Similar to the StringBuffer, the StringBuilder keeps the object in a heap and allows for modification. The key distinction between StringBuffer and StringBuilder is that ThreadSafe is not a feature of StringBuilder. Since StringBuilder is not thread-safe, it is quick. Strings are also immutable since arrays are immutable (cannot expand). A completely new string is produced whenever a string is modified. Java has a number of classes via which strings may be utilized, though. 

Java uses the classes StringBuilder and StringBuffer to provide us access to mutable string capabilities. Despite the fact that StringBuffer gives us strings that are secure to use with many threads, this additional feature slows it down. StringBuilder lacks thread safety and is absent from StringBuilder, but since it lacks this additional functionality, its implementation is quicker.

Only strings are used for I/O operations in Java programmes. As a result, strings are a crucial component of any Java application. Your name, roll number, address, and educational background are all specified using strings. Even measurable objects like 50 kg, 22 oz, 12 g, and many more might all be represented as strings.

This is the most fundamental class that Java offers. An example of a string might be apple, "pizza, or ''1234”. We may declare and define a string object in our applications thanks to the String class.

The unique quality of this class is that all objects produced within it are immutable (unchanged in nature). Every time the String object is changed, it produces a new object and assigns the modified value to it rather than changing the existing object. The distinction between a StringBuffer and a StringBuilder will also be covered.

Immutability is the property of an object that forbids modification after creation. Anyone who is familiar with programming could find this attribute boring. But did you know that James Gosling, the man behind Java, said as much?

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What Is a String Buffer?

Unlike the immutable String class, the class StringBuffer is changeable. A StringBuffer class's capacity and character string. Dynamic changes can be made to StringBuffer. a changeable, thread-safe string of characters. A string buffer is similar to a string but allows for modification. It always includes a specific character sequence, but by calling specific methods, the length and content of the sequence may be altered. The usage of string buffers by many threads is secure. Sync is supported by StringBuffer. This indicates that no more than one thread may simultaneously call a StringBuffer method.

It uses an asynchronous StringBuilder. This suggests that many threads may call StringBuilder's methods at once.

The variable name for the StringBuffer is set to new StringBuffer("String sequence");

StringBuffer Example

public class "StringBuffer" Example public static void main(String[] args) 

System. out.println("StringBufferExample" +buffer); public class StringBufferExample; public static void main(String[] args); StringBuffer buffer=new StringBuffer("Hi"); buffer.append("Java 8");

What Is a String Builder?

A changeable string of characters is represented by Java's StringBuilder. The StringBuilder class offers a substitute for the String Class in Java since it constructs a changeable sequence of characters instead of an immutable one as the String Class does. An asynchronous string builder is used. This implies that many threads may simultaneously invoke StringBuilder's functions.

StringBuilder is significantly quicker than StringBuffer since there isn't a preliminary check for many threads.

The functions of the StringBuilder and StringBuffer classes are extremely similar since they both create changeable sequences of characters as an alternative to the String class. However, synchronization is where the StringBuilder class and StringBuffer class diverge.

A changeable string of characters is represented by the Java class StringBuilder. 

The StringBuilder class offers a substitute for the String Class in Java since it constructs a changeable sequence of characters instead of an immutable one as the String Class does.

Contrary to the StringBuffer class, the StringBuilder class does not ensure synchronization. 

As a result, this class is intended to be utilized in areas where a single thread previously used the StringBuffer as a drop-in replacement (as is generally the case). It is advised to use this class instead of StringBuffer whenever feasible because it will typically be quicker in most implementations. StringBuilder instances should not be used by multiple threads.

StringBuilder Example

StringBuilder(): Creates a string builder with a starting capacity of 16 characters and no characters.

StringBuilder(int capacity): creates a string builder with an initial capacity determined by the capacity parameter and no characters in it.

Creates a string builder using the same characters as the supplied CharSequence using the StringBuilder(CharSequence seq) function.

StringBuilder(String str): Creates a string builder with the specified string's contents as its initial value.

In this example, we'll make a boolean variable with a starting value and a StringBuilder with a starting string literal. The boolean value will then be appended to the StringBuilder using the append() function.

System.out.println("StringBuilderExample" +builder); public class StringBuilderExample public static void main(String[] args) StringBuilder builder=new StringBuilder("Hi"); builder.append("Java 8");

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Difference Between String Buffer and String Builder

Both the StringBuilder and the StringBuffer are mutable classes that may be used to perform operations on string objects, including string concatenation, string reversal, and more. We may alter strings without making a new object out of the string. String builders are not thread-safe, although a string buffer is. It is, therefore, quicker than a string buffer. The StringBuffer or StringBuilder class is used internally by the StringConcat + operation. Here are the variations.

String Buffer

  • Basic: StringBuffer was first made available with Java's first release.
  • Synchronized: It is coordinated.
  • Performance: The thread is secure. Because numerous threads are unable to be accessed at once, it is sluggish.
  • Mutable: It can change. Strings can be changed without the creation of an object.
  • Storage: Heap

String Builder

  • Basic: It debuted with Java 5.
  • Synchronized: No synchronization exists.
  • Performance: It is quicker than String Buffer since it is not thread-safe.
  • Mutable: It can also change.
  • Storage: Heap

System.out.println("StringBuilderExample" +builder); public class StringBuilderExample public static void main(String[] args) StringBuilder builder=new StringBuilder("Hi"); builder.append("Java 8");

Implementation of StringBuffer and StringBuilder Classes in Java

In contrast to Java's String class, StringBuffer and StringBuilder are both mutable classes. The StringBuilder class and the StringBuffer class have the same API. The sole distinction is that whereas StringBuilder is neither synchronized nor thread-safe, StringBuffer is. In situations when thread safety is not necessary, the StringBuilder class was introduced in Java 1.5 and is meant to be a drop-in replacement for the StringBuffer class.

Performance Test of StringBuffer and StringBuilder

The StringBuilder class is recommended by the Java documentation instead of StringBuffer. This is because StringBuilder, which is not synchronized, is quicker than StringBuffer. To give an example, have a look at the performance benchmark test below, which measures how long StringBuffer and StringBuilder objects take to respond to repeated requests to the append() method. 

The application below demonstrates the speed advantage of the StringBuilder Class over the StringBuffer Class. Both of these classes have been used with an object that contains the string "Scaler." Then, after repeatedly adding a random string, we measure how long each string took to complete the identical task.

Because StringBuffer methods are synchronized whereas StringBuilder methods are not, there is a speed difference. StringBuffer is more secure to use than StringBuilder, but it is also slower due to the additional synchronization mechanisms.

Conversion From StringBuffer to StringBuilder

The StringBuffer cannot be changed into the StringBuilder directly. First, we must use the built-in function toString() { [native code] } to transform the StringBuffer into a String object (). We can easily create a StringBuilder by utilizing the class' function Object() { [native code] } after converting it to a string object.

As seen by the benchmark test mentioned above, the time consumed by the StringBuffer class is twice as long as that of the StringBuilder class. As seen by the benchmark test mentioned above. The thread safety offered by the StringBuffer class comes at a performance penalty. Use StringBuilder over StringBuffer if thread safety is not necessary. Only use StringBuffer when thread safety is necessary.

The StringBuilder cannot be converted directly to the StringBuffer, much like the conversion described before. First, we must use the built-in function toString() [native code] 

to convert the StringBuilder to a String object (). Now we can use the function Object() [native code] to create a StringBuilder.

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Hope this article was able to clear out the key differences between Stringbuffer and StringBuilder. If you are looking to further enhance your software development skills, we would highly recommend Simplilearn’s Post Graduate Program in Full Stack Web Development. This course, designed in collaboration with Caltech CTME can give you access to the relevant skills and make you job-ready in a quick time.

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