String Switch

gistfile1.txt

package de.michaelwellner.edu.stringswitch;

public class StringSwitch {

  private static final String HALLO = "Hallo";
	private static final String GUT = "Gut";
	private static final String SCHOENEN_TAG = "Schönen Tag noch!";
	private static final String CIAO = "Ciao";
	private static final String TSCHUESS = "Tschüss";

	private static final String HALLO_WIE = "Hallo, wie geht es dir?";
	private static final String PRIMA = "Das finde ich prima!";
	private static final String DANKE = "Danke dir auch!";
	private static final String BIS_BALD = "Bis bald!";
	private static final String NOPE = "Leider habe ich dich nicht verstanden.";

	private static final Console C = new Console();

	private static interface Output {

		public void println(String s);

	}

	private static class Console implements Output {

		@Override
		public void println(String s) {
			System.out.println(s);
		}

	}

	private static class Kummerkasten implements Output {

		@Override
		public void println(String s) {
			// Und ab nach /dev/null ...
		}

	}

	public StringSwitch(final String... args) {
		for (int i = 0; i < 10; test(i++));
	}

	private void test(int num, final String ... args) {
		C.println("Testlauf " + num);
		
		long j6 = benchmark(new Runnable() {

			@Override
			public void run() {
				java6(new Kummerkasten(), args);
			}

		});
		
		C.println("Java 6: " + j6);

		long j7 = benchmark(new Runnable() {

			@Override
			public void run() {
				java7(new Kummerkasten(), args);
			}

		});
		
		C.println("Java 7: " + j7);
		
		C.println("Diff:   " + (j7 - j6));
		
		C.println("");
	}

	private long benchmark(Runnable runnable) {
		long start = System.currentTimeMillis();
		for (long i = 0; i < 500_000_000; i++) {
			runnable.run();
		}
		long end = System.currentTimeMillis();
		return end - start;
	}

	private void java7(Output out, String... args) {
		for (String arg : args) {
			switch (arg) {
			case HALLO:
				out.println(HALLO_WIE);
				break;
			case GUT:
				out.println(PRIMA);
				break;
			case SCHOENEN_TAG:
				out.println(DANKE);
			case CIAO:
			case TSCHUESS:
				out.println(BIS_BALD);
				break;
			default:
				out.println(NOPE);
			}
		}
	}

	private void java6(Output out, String... args) {
		for (String arg : args) {
			if (arg.equals(HALLO)) {
				out.println(HALLO_WIE);
			} else if (arg.equals(GUT)) {
				out.println(PRIMA);
			} else if (arg.equals(SCHOENEN_TAG)) {
				out.println(DANKE);
				out.println(BIS_BALD);
			} else if (arg.equals(CIAO) || arg.equals(TSCHUESS)) {
				out.println(BIS_BALD);
			} else {
				out.println(NOPE);
			}
		}
	}

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		new StringSwitch(HALLO, GUT, CIAO);
	}

}