What is the difference between String, StringBuffer and StringBuilder?
Hello Diptangsu,
Mutability Difference:
A string is immutable, if you try to alter their values, another object gets created, whereas StringBuffer and StringBuilder are mutable so they can change their values.
Thread-Safety Difference:
The difference between StringBuffer and StringBuilder is that StringBuffer is thread-safe. So when the application needs to be run only in a single thread then it is better to use StringBuilder. StringBuilder is more efficient than StringBuffer.
Situations:
If your string is not going to change use a String class because a String object is immutable.
If your string can change (example: lots of logic and operations in the construction of the string) and will only be accessed from a single thread, using a StringBuilder is good enough.
If your string can change and will be accessed from multiple threads, use a StringBuffer because StringBuffer is synchronous so you have thread-safety.
Good luck!
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