Java StringBuilder Made Easy: How to Use StringBuilder for Efficient String Manipulation | Tutorial

In this example, we create a StringBuilder object called sb and use its append method to concatenate the strings "Hello" and "world!" with a space in between.

After we have finished adding all the strings, we call the toString method to get the final string, which we assign to a variable called result. Finally, we print the value of result to the console, which should output "Hello world!".

You can use StringBuilder in this way to concatenate any number of strings in Java, which can be useful for generating dynamic strings, such as for generating a report or formatting output.

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