java位操作应用一则

这里我写了一个基类, 来对选项进行位操作.
采用位来作为判断是否包含某个选项, 而所有的选项常量都采用"1<<n"来定义, 即2的n次方

public abstract class BaseOption {

	public long options; // 选项合集

	/**
	 * 添加选项
	 * 
	 * @param option
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public <T extends BaseOption> T add(long option) {
		if ((option & (option - 1)) != 0) {
			throw new IllegalArgumentException("option必须为2的n次方");
		}
		this.options = this.options | option;
		return (T) this;
	}

	/**
	 * 删除选项
	 * 
	 * @param <T>
	 * @param option
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public <T extends BaseOption> T remove(int option) {
		if ((option & (option - 1)) != 0) {
			throw new IllegalArgumentException("option必须为2的n次方");
		}
		options = this.options & (option ^ Long.MAX_VALUE);
		return (T) this;
	}

	/**
	 * 是否包含选项
	 * 
	 * @param option
	 * @return
	 */
	public boolean contains(long option) {
		return ((this.options & option) == option);
	}

	public static void main(String[] args) {
		BaseOption co = new BaseOption() {};
		co.options = 2;
		co.add(2);
		Assert.assertEquals(2, co.options);
		co.options = 4;
		co.add(2);
		Assert.assertEquals(6, co.options);
		co.add(1);
		Assert.assertEquals(7, co.options);
		co.add(1);
		Assert.assertEquals(7, co.options);
		co.add(0);
		Assert.assertEquals(7, co.options);
		try {
			co.add(6);
			Assert.fail();
		}catch (Exception e) {
		}
		co.remove(1);
		Assert.assertEquals(6, co.options);
		co.remove(2);
		Assert.assertEquals(4, co.options);
		co.remove(4);
		try {
			co.remove(6);
			Assert.fail();
		}catch (Exception e) {
		}
		Assert.assertEquals(0, co.options);
		co.remove(4);
		Assert.assertEquals(0, co.options);
		System.out.println("test is successful!");
	}
}