Java String matches Regular expression

　　

2. Package test;
4. /**
6. * Use regular expressions in the matches () method of String, Split () method.
8. * @author fhd001
10. */
12. public class Regextest {
16. public static void Main (string[] args) {
20. /*
22. * Normal characters
24. */
26. String str1 = "abc45abc345";
28. STRING[]ARR1 = Str1.split ("abc");
30. for (String string:arr1) {
32. System.out.print (string+"--");
34. }
36. System.out.println ();
42. /*
44. * Simple escape character
46. * Be sure to use a double backslash when using the literal characters in Java and two slashes to escape into a slash,
48. * Escaping those special characters with this slash character.
50. */
52. String str2 = "^$ () []{}.? +*|";  
54. Boolean flag = Str2.matches ("//^//$//(//)//[//]//{//}//.//?//+//*//|");
56. SYSTEM.OUT.PRINTLN (flag);
62. /*
64. * Escape character/q.../e.
66. */
68. String STR3 = "^$ () []{}.?  +*|99999 ";
70. Boolean flag2 = Str3.matches ("//q^$ ()" []{}.?  +*|//E//D{5} ");
72. System.out.println (FLAG2);
78. /*
80. * Character Set fit
82. */
84. String STR4 = "dfddri334";
86. Boolean flag4 = Str4.matches (". +");
88. System.out.println (FLAG4);
92. String STR5 = "#$%^* ())%";
94. Boolean flag5 = Str5.matches ("//w{9}");
96. System.out.println (FLAG5);
100. String STR6 = "4GFFMDKEKRHHR";
102. Boolean flag6 = Str6.matches ("//w+");
104. System.out.println (FLAG6);
108. String STR7 = "Fjfdke Eett";
110. Boolean Flag7 = Str7.matches ("//w+//s+//w{4}//s?");
112. System.out.println (FLAG7);
116. String str8 = "Erefff";
118. Boolean Flag8 = Str8.matches ("//s+//s+//s+");
120. System.out.println (FLAG8);
124. String STR9 = "456776888";
126. Boolean flag9 = Str9.matches ("//d+");
128. System.out.println (FLAG9);
134. String str10 = "RTYDFGRGWVR";
136. Boolean flag10 = Str10.matches ("//d+");
138. System.out.println (FLAG10);
144. /*
146. * Custom Character Set collection []
148. */
150. String Str11 = "Fdfeetg 34566";
152. Boolean flag11 = Str11.matches ("[fdetg]+//s+[3-6]+");
154. System.out.println (FLAG11);
160. String str12 = "Rtyuie 5768";
162. Boolean flag12 = Str12.matches ("[^abcdf]+//s+[^1234]+");
164. System.out.println (FLAG12);
170. /*
172. * Match number Qualifier
174. */
178. Greedy mode
180. String Str13 = "ytreggcv454444444333";
182. Boolean FLAG13 = Str13.matches ("//w{20}");
184. System.out.println (FLAG13);
188. Boolean flag14 = Str13.matches ("//w{10,21}");
190. System.out.println (FLAG14);
194. Boolean flag15 = Str13.matches ("//w{18,}");
196. System.out.println (FLAG15);
200. String str14 = "4";
202. Boolean flag16 = Str14.matches ("//d?");
204. System.out.println (FLAG16);
208. String str15 = "DDCVGT";
210. Boolean flag17 = Str15.matches ("//d+//d?");
212. System.out.println (FLAG17);
216. String str16 = "e33tf44t44t";
218. Boolean flag18 = Str16.matches ("//w+//w*");
220. System.out.println (FLAG18);
224. Reluctant mode (only one example)
226. String str17 = "34567ghjkkld";
228. Boolean flag19 = Str17.matches ("//d{2,7}?//w{8,11}");
230. System.out.println (FLAG19);
234. Possessive mode (for example only)
236. String str18 = "22222DDDDD";
238. Boolean flag20 = Str18.matches ("//d{2,5}+//w{6}");
240. System.out.println (FLAG20);
244. /*
246. * Character boundaries
248. */
250. String str19 = "A444545rot44tm";
252. Boolean flag21 = Str19.matches ("^a//w+m$");
254. System.out.println (FLAG21);
260. /*
262. * Select Expression XXX | Xxx
264. */
266. String Str20 = "ABC123ABC";
268. Boolean flag22 = Str20.matches ("(abc|123) {3}");
270. System.out.println (FLAG22);
276. /*
278. * Group ().
280. * The above modifiers are decorated for one character. If you want to do a group of characters
282. * The decoration will be used ()
284. */
286. String Str21 = "123qwe123qwe";
288. Boolean flag23 = Str21.matches ("(123qwe) {2}");
290. System.out.println (FLAG23);
296. /*
298. * [] The intersection and the set
300. */
302. String str22 = "abcdefgh1234567";
304. Boolean flag24 = Str22.matches ("[a-z1-9]+"); and set
306. System.out.println (FLAG24);
310. Boolean flag25 = Str22.matches ("[a-z1-9&&[a-h1-7]]+");//Intersection
312. System.out.println (FLAG25);
314. }
316. }

Result code

1. -45-->345-->
2. True
3. True
4. True
5. True
6. True
7. True
8. True
9. True
10. True
11. True
12. True
13. True
14. True
15. True
16. True
17. True
18. True
19. True
20. False
21. True
22. True
23. True
24. True
25. True

Java String matches Regular expression