各章節(jié)AP計算機科學知識點梳理（上）

 

　　計算機作為當前最被看好的一大專業(yè)領域，很多同學們在AP課程學習期間會選修AP計算機科學這門課來幫助自己打好知識基礎。今天A+國際教育小編就帶大家梳理一下各章節(jié)中AP計算機知識點內容，來幫助同學們更為系統(tǒng)地開展AP計算機科學的學習和備考工作。

　　1. Introductory Java Language Features

　　Package And Classes 類和包

　　public class FirstProg // file name is FirstProg.java { public static type1 method1 (parameter list) {} public static type2 method2 (parameter list) {} ...... public static void main (String[] args) {} }

　　All java methods must be contained in a class; all program statement must be placed in a method

　　The class that contains the main method does not contain many additional methods.

　　reserved words (Keywords): class, public, static, void, main.

　　public: the class or method is usable outside of the class

　　static: methods that will not access any objects of a class. The main method must always be static.

　　Types And Identifiers 標識符和類型

　　Identifiers 標識符

　　Identifier: name for a variable, parameter, constant, user-defined method, user-defined class

　　cannot begin with a digit

　　Lowercase: for variables and methods

　　Uppercase: separate into multiple words e.g getName, findSurfaceArea

　　a class name starts with a capitol letter

　　Built-in Types 內置類型

　　int - 整數 boolean - true or false double - 小數

　　Storage of Numbers 數值儲存

　　Integers 整數 binary Integer.MAX_VALUE == 2^31-1 Integer.MIN_VALUE == - 2^31 Floating-Point Numbers 浮點數 float & double

　　sign * mantissa * 2^exponent

　　round-off error - when floating-point numbers are converted into binary, most cannot be represented exactly

　　e.g 0.1*26 ≠ 0.1+0.1......(26 terms)

　　NaN"not a number" - undefined number

　　Hexadecimal Numbers 十六進制數

　　conversion between hex and binary 5 hex = 0101 bin         F hex = 1111 bin 5F hex = 01011111 bin

　　Final Variable  Final變量

　　user-defined constant

　　keyword final

　　e.g.   final double TAX_RATE = 0.08;

　　final variable can be declared without initializing it immediately, but can only be given just once

　　array bound

　　final int MAXSTUDENTS = 25;

　　int [] classList = new Int[MAXSTUDENTS];

　　Operators 運算符

　　Arithmetic Operators 算數運算符

　　+ addition   - subtraction   * multiplication   /devision   %mod(remainder)

　　Relational Operators 關系運算符

　　== equal to   != not equal to   > greater than   < less than   >= greater or equal to   <= less than or equal to

　　Relational Operators can only be used in comparison of primitive types.

　　User defined types : equals, compareTo  methods

　　floating-point should not be compared directly using relational operators.

　　Logical Operators 邏輯運算符

　　! NOT   && AND   || OR Short-circuit evaluation evaluated from left to right evaluation automatically stops as soon as the value of the entire expression is known

　　Assignment Operators 賦值運算符

　　Compound assignment operators : =      +=      -=      *=      /=      %=

　　Increment and Decrement Operator 遞增遞減運算符

　　++      --

　　Operator Precedence 運算符的優(yōu)先級

　　!, ++ , --                                          right to left

　　* , / , %                                           left to right + , -                                                 left to right <,>, <=,>=                                    left to right == , !=                                            left to right && || =, +=, -+, *=, /=, %=                    right to left

　　Input/Output 輸入輸出

　　Escape sequences 轉義字符

　　\n      newline \"      double quot \\       backslash

　　Control Structures 控制結構

　　Decision-Making Control Structures 條件結構

　　if...

　　if...else...

　　nested if

　　extended if (if...elseif...)

　　Iteration 循環(huán)結構

　　for loop

　　for (initialization; termination condition; update statement)

　　The termination condition is tested at the top of the loop

　　the update statement is performed at the bottom

　　loop variable should not have its value changed inside the loop body

　　the scope of the loop variable can be restricted to the loop body by combining the loop variable declaration with the initialization.

　　for-each loop

　　for (SomeType element : collection)

　　cannot be used to replace or remove elements

　　hides the index variable that is used with array

　　while loop

　　while (boolean test)

以上就是A+國際教育小編關于部分AP計算機科學知識點內容的梳理，當然由于篇幅有限，小編只更新了部分內容，其余部分將在接下來幾天中列舉。歡迎持續(xù)關注喲！