Regular expression example in java

Examples of regular expression use in Java (see java for a full explanation of regular expression use):

The test code

package test; 
/** 
 *  in String the matches() methods ,split() Method USES regular expressions . 
 * @author fhd001 
 */ 
public class RegexTest { 
 
  public static void main(String[] args) { 
 
    /* 
     *  Normal character  
     */ 
    String str1 = "abc45abc345"; 
    String[]arr1 = str1.split("abc"); 
    for (String string : arr1) { 
      System.out.print(string+"-->"); 
    } 
    System.out.println(); 
     
     
    /* 
     *  Simple escape characters  
     *  in java When escaping a character 1 Make sure you use double backslashes , Escape the two slashes 1 A slash , 
     *  Escape those special characters with this slash character . 
     */ 
    String str2 = "^$()[]{}.?+*|"; 
    boolean flag = str2.matches("//^//$//(//)//[//]//{//}//.//?//+//*//|"); 
    System.out.println(flag); 
     
     
    /* 
     *  Escape character  /Q.../E. 
     */ 
    String str3 = "^$()[]{}.?+*|99999"; 
    boolean flag2 = str3.matches("//Q^$()[]{}.?+*|//E//d{5}"); 
    System.out.println(flag2); 
     
     
    /* 
     *  Character set  
     */ 
    String str4 = "dfddri334"; 
    boolean flag4 = str4.matches(".+"); 
    System.out.println(flag4); 
     
    String str5 = "#$%^*())%"; 
    boolean flag5 = str5.matches("//W{9}"); 
    System.out.println(flag5); 
     
    String str6 = "4gffmdkekrhhr"; 
    boolean flag6 = str6.matches("//w+"); 
    System.out.println(flag6); 
     
    String str7 = "fjfdke  eett "; 
    boolean flag7 = str7.matches("//w+//s+//w{4}//s?"); 
    System.out.println(flag7); 
     
    String str8 = "  erefff  "; 
    boolean flag8 = str8.matches("//s+//S+//s+"); 
    System.out.println(flag8); 
     
    String str9 = "456776888"; 
    boolean flag9 = str9.matches("//d+"); 
    System.out.println(flag9); 
     
     
    String str10 = "rtydfgrgwvr "; 
    boolean flag10 = str10.matches("//D+"); 
    System.out.println(flag10); 
     
     
    /* 
     *  Custom character set  [ ] 
     */ 
    String str11 = "fdfeetg 34566"; 
    boolean flag11 = str11.matches("[fdetg]+//s+[3-6]+"); 
    System.out.println(flag11); 
     
     
    String str12 = "rtyuie  5768"; 
    boolean flag12 = str12.matches("[^abcdf]+//s+[^1234]+"); 
    System.out.println(flag12); 
     
     
    /* 
     *  Match the number qualifier  
     */ 
     
    // Greed mode  
    String str13 = "ytreggcv454444444333"; 
    boolean flag13 = str13.matches("//w{20}"); 
    System.out.println(flag13); 
     
    boolean flag14 = str13.matches("//w{10,21}"); 
    System.out.println(flag14); 
     
    boolean flag15 = str13.matches("//w{18,}"); 
    System.out.println(flag15); 
     
    String str14 = "4"; 
    boolean flag16 = str14.matches("//d?"); 
    System.out.println(flag16); 
     
    String str15 = "ddcvgt"; 
    boolean flag17 = str15.matches("//D+//d?"); 
    System.out.println(flag17); 
     
    String str16 = "e33tf44t44t"; 
    boolean flag18 = str16.matches("//w+//W*"); 
    System.out.println(flag18); 
     
    // Force model ( Only for 1 case ) 
    String str17 = "34567ghjkkld"; 
    boolean flag19 = str17.matches("//d{2,7}?//w{8,11}"); 
    System.out.println(flag19); 
     
    // Possession of pattern ( Only for 1 case ) 
    String str18 = "22222ddddd"; 
    boolean flag20 = str18.matches("//d{2,5}+//w{6}"); 
    System.out.println(flag20); 
     
    /* 
     *  Characters of the boundary  
     */ 
    String str19 = "a444545rot44tm"; 
    boolean flag21 = str19.matches("^a//w+m$"); 
    System.out.println(flag21); 
     
     
    /* 
     *  Selective expression  xxx | xxx 
     */ 
    String str20 = "abc123abc"; 
    boolean flag22 = str20.matches("(abc|123){3}"); 
    System.out.println(flag22); 
     
     
    /* 
     *  grouping  ( ). 
     *  The above modifiers are for 1 Three characters . If you want to 1 Group character proceeding  
     *  You need to modify () 
     */ 
    String str21 = "123qwe123qwe"; 
    boolean flag23 = str21.matches("(123qwe){2}"); 
    System.out.println(flag23); 
     
     
    /* 
     * [] The intersection and union of  
     */ 
    String str22 = "abcdefgh1234567"; 
    boolean flag24 = str22.matches("[a-z1-9]+");    // And set  
    System.out.println(flag24); 
     
    boolean flag25 = str22.matches("[a-z1-9&&[a-h1-7]]+"); // intersection  
    System.out.println(flag25); 
  } 
} 
 

The resulting code

-->45-->345--> 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
true 
false 
true 
true 
true 
true 
true 

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