Java get file extension

In this post, we will see how to get extension of file in java.

As java.io.File does not provide any direct method for getting extension of file. This is used when you want to process file differently on the basis of its extension. I have worked on a project where I required this utility method.

There are two simple way to get it.

Table of Contents

Using simple String handling program

Create a simple java class named GetExtensionOfFileMain.java

When you run above program, you will get following output:

File extension for Countries.xlsx is xlsx
File extension for Captial.csv is csv
File extension for src/main/resources is

As you can see, by using [String’s contains()](https://java2blog.com/java-string-contains-ignorecase/ “String’s contains()”) and [lastIndexOf()](https://java2blog.com/java-string-lastindexof-example/ “lastIndexOf()”), we are able to get extension of file in java.

Using Apache io

You need to download Apcahe io jar and put it to the classpath.
After doing above steps, you just need to call FilenameUtils.getExtension() to retrieve extension of file in java.

When you run above program, you will get foloowing output:

File extension for Countries.xlsx is xlsx
File extension for Captial.csv is csv
File extension for src/main/resources is

That’s all about java get file extension.

Was this post helpful?

Related Posts

  • Convert OutputStream to byte array in java
    16 February

    Convert Outputstream to Byte Array in Java

    Table of ContentsConvert OutputStream to Byte array in JavaConvert OutputStream to ByteBuffer in JavaWas this post helpful? In this post, we will see how to convert OutputStream to Byte array in Java. Convert OutputStream to Byte array in Java Here are steps to convert OutputStream to Byte array in java. Create instance of ByteArrayOutputStream baos […]

  • 27 December

    How to get current working directory in java

    Learn about how to get current working directory in java using different ways

  • 08 August

    Difference between Scanner and BufferReader in java

    Table of ContentsIntroductionScannerBufferedReaderDifference between Scanner and BufferedReaderWas this post helpful? In this post, we will see difference between Scanner and BufferReader in java. Java has two classes that have been used for reading files for a very long time. These two classes are Scanner and BufferedReader. In this post, we are going to find major […]

  • 29 March

    Read UTF-8 Encoded Data in java

    Table of ContentsUsing Files’s newBufferedReader()Using BufferedReaderUsing DataInputStream’s readUTF() method Was this post helpful? In this post, we will see how to read UTF-8 Encoded Data. Sometimes, we have to deal with UTF-8 Encoded Data in our application. It may be due localization or may be processing data from user input. There are multiple ways to […]

  • 29 March

    Write UTF-8 Encoded Data in java

    Table of ContentsUsing Files’s newBufferWriter()Using BufferedWriterUsing DataOutputStream’s writeUTF() method Was this post helpful? In this post, we will see how to write UTF-8 Encoded Data. Sometimes, we have to deal with UTF-8 Encoded Data in our application. It may be due localization or may be processing data from user input. We will use Hindi language […]

  • 15 March

    Java read file line by line

    Table of ContentsJava 8 StreamsUsing BufferReaderUsing ScannerUsing FilesUsing RandomAccessFileUsing Apache CommonsWas this post helpful? In this post, we will see different ways to read file line by line in java. Sometimes, we need to read file line by line to a String, and process it. Here are different ways to read file line by line […]

Leave a Reply

Your email address will not be published.

Subscribe to our newletter

Get quality tutorials to your inbox. Subscribe now.