TextDevices.java

/*
Copyright (c) 2010 McDowell

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
 */
package org.apache.nifi.util.console;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;

/**
 * Convenience class for providing {@link TextDevice} implementations.
 *
 * @author McDowell
 */
public final class TextDevices {
    private TextDevices() {}

    private static TextDevice DEFAULT = (System.console() == null) ? streamDevice(
            System.in, System.out)
            : new ConsoleDevice(System.console());

    /**
     * The default system text I/O device.
     *
     * @return the default device
     */
    public static TextDevice defaultTextDevice() {
        return DEFAULT;
    }

    /**
     * Returns a text I/O device wrapping the given streams. The default system
     * encoding is used to decode/encode data.
     *
     * @param in
     *          an input source
     * @param out
     *          an output target
     * @return a new device
     */
    public static TextDevice streamDevice(InputStream in, OutputStream out) {
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));
        PrintWriter writer = new PrintWriter(out, true);
        return new CharacterDevice(reader, writer);
    }

    /**
     * Returns a text I/O device wrapping the given streams.
     *
     * @param reader
     *          an input source
     * @param writer
     *          an output target
     * @return a new device
     */
    public static TextDevice characterDevice(BufferedReader reader,
                                             PrintWriter writer) {
        return new CharacterDevice(reader, writer);
    }
}