Will Java provide default constructor by own?

Yes, Java automatically provides a default constructor—but only under one condition:

🧾 When Does Java Provide a Default Constructor?

Java will insert a default (no-argument) constructor only if:

• You do not define any constructors yourself in the class.

📌 What Is a Default Constructor?

It’s a constructor that:

• Takes no parameters
• Has no code except calling the superclass constructor (super())

📦 Example: Provided by Java

public class Person {
    // No constructor defined

    // Java will generate this behind the scenes:
    // public Person() { super(); }
}

✅ You can now create objects like:

Person p = new Person();  // Works fine

⚠️ Important: If You Define Any Constructor…

If you define even one constructor (with or without parameters), Java will not add a default constructor automatically.

❌ Example:

public class Person {
    public Person(String name) {
        // Custom constructor
    }
}

Person p = new Person();  // ❌ Error: no default constructor

You’d have to manually add it like:

public Person() {
    // optional default behavior
}

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