DefaultFileSystem.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.commons.configuration2.io;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import org.apache.commons.configuration2.ex.ConfigurationException;
/**
* FileSystem that uses java.io.File or HttpClient.
*
* @since 1.7
*/
public class DefaultFileSystem extends FileSystem {
/**
* Wraps the output stream so errors can be detected in the HTTP response.
*
* @since 1.7
*/
private static final class HttpOutputStream extends VerifiableOutputStream {
/** The wrapped OutputStream */
private final OutputStream stream;
/** The HttpURLConnection */
private final HttpURLConnection connection;
public HttpOutputStream(final OutputStream stream, final HttpURLConnection connection) {
this.stream = stream;
this.connection = connection;
}
@Override
public void close() throws IOException {
stream.close();
}
@Override
public void flush() throws IOException {
stream.flush();
}
@Override
public String toString() {
return stream.toString();
}
@Override
public void verify() throws IOException {
if (connection.getResponseCode() >= HttpURLConnection.HTTP_BAD_REQUEST) {
throw new IOException("HTTP Error " + connection.getResponseCode() + " " + connection.getResponseMessage());
}
}
@Override
public void write(final byte[] bytes) throws IOException {
stream.write(bytes);
}
@Override
public void write(final byte[] bytes, final int i, final int i1) throws IOException {
stream.write(bytes, i, i1);
}
@Override
public void write(final int i) throws IOException {
stream.write(i);
}
}
/**
* Create the path to the specified file.
*
* @param file the target file
* @throws ConfigurationException if the path cannot be created
*/
private void createPath(final File file) throws ConfigurationException {
// create the path to the file if the file doesn't exist
if (file != null && !file.exists()) {
final File parent = file.getParentFile();
if (parent != null && !parent.exists() && !parent.mkdirs()) {
throw new ConfigurationException("Cannot create path: " + parent);
}
}
}
@Override
public String getBasePath(final String path) {
final URL url;
try {
url = getURL(null, path);
return FileLocatorUtils.getBasePath(url);
} catch (final Exception e) {
return null;
}
}
@Override
public String getFileName(final String path) {
final URL url;
try {
url = getURL(null, path);
return FileLocatorUtils.getFileName(url);
} catch (final Exception e) {
return null;
}
}
@Override
public InputStream getInputStream(final URL url) throws ConfigurationException {
return getInputStream(url, null);
}
@Override
public InputStream getInputStream(final URL url, final URLConnectionOptions urlConnectionOptions) throws ConfigurationException {
// throw an exception if the target URL is a directory
final File file = FileLocatorUtils.fileFromURL(url);
if (file != null && file.isDirectory()) {
throw new ConfigurationException("Cannot load a configuration from a directory");
}
try {
return urlConnectionOptions == null ? url.openStream() : urlConnectionOptions.openConnection(url).getInputStream();
} catch (final Exception e) {
throw new ConfigurationException("Unable to load the configuration from the URL " + url, e);
}
}
@Override
public OutputStream getOutputStream(final File file) throws ConfigurationException {
try {
// create the file if necessary
createPath(file);
return new FileOutputStream(file);
} catch (final FileNotFoundException e) {
throw new ConfigurationException("Unable to save to file " + file, e);
}
}
@Override
public OutputStream getOutputStream(final URL url) throws ConfigurationException {
// file URLs have to be converted to Files since FileURLConnection is
// read only (https://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4191800)
final File file = FileLocatorUtils.fileFromURL(url);
if (file != null) {
return getOutputStream(file);
}
// for non file URLs save through an URLConnection
OutputStream out;
try {
final URLConnection connection = url.openConnection();
connection.setDoOutput(true);
// use the PUT method for http URLs
if (connection instanceof HttpURLConnection) {
final HttpURLConnection conn = (HttpURLConnection) connection;
conn.setRequestMethod("PUT");
}
out = connection.getOutputStream();
// check the response code for http URLs and throw an exception if an error occurred
if (connection instanceof HttpURLConnection) {
out = new HttpOutputStream(out, (HttpURLConnection) connection);
}
return out;
} catch (final IOException e) {
throw new ConfigurationException("Could not save to URL " + url, e);
}
}
@Override
public String getPath(final File file, final URL url, final String basePath, final String fileName) {
String path = null;
// if resource was loaded from jar file may be null
if (file != null) {
path = file.getAbsolutePath();
}
// try to see if file was loaded from a jar
if (path == null) {
if (url != null) {
path = url.getPath();
} else {
try {
path = getURL(basePath, fileName).getPath();
} catch (final Exception e) {
// simply ignore it and return null
if (getLogger().isDebugEnabled()) {
getLogger().debug(String.format("Could not determine URL for " + "basePath = %s, fileName = %s: %s", basePath, fileName, e));
}
}
}
}
return path;
}
@Override
public URL getURL(final String basePath, final String file) throws MalformedURLException {
final File f = new File(file);
// already absolute?
if (f.isAbsolute()) {
return FileLocatorUtils.toURL(f);
}
try {
if (basePath == null) {
return new URL(file);
}
final URL base = new URL(basePath);
return new URL(base, file);
} catch (final MalformedURLException uex) {
return FileLocatorUtils.toURL(FileLocatorUtils.constructFile(basePath, file));
}
}
@Override
public URL locateFromURL(final String basePath, final String fileName) {
try {
final URL url;
if (basePath == null) {
return new URL(fileName);
// url = new URL(name);
}
final URL baseURL = new URL(basePath);
url = new URL(baseURL, fileName);
// check if the file exists
try (InputStream in = url.openStream()) {
// nothing
in.available();
}
return url;
} catch (final IOException e) {
if (getLogger().isDebugEnabled()) {
getLogger().debug("Could not locate file " + fileName + " at " + basePath + ": " + e.getMessage());
}
return null;
}
}
}