Write a regular expression to validate a password. A password must start with an alphabet and followed by alphanumeric characters; its length must be in between 8 to 20.

1021

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How to perform merge sort in java?

1055

---

What is a lightweight component?

1019

---

What are the types of inner classes (non-static nested class) used in java?

1056

---

How to make a write-only class in java?

1055

---

How many types of exception can occur in a java program?

985

---

What are the differences between this and super keyword?

939

---

Do I need to import java.lang package any time? Why?

1381

---

Why are the objects immutable in java?

983

---

Can we modify the throws clause of the superclass method while overriding it in the subclass?

1031

---

How can you avoid serialization in child class if the base class is implementing the serializable interface?

1079

---

Can you make a constructor final?

1036

---

How can constructor chaining be done by using the super keyword?

1091

---

What do you understand by copy constructor in java?

925

---

What is the final blank variable?

1132

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