Spring Resource Interface, Resource Abstraction and Implementations

Resource #

Spring provides additional implementations to overcome the limitations of java.net.URL (e.g., accessing within the classpath or relative paths).

Resource Interface #

public interface Resource extends InutStreamSource {
	boolean exists();
	boolean isReadable();
	boolean isOpen();
	boolean isFile();

	URL getURL() throws IOException;
	URI getURI() throws IOEXception;
	File getFile() throws IOException;
	ReadableByteChannel readableChannel() throws IOException;
	
	long contentLength() throws IOException;
	long lastModified() throws IOException;
	
	Resouce createRelative(String relativaPath) throws IOException;
	String getFilename();
	String getDescription();
}

Resource Implementations #

UrlResource #

Reads resources based on a URL.

Supported protocols include http, https, ftp, file, jar.

ClassPathResource #

When the supported prefix is classpath:, it reads resources based on the classpath.

FileSystemResource #

Reads based on the file system.

ServeltContextResource #

Finds resources by relative path from the web application root.

InputStreamResource, ByteArrayResource #

As the name suggests, these are implementations for obtaining InputStream and ByteArrayInput.