| BASIC DEFINITIONS | |
|---|---|
| Class | Describes a particular kind of object. It can contain related methods and variables. |
| Method | A function defined in a class. Methods implement the behavior for objects. |
| Object | The principal building blocks of Java. Objects consist of variables (data) and methods (functionality). |
| COMMENTS | |
|---|---|
| HTML Comments | |
| <!-- comment --> | Sent to the client in the viewable page source. |
| JSP Commens (Not Sent to Client) | |
| <%-- comment --%> | Comments in JSP file. |
| // comment | Comment in scriplet part of JSP file. |
| ELEMENTS | |
|---|---|
| Declaration | |
| <%! declaration %> | Creates a global variable or method. |
| Expression | |
| <%= expression %> | Statements evaluated on the server before the page is outputted to the client. |
| Page Directive | |
| <%@ directive %> | Attributes that apply to the entire page. |
| Scriplet | |
| <% code fragment of one or more lines %> | Contains a block of scripting code which is executed when the page is generated. |
| Taglib Directive | |
| <%@ taglib uri="URIToTagLibrary" prefix="tagPrefix" %> | Defines a tag library and prefix for tags used in a JSP page. |
| SEPARATORS | |
|---|---|
| ( ) | Used to surround parameters |
| { } | Defines a block of code for a class or method or to contain the values of automatically initialized arrays |
| [ ] | Declares arrays or references array values |
| ; | Denotes the end of a statement |
| , | Separates variables |
| . | Separates package names from subpackages/ classes or a variable/method from a reference variable |
| PRIMITIVE DATA TYPES | ||
|---|---|---|
| Type | Description | Bits |
| (Integers) | ||
| byte | Byte-length integer | 8 |
| short | Short integer | 16 |
| int | Integer | 32 |
| long | Long integer | 64 |
| (Real Numbers) | ||
| float | Single-precision floating point | 32 |
| double | Double-precision floating point | 64 |
| (Other) | ||
| char | A single character | 16 |
| boolean | A boolean value (true or false) | 1 |
| OPERATORS | |
|---|---|
| + | addition of numbers, concatenation of Strings |
| += | add and assign numbers, concatenate and assign Strings |
| - | subtraction |
| -= | subtract and assign |
| * | multiplication |
| *= | multiply and assign |
| / | division |
| /= | divide and assign |
| % | take remainder |
| %= | take remainder and assign |
| ++ | increment by one |
| -- | decrement by one |
| > | greater than |
| >= | greater than or equal to |
| < | less than |
| <= | less than or equal to |
| ! | boolean NOT |
| != | not equal to |
| && | boolean AND |
| || | boolean OR |
| == | boolean equals |
| = | assignment |
| STATEMENTS |
|---|
| IF/Else |
| if (statement) { code_block_true; } else { code_block_false; } |
| While |
| while (condition) { code_block; } |