AP Computer Science A - Part 1

Declare and initialize variables in Java with descriptive names and types like int, double, and boolean; use assignment and semicolon. Show printing with System.out.println and System.out.print, including GPA 3.94.

Demonstrate reassigning values with assignment statements by tracking integers a and b, using the assignment operator, and evaluating expressions like a minus b and a times b.

Use compound assignment operators to shorten expressions, including +=, ++, and --, and recognize their equivalence to a = a + b or a = a + 1.

Explore casting to produce decimal results from integer division, using double type casts to values like seven divided by two, and understand how parentheses affect casting precedence and type mismatches.

Explore ranges of variables by examining Java int limits and how overflow occurs when exceeding min and max values, and use larger data types like long to store bigger numbers.

Define objects as class instances with attributes and methods, and instantiate them with constructors using new. Explore no-argument and multi-argument constructors, including point objects with x, y, z.

Learn how to call a void method with parameters, pass arguments to a constructor and a move method, and update a point's x and y with two integers.

Learn how non-void methods return values, declare a return type like int, and store results with object.method calls, demonstrated by exposing and retrieving 23 from current location.

Explore strings as a Java data type for storing character sequences, including string literals, the string class constructor, concatenation, and escape sequences such as backslashes and newlines.

Learn Java string methods such as length, substring, equals, indexOf, and compareTo. Understand how to extract substrings with inclusive start and non-inclusive end, and how to check string equality.

Explore wrapper classes like integer and double, and learn how they represent primitives as objects using new, obtain the int value, and access min value and max value for range.

Explore the math class in Java, using abs, pow, sqrt, and random to perform exponentiation, square roots, and to generate random integers in the five to ten range.

Explore boolean expressions and if statements, mastering equality and relational operators such as == and !=, and using them to control program flow and output.

Analyze if-else statements by evaluating a boolean expression like A greater than B. Observe true and false paths, the else branch, and that code outside braces always executes.

Learn how else-if statements chain conditional branches, evaluating conditions in order so only the first true case executes and the final else handles all remaining cases.

Master compound boolean expressions by applying and, or, and not to multiple booleans. Learn how parentheses and truth values shape evaluation in real code.

Explore how to compare strings by using the equals method to check content, not references. Learn how aliasing (S3 = S1) makes objects share state.