What is the Difference Between `getResource` and `getResourceAsStream` in Java?

In Java, both getResource and getResourceAsStream methods are used to access resources within your application. However, they differ in the type of data they return and how they handle the resource.

getResource

• Returns: A URL object representing the location of the resource.
• Purpose: To obtain the location of a resource, allowing you to manipulate it using the URL object.
• Usage: You can use the returned URL to:
  • Open a connection to the resource using URL.openStream().
  • Extract the resource's path using URL.getPath().
  • Obtain the resource's protocol using URL.getProtocol().

Example:

URL resourceURL = getClass().getResource("my_file.txt");
if (resourceURL != null) {
    // Access the resource using the URL object
    InputStream inputStream = resourceURL.openStream();
    // ... process the resource ...
} else {
    System.err.println("Resource not found: my_file.txt");
}

getResourceAsStream

• Returns: An InputStream object directly representing the content of the resource.
• Purpose: To directly access the content of a resource as a stream of bytes.
• Usage: Suitable for reading the content of a resource, such as text files, images, or other binary data.

Example:

InputStream inputStream = getClass().getResourceAsStream("my_file.txt");
if (inputStream != null) {
    // Read the resource content directly
    // ... process the resource ...
} else {
    System.err.println("Resource not found: my_file.txt");
}

Choosing the Right Method

• getResource: Use when you need to manipulate the resource's location or perform operations on the URL object itself.
• getResourceAsStream: Use when you want to directly access the content of the resource as a stream of bytes.

Conclusion

In summary, getResource provides a URL object representing the resource's location, while getResourceAsStream directly returns an InputStream for reading the resource's content. Choose the method that best suits your specific needs based on whether you want to manipulate the resource's URL or access its data directly.