First, identifiersconcept: is used to give the program in the variables, classes, methods named symbols;identifier rules: Identifiers can consist of letters, numbers, underscores _, and dollar sign $, and numbers do not beginidentifiers cannot make Java keywords and reserved words, but can contain keywords and reserved wordsidentifiers cannot contain spacesidentifiers can only contain dollar sign $ and cannot contain @, #等其他特殊字符delimiter: semicolon; curly brace {} square brackets [] brackets () space dots.;
second, the Java keywordJava contains 50 keys, all the keywords are lowercase
keyword list:
Abstract assert of abstraction
boolean
break
byte
case
catch
char
const (reserved word)
continue
default
do
Double
Else
enum
extends
final
finally
float
for
if
goto (reserved word)
implements
import
int Interface
Long native
New Package
Private protectedPublic
returnShort
Static
STRICTFP Super
Switch SynchronizedThis
throw
throws transient
try void
volatile while
three special Direct quantities (iteral); True false null is not a keyword
final modifier variable, equivalent to constantthe parameters in the final decoration method are called final parameters. final decorated class, the class cannot be inheritedFinal decoration method, the method cannot be overridden.
Java Identifiers and keywords
