Which is faster stringbuffer or stringbuilder

Viewed k times. Improve this question. Raedwald Add a comment. Active Oldest Votes. Improve this answer. Only place I see for a StringBuffer is console like output and various logging utility: many thread may output in conflict.

Since you don't want 2 output to get mixed up It would save code review time with newbies. Good mnemonic for those who mix these two - BuFFer was First, older and therefore synchronized implementation.

Newer Builder class uses Builder pattern and is asynchronous. Show 9 more comments. ACV 8, 5 5 gold badges 61 61 silver badges 73 73 bronze badges. I changed the string literal to something larger: "the quick brown fox " and got more interesting results. Basically, they are about as fast.

I actually ran out of memory so I had to remove a few sevens. Explanation: the synchronization is optimized away by hotspot. You are basically just measuring the time it takes hotspot to do this and probably some more optimizations. You need to warm up before.

This test is unfair to StringBuffer. Also, it would be good if it actually appended something. Actually, I flipped the test, and appended a random string and got the opposite test. Goes to say, that one cannot trust simple benchmarks. The opposite shows StringBuffer is faster. Took me a moment to realize what it means.

Is this something that is actually used in practice instead of the usual Others conclude with different results: alblue. Benchmarks should really be done with JMH, not with a simple main Also, your benchmark is unfair. There's no warmup. Show 6 more comments. That's pretty much about it.

So it was made to substitute it. The same happened with Vector and ArrayList. Ashish Kumar 2 2 gold badges 15 15 silver badges 31 31 bronze badges. OscarRyz OscarRyz k gold badges silver badges bronze badges. Also with Hashtable and HashMap.

But needed to get the clear difference with the help of an example? StringBuffer or StringBuilder Simply use StringBuilder unless you really are trying to share a buffer between threads.

Community Bot 1 1 1 silver badge. Bert F Bert F The first good answer!! The point is "unless you are sharing a buffer between threads" — AlexWien. Basically, don't just assume that using a thread-safe library immediately guarantees thread-safety in YOUR program! Nicolas Zozol Nicolas Zozol 6, 3 3 gold badges 48 48 silver badges 67 67 bronze badges. So the figure displayed for StringBuilder is actually time it took to run stringbuffer AND stringbuilder test. You should use JMH for benchmarks. Your benchmark is really inaccurate.

StringBuilder was introduced in Java 1. MrTux Marc Novakowski Marc Novakowski Also BlackBerry java is based on 1. Common thing :- Both have same methods with same signatures. Both are mutable. Sireesh Yarlagadda Sireesh Yarlagadda AJPerez 3, 8 8 gold badges 60 60 silver badges 87 87 bronze badges. JRomio JRomio 2, 2 2 gold badges 23 23 silver badges 27 27 bronze badges. NOTE: Only single operations are thread-safe, multiple operations are not. Learning Learning 7, 3 3 gold badges 30 30 silver badges 45 45 bronze badges.

StringBuffer StringBuffer is mutable means one can change the value of the object. Afee Afee 2, 26 26 silver badges 33 33 bronze badges. StringBuilder is immutable and String type is mutable — Brinda Rathod. See the above answers. Example of good usage: If your text is going to change and is used by multiple threads, then it is better to use StringBuffer.

Nikolai Samteladze 7, 4 4 gold badges 42 42 silver badges 70 70 bronze badges. String is an immutable. StringBuffer is a mutable and synchronized. StringBuilder is also mutable but its not synchronized. Ani Menon Additionally StringBuffer locks Threads for access this thread safe data that's why operation goes slowly. StringBuilder does not lock thread and it runs in Multi Threading way that's why is fast. The javadoc explains the difference: This class provides an API compatible with StringBuffer, but with no guarantee of synchronization.

Zohra Khan Zohra Khan 4, 3 3 gold badges 24 24 silver badges 32 32 bronze badges. Kevin Lee Kevin Lee 2, 23 23 silver badges 31 31 bronze badges.

Pops Ahmad adawi Ahmad adawi 59 1 1 bronze badge. Android Genius Android Genius 1 1 silver badge 6 6 bronze badges. So we have come to a conclusion that StringBuffer is a thread-safe class while StringBuffer isn't. Is that something you should worry about? If you are working on application which uses multiple threads it can be potentially dangerous to work with StringBuilder. Speed : StringBuffer is actually two to three times slower than StringBuilder.

The reason behind this is StringBuffer synchronization - only allowing 1 thread to execute on an object at a time results in much slower code execution. Both StringBuffer and StringBuilder have the same methods besides synchronized method declaration in the StringBuilder class.

Let's go through some of the most common ones:. As you can see the each method name pretty much describes what it does. Here is a simple demonstration:. Note : As we can see from the table above, String is both less efficient in time and memory, but that doesn't mean we should never use it again. In order to show how much efficient String , StringBuffer , and StringBuilder are we are going to perform a benchmark test:. This output may vary depending on your Java Virtual Machine. So from this benchmark test we can see that StringBuilder is the fastest in string manipulation.

Next is StringBuffer , which is between two and three times slower than StringBuilder. And finally we have String which is by far the slowest in string manipulation. What it would take StringBuilder to concatenate in 1 second would take String 1. We have seen the performance of String s, StringBuffer s, and StringBuilder s as well as their pros and cons. Now, the final question arises:.

Well the perfect answer on this question is "It depends". We know that String s are easy to type, easy to use, and are thread-safe. On the other hand they are immutable which means more memory consumption and very slow when doing string manipulation.

StringBuilder is not synchronized, which in turn means it is not thread-safe. StringBuilder also has four defined constructors; they are as follows:. So as we can see that StringBuffer and StringBuilder seem to be the same. Even though they have similar functionality, they are quite different, and you might be better off using one rather than the other in many cases.

In cases where the string has to be accessed by multiple threads and no external synchronization is applied, you must use StringBuffer and not StringBuilder. StringBuilder is not a thread-safe class, whereas StringBuffer has this characteristic; this is due to the fact that StringBuffer is synchronized.

Due to the above two characteristics, StringBuffer is slower compared to StringBuilder. StringBuilder wad introduced in Java 1. As we can learn from the points above, StringBuilder is faster when it comes to performance compared to StringBuffer. Memory Consumption among the two is also different where StringBuffer consumes more memory compared to the latter.

Even though StringBuilder is classified as an alternative to the string class like StringBuffer, but it is a lot more flexible when it comes to usage.

So, As you can see that if you want to modify strings which by default are an immutable set of characters, you have to use StringBuffer or StringBuilder classes as they provide the ability to change strings. Both the classes are similar on the surface, as you can see, they use the same methods and similar constructors.

The difference between the two comes down to the synchronization and threading. Data Science. Data Science All Courses M. Sc in Data Science — University of Arizona. Software Engineering All Courses M.