General-purpose StringConverter class that utilizes generics in Java8

	private static class StringConverter<T> {

		private static final List<StringConverter<?>> converters = Arrays.asList(
				new StringConverter<>(String.class, String::toString),
				new StringConverter<>(BigDecimal.class, BigDecimal::toPlainString),
				new StringConverter<>(Date.class, Date::toString)
		);

		private final Class<T> clazz;
		private final Function<T, String> converter;

		static String convert(final Object object) {
			if(object == null){
				return null;
			}
			return converters.stream().filter(c -> c.isApplicable(object)).map(c -> c.doConvert(object)).findFirst()
					.orElseThrow(() -> new IllegalArgumentException("Unexpected class:" + object.getClass().getName()));
		}

		private StringConverter(final Class<T> clazz, final Function<T, String> converter) {
			this.clazz = clazz;
			this.converter = converter;
		}

		private boolean isApplicable(final Object object) {
			return clazz.isInstance(object);
		}

		private String doConvert(final Object object) {
			return converter.apply(clazz.cast(object));
		}

	}

String hoge = StringConverter<The class you want to convert(Please define it in converters)>.convert(obj);

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