Adv-Java Unit 3: Complete Concepts Guide

import javax.swing.*;

public class SwingExample {
    public static void main(String[] args) {
        JFrame frame = new JFrame("My First Swing Program");
        JLabel label = new JLabel("Welcome to Java Swing");
        label.setBounds(80, 50, 200, 30);

        JButton button = new JButton("Click Me");
        button.setBounds(100, 100, 120, 40);
        button.addActionListener(e ->
            JOptionPane.showMessageDialog(frame, "Button Clicked!"));

        frame.add(label);
        frame.add(button);
        frame.setSize(350, 250);
        frame.setLayout(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

┌──────────────────────────────────────┐
│ My First Swing Program           X   │
├──────────────────────────────────────┤
│                                      │
│      Welcome to Java Swing           │
│                                      │
│         ┌───────────┐                │
│         │ Click Me  │                │
│         └───────────┘                │
│                                      │
└──────────────────────────────────────┘

1. Import Swing
2. Create JFrame
3. Create JLabel
4. Set label position
5. Create JButton
6. Set button position
7. Tell button what to do when clicked
8. Add label to JFrame
9. Add button to JFrame
10. Set JFrame size
11. Set layout
12. Set close operation
13. Make JFrame visible
14. User clicks "Click Me"
15. ActionListener runs
16. "Button Clicked!" appears

public class SwingDemo {
    public static void main(String[] args) {
        System.out.println("Project Created Successfully");
    }
}

Project Created Successfully

package student;

public class Student {
}

public class DebugExample {
    public static void main(String[] args) {
        int a = 10;
        int b = 20;
        int c = a + b;          // Breakpoint here
        System.out.println(c);
    }
}

import javax.swing.*;

public class LabelDemo {
    public static void main(String[] args) {
        JFrame f = new JFrame();
        JLabel label = new JLabel("Welcome");
        label.setBounds(100, 100, 150, 30);
        f.add(label);
        f.setSize(300, 300);
        f.setLayout(null);
        f.setVisible(true);
    }
}

import javax.swing.*;

public class TextFieldDemo {
    public static void main(String[] args) {
        JFrame f = new JFrame();
        JTextField tf = new JTextField();
        tf.setBounds(50, 50, 150, 30);
        f.add(tf);
        f.setSize(300, 300);
        f.setLayout(null);
        f.setVisible(true);
    }
}

import javax.swing.*;

public class ButtonDemo {
    public static void main(String[] args) {
        JFrame f = new JFrame();
        JButton b = new JButton("Click");
        b.setBounds(100, 100, 100, 30);
        f.add(b);
        f.setSize(300, 300);
        f.setLayout(null);
        f.setVisible(true);
    }
}

import javax.swing.*;

public class CheckBoxDemo {
    public static void main(String[] args) {
        JFrame f = new JFrame();
        JCheckBox cb = new JCheckBox("Java");
        cb.setBounds(100, 100, 100, 30);
        f.add(cb);
        f.setSize(300, 300);
        f.setLayout(null);
        f.setVisible(true);
    }
}

import javax.swing.*;

public class FrameDemo {
    public static void main(String[] args) {
        JFrame frame = new JFrame("My Frame");
        frame.setSize(400, 300);
        frame.setVisible(true);
    }
}

import javax.swing.*;

public class PanelDemo {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        JPanel panel = new JPanel();
        panel.add(new JButton("Save"));
        frame.add(panel);
        frame.setSize(300, 300);
        frame.setVisible(true);
    }
}

frame.setLayout(new FlowLayout());

frame.setLayout(new BorderLayout());

frame.setLayout(new GridLayout(2, 2));

A B
C D

Button → ActionEvent → ActionListener

import javax.swing.*;
import java.awt.event.*;

public class ActionDemo {
    public static void main(String[] args) {
        JFrame f = new JFrame();
        JButton b = new JButton("Click");
        b.setBounds(100, 100, 100, 30);
        b.addActionListener(e -> System.out.println("Button Clicked"));
        f.add(b);
        f.setSize(300, 300);
        f.setLayout(null);
        f.setVisible(true);
    }
}

button.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        System.out.println("Clicked");
    }
});

import java.awt.event.*;

public class Demo extends WindowAdapter {
    public void windowClosing(WindowEvent e) {
        System.exit(0);
    }
}

Name:   [__________]
Age:    [__________]
Course: [__________]
[Save]  [Reset]

JButton save = new JButton("Save");

button.addActionListener(e -> System.out.println("Saved"));

JFrame + JLabel + JTextField + JButton

[ 10 ]
[ + ] [ - ]
[ * ] [ / ]
[ = ]

int result = num1 + num2;

button.addActionListener(e -> {
    int a = 10;
    int b = 20;
    System.out.println(a + b);
});

resultField.setText(String.valueOf(result));

JButton add = new JButton("+");
add.addActionListener(e -> {
    int a = Integer.parseInt(t1.getText());
    int b = Integer.parseInt(t2.getText());
    result.setText(String.valueOf(a + b));
});

Connection con = DriverManager.getConnection(url, user, password);

Class.forName("com.mysql.cj.jdbc.Driver");
Connection con = DriverManager.getConnection(
    "jdbc:mysql://localhost/test", "root", "root");

ResultSet rs = stmt.executeQuery("SELECT * FROM student");
while (rs.next()) {
    System.out.println(rs.getString("name"));
}

stmt.executeUpdate("INSERT INTO student VALUES(1,'Rahul')");

stmt.executeUpdate("UPDATE student SET name='Amit'");

stmt.executeUpdate("DELETE FROM student");

INSERT INTO employee VALUES(101,'John');

UPDATE product SET quantity=50 WHERE id=1;

        Spring
          |
    Spring Container
          |
    ----------------------------
    |      |      |      |
 Student Teacher Course Fee
    |      |      |      |
    ----------- Dependencies ---

SPRING FRAMEWORK
       |
       ↓
 Spring Container
       |
 IoC + Dependency Injection
       |
 Managed Objects (Beans)
       |
 ---------------------------------------
 |      |      |      |      |
 MVC   JDBC   ORM  Security  AOP
 |      |      |      |      |
 Web  Database JPA/ Login/  Logging/
               Hibernate Transactions

public class Student {
    private int id;
    private String name;
}

Spring Framework
|
|-- Core Container
|-- Spring MVC
|-- Spring JDBC
|-- Spring ORM
|-- Spring Security
|-- Spring AOP

public class StudentService {
    StudentDAO dao = new StudentDAO();   // Tightly coupled
}

@Autowired
private StudentDAO dao;   // Spring injects automatically

@Transactional
public void saveStudent() {
}

Application
    |
--------------------------------
| Core Container               |
| Data Access Layer            |
| Web Layer                    |
| Integration Layer            |
--------------------------------

ApplicationContext context =
    new ClassPathXmlApplicationContext("beans.xml");

JdbcTemplate jdbcTemplate;

@Controller
public class HomeController {
}

@Repository
public class StudentDAO {
}

StudentDAO dao = new StudentDAO();   // Programmer creates objects

@Autowired
StudentDAO dao;   // Spring creates and injects objects

Application
    ↓
Spring Container
    ↓
Object Creation
    ↓
Dependency Injection

@Component
public class Student {
}

<bean id="student" class="com.demo.Student"/>

ApplicationContext context =
    new ClassPathXmlApplicationContext("beans.xml");

public class StudentService {
    private StudentDAO dao;

    public StudentService(StudentDAO dao) {
        this.dao = dao;
    }
}

<bean id="dao" class="StudentDAO"/>
<bean id="service" class="StudentService">
    <constructor-arg ref="dao"/>
</bean>

public class StudentService {
    private StudentDAO dao;

    public void setDao(StudentDAO dao) {
        this.dao = dao;
    }
}

<property name="dao" ref="dao"/>

@Service
public class StudentService {
    @Autowired
    private StudentDAO dao;
}

@Autowired
private StudentDAO dao;

@Component
@Scope("singleton")
public class Student {
}

Request 1 → Same Object
Request 2 → Same Object
Request 3 → Same Object

@Component
@Scope("prototype")
public class Student {
}

Request 1 → Object 1
Request 2 → Object 2
Request 3 → Object 3

@PostConstruct
public void init() {
    System.out.println("Bean Initialized");
}

@PreDestroy
public void destroy() {
    System.out.println("Bean Destroyed");
}

1. Bean Instantiation
2. Dependency Injection
3. @PostConstruct (init)
4. Bean Ready for Use
5. @PreDestroy (destroy)
6. Bean Removed

Browser
    ↓
DispatcherServlet
    ↓
Controller
    ↓
View

<servlet>
    <servlet-name>dispatcher</servlet-name>
    <servlet-class>
        org.springframework.web.servlet.DispatcherServlet
    </servlet-class>
</servlet>

<context:component-scan base-package="com.demo"/>

@Controller
public class HomeController {
}

@RequestMapping("/home")
public String home() {
    return "home";
}

<bean class="InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/views/"/>
    <property name="suffix" value=".jsp"/>
</bean>

@RequestMapping("/student")
public String student() {
    return "student";
}

@RequestMapping(value="/save", method=RequestMethod.POST)

<%@ taglib prefix="form"
    uri="http://www.springframework.org/tags/form"%>

<form:form modelAttribute="student">
    <form:input path="name"/>
</form:form>

public class Student {
    private String name;
}

<form:input path="name"/>

@NotNull
private String name;

<form:errors path="name"/>

@NotEmpty
private String name;

@Email
private String email;

public class Student {
    @NotEmpty
    private String name;

    @Email
    private String email;
}

@PostMapping("/save")
public String save(@Valid Student student, BindingResult result) {
    if (result.hasErrors()) {
        return "form";
    }
    return "success";
}

<form:errors path="name"/>
<form:errors path="email"/>

JAVA SWINGS & SPRING
│
├── Introduction to Java Swings
│   ├── GUI toolkit
│   ├── Platform independent
│   ├── Lightweight components
│   └── Simple Swing example
│
├── Introduction to IDE
│   ├── Features (editor, auto-complete, debugging)
│   ├── Project creation
│   ├── Code management
│   └── Debugging tools
│
├── Swing Components
│   ├── JLabel, JTextField, JButton
│   ├── JCheckBox, JRadioButton
│   └── JComboBox, JTable
│
├── Containers and Controls
│   ├── JFrame (top-level container)
│   ├── JPanel (grouping)
│   ├── Layout Managers (Flow, Border, Grid)
│   └── Event controls
│
├── Event Handling
│   ├── Delegation Event Model
│   ├── Action events
│   ├── Event listeners
│   └── Event adapters
│
├── Desktop Application Development
│   ├── GUI design principles
│   ├── Calculator application
│   ├── Database connectivity (JDBC + Swing)
│   └── Case studies (Student, Library, Employee, Inventory)
│
├── Spring Framework Fundamentals
│   ├── Features (lightweight, modular, DI, enterprise)
│   ├── Architecture (Core, Data, Web, Integration)
│   ├── Inversion of Control (IoC)
│   └── Dependency Injection (Constructor, Setter, Field)
│
├── Bean Scope and Lifecycle
│   ├── Singleton scope
│   ├── Prototype scope
│   ├── @PostConstruct
│   └── @PreDestroy
│
├── Spring MVC Configuration
│   ├── DispatcherServlet
│   ├── Configuration files
│   ├── Controller setup
│   └── View resolver
│
├── Request Mapping and Form Tags
│   ├── @RequestMapping
│   ├── URL mapping
│   ├── Form tag library
│   └── Data binding
│
└── Spring Validation
    ├── Validation framework
    ├── Error handling
    ├── Validation annotations
    └── Form validation techniques