In Java, both StringBuffer and StringBuilder classes are used to manipulate strings, but there is a key difference between them:
StringBuffer is a thread-safe class, while StringBuilder is not thread-safe. This means that StringBuffer can be used safely in a multi-threaded environment, where multiple threads may access and modify the same object simultaneously.
StringBuilder, on the other hand, should be used in a single-threaded environment or when the synchronization of StringBuffer is not required. Since it is not thread-safe, it is generally faster and more efficient than StringBuffer.
Both StringBuffer and StringBuilder are mutable, meaning that they can be modified after creation. They both have similar methods for appending, inserting, and deleting characters and substrings from a string.
Here is an example to demonstrate the usage of both classes:
StringBuffer sb = new StringBuffer(“Hello”);
sb.append(” World”); // sb = “Hello World”
sb.insert(6, “,”); // sb = “Hello, World”
sb.delete(5, 6); // sb = “Hello World”
StringBuilder sb2 = new StringBuilder(“Hello”);
sb2.append(” World”); // sb2 = “Hello World”
sb2.insert(6, “,”); // sb2 = “Hello, World”
sb2.delete(5, 6); // sb2 = “Hello World”
In summary, StringBuffer and StringBuilder are similar in functionality, but StringBuffer is thread-safe and StringBuilder is not. The choice of which one to use depends on the requirements of the application, such as whether thread safety is required or performance is a concern.