferedReader reader;

    private final PrintWriter writer;

    /**
     * Constructor.
     *
     * @param reader used to read characters, must not be {@code null}
     * @param writer used to write characters, must not be {@code null}
     */
    CharacterDevice(final BufferedReader reader, final PrintWriter writer) {
        this.reader = Objects.requireNonNull(reader, "reader must not be ");
        this.writer = Objects.requireNonNull(writer, "writer must not be ");
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public Reader reader() {
        return new UncloseableReader(reader);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public PrintWriter writer() {
        return new UncloseablePrintWriter(writer);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public Console format(final String fmt, final Object... args) {
        writer.format(fmt, args);
        flush();
        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public Console printf(final String fmt, final Object... args) {
        return format(fmt, args);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String readLine(final String fmt, final Object... args) {
        format(fmt, args);
        return readLine();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String readLine() {
        try {
            return reader.readLine();
        } catch (final IOException e) {
            return null;
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public char[] readPassword(final String fmt, final Object... args) {
        format("WARNING! Password will be visible in the command line!%n");
        return toCharArray(readLine(fmt, args));
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public char[] readPassword() {
        return readPassword("");
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void flush() {
        writer.flush();
    }

    private static char[] toCharArray(final String readLine) {
        return readLine == null ? null : readLine.toCharArray();
    }
}