Difference between String ,String Builder and String Buffer

                                                           

String :

 String is immutable object i.e. once created cannot be changed.
object created is stored in Constant Spring pool.
Immutable objects means they can't be modified.
They are thread safe means can be used by only single thread at a time.

e.g. String value1="test";

this object is stored in constant pool and value cannot be modified.

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StringBuffer :


StringBuffer is mutuable i.e. values can be changed.

It is defined as

String value1= new String ("test");

These values are stored in heap and can be modified at later point  of time

i.e. value1=new String ("testing");

now value1 is referring to an object which has value "testing".

 String Buffer is also synchronized means thread-safe.

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String Builder :

String builder is also as same as String Buffer .It also stores value in heap.But unlike StringBuffer , String Builder is non synchronized which makes it working faster.


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