/*
* 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.tomcat.util.http.fileupload.util;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.tomcat.util.http.fileupload.IOUtils;
import org.apache.tomcat.util.http.fileupload.InvalidFileNameException;
/**
* Utility class for working with streams.
*/
public final class Streams {
/**
* Private constructor, to prevent instantiation.
* This class has only static methods.
*/
private Streams() {
// Does nothing
}
/**
* Default buffer size for use in
* {@link #copy(InputStream, OutputStream, boolean)}.
*/
private static final int DEFAULT_BUFFER_SIZE = 8192;
/**
* Copies the contents of the given {@link InputStream}
* to the given {@link OutputStream}. Shortcut for
* <pre>
* copy(pInputStream, pOutputStream, new byte[8192]);
* </pre>
*
* @param inputStream The input stream, which is being read.
* It is guaranteed, that {@link InputStream#close()} is called
* on the stream.
* @param outputStream The output stream, to which data should
* be written. May be null, in which case the input streams
* contents are simply discarded.
* @param closeOutputStream True guarantees, that {@link OutputStream#close()}
* is called on the stream. False indicates, that only
* {@link OutputStream#flush()} should be called finally.
*
* @return Number of bytes, which have been copied.
* @throws IOException An I/O error occurred.
*/
public static long copy(InputStream inputStream, OutputStream outputStream, boolean closeOutputStream)
throws IOException {
return copy(inputStream, outputStream, closeOutputStream, new byte[DEFAULT_BUFFER_SIZE]);
}
/**
* Copies the contents of the given {@link InputStream}
* to the given {@link OutputStream}.
*
* @param inputStream The input stream, which is being read.
* It is guaranteed, that {@link InputStream#close()} is called
* on the stream.
* @param outputStream The output stream, to which data should
* be written. May be null, in which case the input streams
* contents are simply discarded.
* @param closeOutputStream True guarantees, that {@link OutputStream#close()}
* is called on the stream. False indicates, that only
* {@link OutputStream#flush()} should be called finally.
* @param buffer Temporary buffer, which is to be used for
* copying data.
* @return Number of bytes, which have been copied.
* @throws IOException An I/O error occurred.
*/
public static long copy(InputStream inputStream,
OutputStream outputStream, boolean closeOutputStream,
byte[] buffer)
throws IOException {
OutputStream out = outputStream;
InputStream in = inputStream;
try {
long total = 0;
for (;;) {
int res = in.read(buffer);
if (res == -1) {
break;
}
if (res > 0) {
total += res;
if (out != null) {
out.write(buffer, 0, res);
}
}
}
if (out != null) {
if (closeOutputStream) {
out.close();
} else {
out.flush();
}
out = null;
}
in.close();
in = null;
return total;
} finally {
IOUtils.closeQuietly(in);
if (closeOutputStream) {
IOUtils.closeQuietly(out);
}
}
}
/**
* This convenience method allows to read a
* {@link org.apache.tomcat.util.http.fileupload.FileItemStream}'s
* content into a string. The platform's default character encoding
* is used for converting bytes into characters.
*
* @param inputStream The input stream to read.
* @see #asString(InputStream, String)
* @return The streams contents, as a string.
* @throws IOException An I/O error occurred.
*/
public static String asString(InputStream inputStream) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
copy(inputStream, baos, true);
return baos.toString();
}
/**
* This convenience method allows to read a
* {@link org.apache.tomcat.util.http.fileupload.FileItemStream}'s
* content into a string, using the given character encoding.
*
* @param inputStream The input stream to read.
* @param encoding The character encoding, typically "UTF-8".
* @see #asString(InputStream)
* @return The streams contents, as a string.
* @throws IOException An I/O error occurred.
*/
public static String asString(InputStream inputStream, String encoding) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
copy(inputStream, baos, true);
return baos.toString(encoding);
}
/**
* Checks, whether the given file name is valid in the sense,
* that it doesn't contain any NUL characters. If the file name
* is valid, it will be returned without any modifications. Otherwise,
* an {@link InvalidFileNameException} is raised.
*
* @param fileName The file name to check
* @return Unmodified file name, if valid.
* @throws InvalidFileNameException The file name was found to be invalid.
*/
public static String checkFileName(String fileName) {
if (fileName != null && fileName.indexOf('\u0000') != -1) {
// pFileName.replace("\u0000", "\\0")
final StringBuilder sb = new StringBuilder();
for (int i = 0; i < fileName.length(); i++) {
char c = fileName.charAt(i);
switch (c) {
case 0:
sb.append("\\0");
break;
default:
sb.append(c);
break;
}
}
throw new InvalidFileNameException(fileName,
"Invalid file name: " + sb);
}
return fileName;
}
}