The difference between checked exception and unchecked exception in Java

Java defines two types of exceptions:

- Checked exception: Inherit from Exception class is Checked exception. The code needs to handle the checked exception that the API throws, either with a catch statement or directly with a throws statement.

- Unchecked exception: Also known as runtimeexception, it is also inherited from exception. But all runtimeexception subclasses have a feature, that is, the code does not need to handle their exceptions can also be compiled, so they are called unchecked exception. RuntimeException (Run-time exception) does not require try...catch ... or throws mechanism to handle the exception.

The inheritance level of the nullpointerexception.

NullPointerException inherits from RuntimeException, so it is a unchecked exception.

The most commonly used five kinds of runtimeexception:

ArithmeticException	int a=0; int b= 3/a;
ClassCastException:	Object x = new Integer (0); System.out.println ((String) x);
Indexoutofboundsexception ArrayIndexOutOfBoundsException, Stringindexoutofboundsexception	int [] numbers = {1, 2, 3}; int sum = numbers[3];
IllegalArgumentException NumberFormatException	int a = Interger.parseint ("test");
Nullpointerexceptionextends

Summary:

Check exception: Do not handle compilation cannot pass

Non-inspection exception: Do not handle compilation can pass if there is thrown directly to the console.

Run-time exception: is a non-check exception

Non-run-time exception: is an inspection exception

The difference between checked exception and unchecked exception in Java