AP Computer Science A Exam Questions
and Answers
accessor method - Answer -a method that accesses an object but does not change it
actual parameter - the expression supplied for a formal parameter of a method by the caller
address - Answer -a location in memory at which a binary number (usually a byte, or value of 8 bits) is stored. The location in memory can itself be identified by a binary number - this number, the absolute or explicit address, gives the absolute location of the
address in memory, while a relative address specifies a location memory (some other address only in relation to the current, or base, address. All access to memory is access
to to a cell of memory found at a specified address.
algorithm - Answer -a well-ordered collection of unambiguous and effectively computable operations that, when executed, produces a result and halts in a finite amount of time
[[an unambiguous, executable, and terminating specification of a way to solve a problem
argument - Answer -an actual parameter in a method call, or one of the values combined by an operator]]
arithmetic/Logic Unit (ALU)
ASCII - Answer -The American Standard Code for Information Exchange - a character-
encoding scheme based on the English alphabet used to represent text in computers. It uses 8 bits to represent each character, so it is able to encode a total of 2^8 = 256 different characters. These are assigned the integer values 0 to 255. Only 32 to 126 have been assigned to printable characters. The ASCII has been largely supplanted by UNICODE and the UCS (universal character set), which are backwards compatible with it (commonly encoded using UTF-8, UTF-16, and UTF-32 representing character sets using 8, 16, and 32 bits respectively. UTF-16 can represent 65,536 characters.)
binary - Answer -the binary, or the base-2, positional numbering system represents numerical values using only two symbols, 0 and 1
bit - Answer -a contraction of binary digit; the smallest unit of information, having two possible values: 0 and 1. A data element consisting of n bits has 2ⁿ possible boolean - Answer -a data type with two possible value representing true and false.
boolean expression - Answer -an expression in a programming language that produces a boolean value when evaluated, i.e., true or false
boolean operator - Answer -an operator that can be applied to Boolean values. Java has 3 boolean, or logical, operators: &&, ||, and !.
byte - Answer -a number made up of 8 bits. Essentially, all currently manufactured computers use a byte as the smallest unit of storage in memory
cache memory - Answer -a special, super-high-speed memory unit. Operating on the principle of locality, which says that when the computer uses something it will probably use it again very soon, when the computer references a piece of data for the first time, it
stores that data in cache memory, and when it needs to fetch a piece of information, it first looks in cache memory before performing a memory fetch. Since accessing cache memory is so much faster (typically 5 to 10 times faster) than accessing RAM, it is still faster to access cache memory first and then look in RAM if the data is not found (the cache hit rate tells us just how much faster).
cast - Answer -Explicitly converting a value from one type to a different type
class - Answer -a programmer defined data type, may be a blueprint or template for creating an object
computer - Answer -the study of algorithms, including their formal and mathematical properties, their hardware realizations, their linguistic realizations, and their applications
constructor - Answer -A set of statements for initializing a newly instantiated variable
control unit - Answer -Unit within the computer that actually carries out the operations of
a program. the control unit does three things: fetches from memory the next instruction to be executed, decodes it, and executes it by issuing the appropriate command to the ALU, memory, or I/O controllers. It halts when the last instruction in the program is reached.
encapsulation - Answer -The hiding of implementation details
explicit parameter - Answer -A parameter of a method other than the object on which the method is invoked
flops - Answer -floating-point operations per second
formal parameter - Answer -a variable in a method definition; it is initialized with an actual parameter value when the method is called