Spring Framework example source code file (FileSystemResource.java)

This example Spring Framework source code file (FileSystemResource.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

abstractresource, file, file, filesystemresource, filesystemresource, inputstream, io, ioexception, ioexception, net, network, path, resource, string, string, uri, url

The Spring Framework FileSystemResource.java source code

/*
 * Copyright 2002-2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.core.io;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.net.URL;

import org.springframework.util.Assert;
import org.springframework.util.StringUtils;

/**
 * {@link Resource} implementation for <code>java.io.File handles.
 * Obviously supports resolution as File, and also as URL.
 *
 * @author Juergen Hoeller
 * @since 28.12.2003
 * @see java.io.File
 */
public class FileSystemResource extends AbstractResource {

	private final File file;

	private final String path;


	/**
	 * Create a new FileSystemResource from a File handle.
	 * <p>Note: When building relative resources via {@link #createRelative},
	 * the relative path will apply <i>at the same directory level:
	 * e.g. new File("C:/dir1"), relative path "dir2" -> "C:/dir2"!
	 * If you prefer to have relative paths built underneath the given root
	 * directory, use the {@link #FileSystemResource(String) constructor with a file path}
	 * to append a trailing slash to the root path: "C:/dir1/", which
	 * indicates this directory as root for all relative paths.
	 * @param file a File handle
	 */
	public FileSystemResource(File file) {
		Assert.notNull(file, "File must not be null");
		this.file = file;
		this.path = StringUtils.cleanPath(file.getPath());
	}

	/**
	 * Create a new FileSystemResource from a file path.
	 * <p>Note: When building relative resources via {@link #createRelative},
	 * it makes a difference whether the specified resource base path here
	 * ends with a slash or not. In the case of "C:/dir1/", relative paths
	 * will be built underneath that root: e.g. relative path "dir2" ->
	 * "C:/dir1/dir2". In the case of "C:/dir1", relative paths will apply
	 * at the same directory level: relative path "dir2" -> "C:/dir2".
	 * @param path a file path
	 */
	public FileSystemResource(String path) {
		Assert.notNull(path, "Path must not be null");
		this.file = new File(path);
		this.path = StringUtils.cleanPath(path);
	}

	/**
	 * Return the file path for this resource.
	 */
	public final String getPath() {
		return this.path;
	}


	/**
	 * This implementation returns whether the underlying file exists.
	 * @see java.io.File#exists()
	 */
	public boolean exists() {
		return this.file.exists();
	}

	/**
	 * This implementation checks whether the underlying file is marked as readable
	 * (and corresponds to an actual file with content, not to a directory).
	 * @see java.io.File#canRead()
	 * @see java.io.File#isDirectory()
	 */
	public boolean isReadable() {
		return (this.file.canRead() && !this.file.isDirectory());
	}

	/**
	 * This implementation opens a FileInputStream for the underlying file.
	 * @see java.io.FileInputStream
	 */
	public InputStream getInputStream() throws IOException {
		return new FileInputStream(this.file);
	}

	/**
	 * This implementation returns a URL for the underlying file.
	 * @see java.io.File#toURI()
	 */
	public URL getURL() throws IOException {
		return this.file.toURI().toURL();
	}

	/**
	 * This implementation returns a URI for the underlying file.
	 * @see java.io.File#toURI()
	 */
	public URI getURI() throws IOException {
		return this.file.toURI();
	}

	/**
	 * This implementation returns the underlying File reference.
	 */
	public File getFile() {
		return this.file;
	}

	/**
	 * This implementation creates a FileSystemResource, applying the given path
	 * relative to the path of the underlying file of this resource descriptor.
	 * @see org.springframework.util.StringUtils#applyRelativePath(String, String)
	 */
	public Resource createRelative(String relativePath) {
		String pathToUse = StringUtils.applyRelativePath(this.path, relativePath);
		return new FileSystemResource(pathToUse);
	}

	/**
	 * This implementation returns the name of the file.
	 * @see java.io.File#getName()
	 */
	public String getFilename() {
		return this.file.getName();
	}

	/**
	 * This implementation returns a description that includes the absolute
	 * path of the file.
	 * @see java.io.File#getAbsolutePath()
	 */
	public String getDescription() {
		return "file [" + this.file.getAbsolutePath() + "]";
	}


	/**
	 * This implementation compares the underlying File references.
	 */
	public boolean equals(Object obj) {
		return (obj == this ||
		    (obj instanceof FileSystemResource && this.path.equals(((FileSystemResource) obj).path)));
	}

	/**
	 * This implementation returns the hash code of the underlying File reference.
	 */
	public int hashCode() {
		return this.path.hashCode();
	}

}