java 关键字

java 关键字如下：

http://docs.oracle.com/javase/tutorial/java/nutsandbolts/_keywords.html

         Here is a list of keywords in the Java programming language. You cannot use any of the following as identifiers in your programs. The keywords const and goto are reserved, even though they are not currently used. true, false, and null might seem like keywords, but they are actually literals; you cannot use them as identifiers in your programs.

abstract            continue            for                 new                 switch             
assert***           default             goto*               package             synchronized       
boolean             do                  if                  private             this               
break               double              implements          protected           throw              
byte                else                import              public              throws             
case                enum****            instanceof          return              transient          
catch               extends             int                 short               try                
char                final               interface           static              void               
class               finally             long                strictfp**          volatile           
abstract            continue            for                 new                 switch             
assert***           default             goto*               package             synchronized       
boolean             do                  if                  private             this               
break               double              implements          protected           throw              
byte                else                import              public              throws             
case                enum****            instanceof          return              transient          
catch               extends             int                 short               try                
char                final               interface           static              void               
class               finally             long                strictfp**          volatile           
const*              float               native              super               while           

*   not used
**   added in 1.2
***   added in 1.4
****   added in 5.0

const and goto是保留字。

true, false, and null是常量。

public class Test {
    public static void main(String[] args) { 
        for (int i =1;i<=args.length;i++ ) {
            System.out.printf("%-20s",args[i-1]); 
            if(i%5==0){
                System.out.println(""); 
            }
        } 
    } 
}