Throw:

1, Acting in the method body , Indicates that a specific exception is thrown , Handled by statements inside the method

2, Specific outward throwing action , So what it throws is an exception entity class . If you execute throw It must have thrown some specific exception object

3,Throw The exception thrown means that such an exception must occur .

public static void testThrow(Integer n) {
		if (n == null) {
			throw new NullPointerException();// Runtime exceptions do not need to be declared on methods 
		}
	}

Throws:

1, Acts on the declaration of a method , If an exception is thrown , The caller of this method will handle the exception .

2, The main statement is that this method will throw some kind of exception , Let its users know the type of exception caught

3,Throws The exception thrown may happen , But it doesn't necessarily happen .

public static byte[] toGBK(String s) throws UnsupportedEncodingException {
		return s.getBytes("GBK");
	}