java regular expressions extract the required characters and put them into an array.

This article demonstrates how the java regular expression implementation extracts the required characters and puts them into an array. I will share it with you for your reference as follows:

Here we demonstrate that the Java regular expression extracts the required characters and puts them into an array, the ArrayList array, to repeat the function.

The specific code is as follows:

package com.test.tool;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.regex.*;
public class MatchTest {
  public static void main(String[] args)
  {
    String regex = "[0-9]{5,12}";
    String input = "QQ120282458 . QQ120282458 QQ125826";
    Pattern p = Pattern.compile(regex);
    Matcher m = p.matcher(input);
    ArrayList al=new ArrayList();
    while (m.find()) {
      al.add(m.group(0));
    }
    System.out.println(" Before removing duplicates ");
    for (int i=0;i<al.size();i++)
    {
      System.out.println(al.get(i).toString());
    }
    // Get rid of duplicates 
    HashSet hs=new HashSet(al);
    al.clear();
    al.addAll(hs);
    System.out.println(" After removing the duplicates ");
    for (int i=0;i<al.size();i++)
    {
      System.out.println(al.get(i).toString());
    }
  }
}

The output result is:

 Before removing duplicates 
120282458
120282458
125826
 After removing the duplicates 
125826
120282458

Improved version: make 1 bean:

package com.test.tool;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.regex.*;
public class MatchTest {
  private String regex;
  private String input;
  private ArrayList al;
  public String getRegex() {
    return regex;
  }
  public void setRegex(String regex) {
    this.regex = regex;
  }
  public String getInput() {
    return input;
  }
  public void setInput(String input) {
    this.input = input;
  }
  public ArrayList getAl() {
    return al;
  }
  public void setAl(ArrayList al) {
    this.al = al;
  }
  public MatchTest(String regex,String input)
  {
    Pattern p=Pattern.compile(regex);
    Matcher m=p.matcher(input);
    ArrayList myal=new ArrayList();
    while (m.find())
    {
      myal.add(m.group());
    }
    HashSet hs=new HashSet(myal);
    myal.clear();
    myal.add(hs);
    this.setRegex(regex);
    this.setInput(input);
    this.setAl(myal);
  }
  public MatchTest(){}
  public static void main(String[] args){
     String regex1 = "[0-9]{5,12}";
     String input1="QQ120282458 . QQ120282458 QQ125826";
     //String input1="QQ";
    MatchTest mt=new MatchTest(regex1,input1);
    for (int i=0;i<mt.getAl().size();i++)
    {
      System.out.println(mt.getAl().get(i).toString());
    }
  }
}

PS: here are two more handy regular expression tools for you to use:

JavaScript regular expression online testing tool:
http://tools.ofstack.com/regex/javascript

Online regular expression generation tool:
http://tools.ofstack.com/regex/create_reg

I hope this article is helpful to you java programming.