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programmer-created exception class comparison table

Subject	have syntax rule	receive	model	add	declare	protect	wait on	is a subtopic of	create you	create by	name after	access	refer to	see also		extend	notify	has part	provide	place in	represent	inherit	contain	have example	instantiate you	send	implement	convert into	import from	order	is a kind of	share	be a descendant of	define	specify by	convert	have access modifier	refer to by	hide	have example of creation	use	override	have syntax	have benefit	be a member of	have	have part	return	has definition	throw when	be	communicate with	is partitioned into
class	bold = mandatory italic = non-terminal normal font = optional			0 or more methods to the methods it inherits from its superclass	a list of variables, called instance variables, corresponding to data that will be present in each instance	its members from access by other classes or objects using an access modifier		Classes			the internals of a computer system such as 'Record', 'Table', 'Data', 'Structure', or 'Information'	any public class in other packages			if a class is not declared public then it is accessible only to members of the same package	only one superclass			implementation for all its instance methods unless the class is abstract	its own source file	several similar objects	behaviour from its superclass	data associated with each object	public class HelloWorld { public static void main(String[] args) { System.out.println("Hello World!"); } }	create an instance of it		more than one interface		a package	elements as follows: class variables instance variables constructors the most important public methods methods that are simply used to access variables private methods	specification		Object class	a class type whose instances are the values of the class type	1 class definition		public or private or protected				an implements clause to declare that it contains methods for each of the operations specified by the interface	methods that are inherited from the class's superclass	class classname { // declarations of variables // declarations of constructors // declarations of other methods with public ones first }	reusability modularity	1 named package rather than the default package	a unique name since somebody in the future might want to import the packages containing both classes and hence create a name clash	constructor		A template that describes the data and behaviour of its instances called objects		the unit of data abstraction in an object-oriented program		abstract class, concrete class
exception		messages from objects in the same process objects in different processes objects on the same machine objects on different machines	a real-world object or an abstract concept				0 or more condition variables	Exception Handling	use the new operator	declaring and initializing it such that it is created whenever execution enters a particular block, or, in the case of an instance variable, when an instance is created, for example: String aString = "some text"; or by declaring it and initializing it later using the new operator, for example: String aString; aString = new String("some text");		all instance variables of all objects of its class	without reference to the instance variables contained in it	Exception class	if an exception is raised in a statement that is not in a try block with an appropriate catch statement then Java looks to see if the caller of the current method is within a try block that has an appropriate catch block if this is not successful, Java looks at callers right up to the main program otherwise Java reports an error if it has not been able to find any suitable catch block		other objects that a condition variable has changed	public interface			any entity to which you can associate properties and behaviour	instance methods and instance variables from the class to which it belongs all that class's superclasses				messages to objects in the same process objects in different processes objects on the same machine objects on different machines		a string using the toString method			object	one copy of each class variable of its class with the other instances of its class				itself to a string representation using the toString method		several different variables at the same time	methods from other objects using the 'private' keyword	String name = new String();						state that is maintained in its variables		its class using the getClass method	An event that happens during program execution that prevents the program from continuing normally; generally, an error	something goes wrong in the execution of a program	distinct from every other object even if they contain the same data	other objects by sending and receiving messages	unchecked exception, checked exception
programmer-created exception class	bold = mandatory italic = non-terminal normal font = optional	messages from objects in the same process objects in different processes objects on the same machine objects on different machines	a real-world object or an abstract concept	0 or more methods to the methods it inherits from its superclass	a list of variables, called instance variables, corresponding to data that will be present in each instance	its members from access by other classes or objects using an access modifier	0 or more condition variables	Exception Handling	use the new operator	declaring and initializing it such that it is created whenever execution enters a particular block, or, in the case of an instance variable, when an instance is created, for example: String aString = "some text"; or by declaring it and initializing it later using the new operator, for example: String aString; aString = new String("some text");	the internals of a computer system such as 'Record', 'Table', 'Data', 'Structure', or 'Information'	any public class in other packages	without reference to the instance variables contained in it	Exception class	if an exception is raised in a statement that is not in a try block with an appropriate catch statement then Java looks to see if the caller of the current method is within a try block that has an appropriate catch block if this is not successful, Java looks at callers right up to the main program otherwise Java reports an error if it has not been able to find any suitable catch block	only one superclass	other objects that a condition variable has changed	public interface	implementation for all its instance methods unless the class is abstract	its own source file	several similar objects	behaviour from its superclass	data associated with each object	public class HelloWorld { public static void main(String[] args) { System.out.println("Hello World!"); } }	create an instance of it	messages to objects in the same process objects in different processes objects on the same machine objects on different machines	more than one interface	a string using the toString method	a package	elements as follows: class variables instance variables constructors the most important public methods methods that are simply used to access variables private methods	exception	one copy of each class variable of its class with the other instances of its class	Object class	a class type whose instances are the values of the class type	1 class definition	itself to a string representation using the toString method	public or private or protected	several different variables at the same time	methods from other objects using the 'private' keyword	String name = new String();	an implements clause to declare that it contains methods for each of the operations specified by the interface	methods that are inherited from the class's superclass	class classname { // declarations of variables // declarations of constructors // declarations of other methods with public ones first }	reusability modularity	1 named package rather than the default package	a unique name since somebody in the future might want to import the packages containing both classes and hence create a name clash	constructor	its class using the getClass method		something goes wrong in the execution of a program	the unit of data abstraction in an object-oriented program	other objects by sending and receiving messages

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