throwexception.java

Java语言是目前最流行

//抛出异常
public class ThrowException
{
	static double sqrt(double d) throws IllegalArgumentException
	{
		if(d<0)
		{
			IllegalArgumentException e = new IllegalArgumentException("不能对负数开平方");	
			throw e;			
		}
		return (Math.sqrt(d));
	}	
	public static void main(String[] aa)
	{
		System.out.println("IllegelArgumentException");
		try
		{ System.out.println(sqrt(-3)); }
		catch(IllegalArgumentException e)
		{ System.out.println(e.getMessage()); }
	}	
}