AP Computer Science A study guide
AP Computer Science A · Work through your exam, one topic at a time.
AP Computer Science A is an Advanced Placement course and exam administered by the College Board. It is designed as the equivalent of "A one-semester, introductory college course in computer science," and it is aimed at high school students who want to design, write, and test programs in a subset of the Java programming language. The course framework emphasizes analyzing, writing, and testing code while exploring modularity, variables, and control structures, and it develops skills in designing programs, correcting errors, and documenting how code works. Content is organized into four commonly taught units: Using Objects and Methods, Selection and Iteration, Class Creation, and Data Collections. The AP Computer Science A study guide has 4 sections and about 1,190 words.
01Using Objects and Methods
Every AP CSA object question rests on a few ideas: a reference variable holds the address of an object, not the object itself; the dot operator calls a method or reads a field; and method calls pass arguments whose types must match the parameter list. Know the difference between a class (the blueprint) and an object (an instance).
320 words, about 2 min02Selection and Iteration
Selection uses if , else if , and else , plus the short-circuit logical operators && and . Know that && stops evaluating once a false operand is found and stops at the first true operand-this matters when a later operand would throw an exception (e.g., a null check).
324 words, about 2 min03Class Creation
A class defines instance variables (private, per object), a constructor (same name as the class, no return type, initializes state), and methods (accessors and mutators). Understand encapsulation : private fields with public accessor/mutator methods.
281 words, about 1 min04Data Collections
AP CSA focuses on arrays and ArrayLists (plus 2D arrays). For arrays: fixed length via .length (a field, no parentheses), zero-based indexing, default values, and traversal with standard or enhanced for loops.
265 words, about 1 min