3.7, 3.8, 3.9, and 3.10 (part 1) | CSAwesome APCSA Java
0:00 3.7 Comparing Objects 35:37 3.8 Unit 3 - Summary 42:43 3.9 Mixed Up Code Practice 1:05:40 3.10 Toggle Mixed Up or Write Code Practice (part 1) Often classes have their own equals method, which can be used to determine whether two objects of the class are equivalent. Two object references are considered aliases when they both reference the same object. Object reference values can be compared, using == and !=, to identify aliases. A reference value can be compared with null, using == or !=, to determine if the reference actually references an object. Block of statements - One or more statements enclosed in an open curly brace { and a closing curly brace }. Boolean expression - A mathematical or logical expression that is either true or false. compound Boolean expressions - A Boolean expression with two or more conditions joined by a logical and && or a logical or ||. conditional - Used to execute code only if a Boolean expression is true. DeMorgan’s Laws - Rules about how to distribute a negation on a complex conditional. logical and - Used in compound boolean expressions that are true if both conditions are true. logical or - Used in compound boolean expressions that are true if one of the conditions is true. negation - turns a true statement false and a false statement true short circuit evaluation - The type of evaluation used for logical and (&&) and logical or (||) expressions. If the first condition is false in a compound boolean expression joined with a logical and, then the second condition won’t be evaluated. If the first condition is true in a compound boolean expression joined with a logical or then the second condition won’t be evaluate. if (Boolean expression) - used to start a conditional statement. This is followed by a statement or a block of statements that will be executed if the Boolean expression is true. else - used to execute a statement or block of statements if the Boolean expression on the if part was false. else if (Boolean expression) - used to have 3 or more possible outcomes such as if x is equal, x is greater than, or x is less than some value. It will only execute if the condition in the ‘if’ was false and the condition in the else if is true.
0:00 3.7 Comparing Objects 35:37 3.8 Unit 3 - Summary 42:43 3.9 Mixed Up Code Practice 1:05:40 3.10 Toggle Mixed Up or Write Code Practice (part 1) Often classes have their own equals method, which can be used to determine whether two objects of the class are equivalent. Two object references are considered aliases when they both reference the same object. Object reference values can be compared, using == and !=, to identify aliases. A reference value can be compared with null, using == or !=, to determine if the reference actually references an object. Block of statements - One or more statements enclosed in an open curly brace { and a closing curly brace }. Boolean expression - A mathematical or logical expression that is either true or false. compound Boolean expressions - A Boolean expression with two or more conditions joined by a logical and && or a logical or ||. conditional - Used to execute code only if a Boolean expression is true. DeMorgan’s Laws - Rules about how to distribute a negation on a complex conditional. logical and - Used in compound boolean expressions that are true if both conditions are true. logical or - Used in compound boolean expressions that are true if one of the conditions is true. negation - turns a true statement false and a false statement true short circuit evaluation - The type of evaluation used for logical and (&&) and logical or (||) expressions. If the first condition is false in a compound boolean expression joined with a logical and, then the second condition won’t be evaluated. If the first condition is true in a compound boolean expression joined with a logical or then the second condition won’t be evaluate. if (Boolean expression) - used to start a conditional statement. This is followed by a statement or a block of statements that will be executed if the Boolean expression is true. else - used to execute a statement or block of statements if the Boolean expression on the if part was false. else if (Boolean expression) - used to have 3 or more possible outcomes such as if x is equal, x is greater than, or x is less than some value. It will only execute if the condition in the ‘if’ was false and the condition in the else if is true.