Answer Posted / vijayakumar chinnasamy

String :
1.Content does not change –immutable

2.final class (cant subclass)

3.compareTo() - compare the string
result : < , > , = --- dictionary order

4.reverse() not available

5.is not thread safe

Criteria to choose among String
If your text is not going to change use a string Class
because a String object is immutable.



StringBuffer:

1. Content can be change Mutable

2.Final class.

3. compareTo() Not available


4.reverse() available

Allocates room for 16-addition character space when no
specific length is specified.

5.is thread safe

Criteria to choose StringBuffer

If your text can changes, and will be accessed from
multiple threads, use a StringBuffer because StringBuffer is
synchronous

You can create a string object as string str = “abc”; why cant a button object be created as button bt = “abc”;? Explain

990

---

Can we instantiate interface in java?

1128

---

Can we have multiple classes in single file ?

1067

---

Explain which of the following methods releases the lock when yield(), join(),sleep(),wait(),notify(), notifyall() methods are executed?

1117

---

What is purpose of find feature?

1080

---

What are the 2 types of java programs?

1115

---

What are generic methods?

974

---

What is the main use of generics in java?

991

---

How many types of memory areas are allocated by jvm?

1045

---

Can a final method be overloaded?

944

---

What is unicode in java?

929

---

Under what conditions is an object’s finalize() method invoked by the garbage collector?

1044

---

What Is Composition?

1055

---

why java does not support unsigned keyword?

5254

---

What are sets in java?

946

---