1 package com.jdk7.chapter5;
2
3 public class JavaIdentifier {
4
5 /**
6 * 使用Character.isJavaIdentifierPart判断字符是否属于java标识符
7 it is a letter
8 it is a currency symbol (such as '$')
9 it is a connecting punctuation character (such as '_')
10 it is a digit
11 it is a numeric letter (such as a Roman numeral character)
12 it is a combining mark
13 it is a non-spacing mark
14 '\u005Cu0000' through '\u005Cu0008'
15 '\u005Cu000E' through '\u005Cu001B'
16 '\u005Cu007F' through '\u005Cu009F'
17 * @param str
18 * @return
19 */
20 public static boolean isJavaIdentifier(String str){
21 if(str==null || str.length()==0){
22 return false;
23 }
24 char[] ch = str.toCharArray();
25 for(int i=0;i<ch.length;i++){
26 if(!(Character.isJavaIdentifierPart(ch[i]))){
27 return false;
28 }
29 }
30 return true;
31 }
32
33 public static void main(String[] args) {
34 System.out.println("my_var is an identifier? "+JavaIdentifier.isJavaIdentifier("my_var"));
35 System.out.println("$my_var is an identifier? "+JavaIdentifier.isJavaIdentifier("$my_var"));
36 System.out.println("my_var.1 is an identifier? "+JavaIdentifier.isJavaIdentifier("my_var.1"));
37 System.out.println("1$my_var is an identifier? "+JavaIdentifier.isJavaIdentifier("1$my_var"));
38 System.out.println("u0391var is an identifier? "+JavaIdentifier.isJavaIdentifier("u0391var"));
39 System.out.println("null is an identifier? "+JavaIdentifier.isJavaIdentifier(null));
40 System.out.println("null is an identifier? "+JavaIdentifier.isJavaIdentifier(" "));
41 }
42 }
43
44
45 执行结果：
46 my_var is an identifier? true
47 $my_var is an identifier? true
48 my_var.1 is an identifier? false
49 1$my_var is an identifier? true
50 u0391var is an identifier? true
51 null is an identifier? false
52 null is an identifier? false
来源：oschina
链接：https://my.oschina.net/u/4388097/blog/4239382