StringBuilder over StringBuffer

As String is an immutable class , any update operations  like replace/substring/append is very expensive. As solution for this StringBuffer class has been introduced for all string update related operations.

But problem with StringBuffer is that it is a synchronized class. All its public methods are tagged as “synchronized”. This adds an extra cost to string update operation whenever synchronized is actually not needed.

As part of JDK 1.5 a new utility class called StringBuilder has been introduced for non-synchronized string update operations. StringBuilder is designed as a replacement for StringBuffer in single-threaded usage.

It means using StrinBuilder instead of StringBuffer where ever synchronization is not an issue will be added to program performance.

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