How to Remove Punctuation in a Java String

By Mike Wallace

Students of programming are often given interesting and educational challenges, such as removing all the punctuation in a string of text. This particular task requires the knowledge of string handling for a particular language. The Java language has robust string-handling facilities that make a task like this fairly simple, but also informative if you are new to Java. You can remove the punctuation from a string in Java with just a few lines of code.

Things You'll Need

  • Java Development Kit
  • Netbeans Bundle

Step 1

Load the NetBeans Java development environment by clicking on its icon. Choose "File/New Project" from the menu at the top of the page. Select "Java Application" to create a new source code file. The source code file only contains a main function, which is where you will put all your code.

Step 2

Create a string with a lot of unnecessary punctuation, like this: String str = "Punctuation: Removal; String.";

Step 3

Remove all of the punctuation by using a regular expression like this: str = str.replaceAll("[^A-Za-z0-9]", "");

Step 4

Print out the string like this: System.out.println(str);

Step 5

Press F6 to launch the program. The output looks like this:PunctuationRemovalString