Difference Between Throw and Throws in Java?

Question

Is it possible to clearly indicate the difference between the throw and the throws in Java exception handling with an example? I tried google search but could not come to a conclusion. Pls Help

Answer 1

• throws used to declare an exception, and the throw keyword is used to explicitly throw an exception.

• If we see the wise syntax, then throw followed by an instance variable, and throws followed by the names of the exception classes.

• The throw keyword is used inside the method body to throw exception, and the throws used in the method declaration (signature).

for instance

throw

 throw new Exception("You have some exception") throw new IOException("Connection failed!!") 

throws

 public int myMethod() throws IOException, ArithmeticException, NullPointerException {} 

4. You cannot throw multiple exceptions with throw . You can declare a few exceptions, for example. public void method () throws an IOException, SQLException.

5. checked exceptions cannot be propagated using throw just because it is explicitly used to throw a specific exception. checked exception can be thrown using throws .

Propagation of exceptions: An exception propagates from method to method, to the call stack, until it is caught. Therefore, if a () calls b (), which calls c (), which calls d (), and if d () throws an exception, the exception will propagate from d to c to b to a, unless only one of these methods will catch the exception. What is exception propagation?

Answer 2

use throw to throw the actual Exception and throws declare by the method that it can throw Exception .

 public int findMax(int[] array) throws Exception{ if(array==null) throw new NullPointerException(...); ... } 

Answer 3

 public void someMethod(List<Foo> someList) throws SomeException { if (someList.isEmpty()) throw new SomeException(); }