#Lighting.java

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 */
package java2.lesson01;

/**
 *
 * @author std
 */
public class Lighting {
    enum STATUS {ON, OFF};
    
    STATUS newStatus;
    
    /**
     * status:
     *  0 -> OFF
     *  1 -> ON
     */
    int status;
    
    public void checkStatus() {
        if(status == 0) {
            System.out.println("OFF");
        } else {
            System.out.println("ON");
        }
    }
    
    public void checkStatusNew() {
        switch(newStatus) {
            case ON:
                System.out.println("ON");
                break;
            case OFF:
                System.out.println("OFF");
                break;
        }
    }
}

#Main.java

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package java2.lesson01;

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 *
 * @author std
 */
public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        
        System.out.println("Nhap chuoi: ");
        String str = scan.nextLine();
        
        String pattern = "[a-kH-W5-9]{3,9}[m-t]{5,10}";
        Pattern p = Pattern.compile(pattern);
        Matcher m = p.matcher(str);
        
        boolean isFind = false;
        while(m.find()) {
            System.out.println(m.group() + ", start: " + m.start() + ", end: " + m.end());
            isFind = true;
        }
        
        if(!isFind) {
            System.out.println("Khong tim thay");
        }
    }
}

#Test.java

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package java2.lesson01;

import java.util.ArrayList;
import java.util.Vector;

/**
 *
 * @author std
 */
public class Test {
    public static void main(String[] args) {
        ArrayList<Integer> list = new ArrayList<>();
        //Nhan xet ve ArrayList
        //  - Class Object -> Ke thua tu interface List
        //  - Bien elementData -> Mang index object -> []
        //  - size: Luu vi tri dang them phan tu vao
        //  - elementData -> 10 phan tu
        
        
        list.add(5);
        list.add(8);
        list.add(9);
        
        for (Integer v : list) {
            System.out.println("v = " + v);
        }
        
        Vector<Integer> vec = new Vector<>();
        vec.add(123);
    }
}