/*
* Copyright 2013 (c) MuleSoft, Inc.
*
* 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.raml.parser.utils;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import org.apache.commons.io.IOUtils;
import org.mozilla.universalchardet.UniversalDetector;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class StreamUtils
{
private static final Logger LOGGER = LoggerFactory.getLogger(StreamUtils.class);
private static final String RAML_PARSER_ENCODING = "raml.parser.encoding";
private static String getDefaultEncoding()
{
return System.getProperty(RAML_PARSER_ENCODING, "UTF-8");
}
public static Reader reader(InputStream stream)
{
try
{
byte[] content = IOUtils.toByteArray(stream);
return new InputStreamReader(new ByteArrayInputStream(content), detectEncoding(content));
}
catch (IOException e)
{
throw new RuntimeException(e);
}
finally
{
IOUtils.closeQuietly(stream);
}
}
public static String toString(InputStream stream)
{
try
{
byte[] content = IOUtils.toByteArray(stream);
String encoding = detectEncoding(content);
return new String(trimBom(content), encoding);
}
catch (IOException e)
{
throw new RuntimeException(e);
}
}
private static byte[] trimBom(byte[] content)
{
int bomSize = 0;
if (content.length > 4)
{
//check for UTF_32BE and UTF_32LE BOMs
if (content[0] == 0x00 && content[1] == 0x00 && content[2] == (byte) 0xFE && content[3] == (byte) 0xFF ||
content[0] == (byte) 0xFF && content[1] == (byte) 0xFE && content[2] == 0x00 && content[3] == 0x00)
{
bomSize = 4;
}
}
if (content.length > 3 && bomSize == 0)
{
//check for UTF-8 BOM
if (content[0] == (byte) 0xEF && content[1] == (byte) 0xBB && content[2] == (byte) 0xBF)
{
bomSize = 3;
}
}
if (content.length > 2 && bomSize == 0)
{
//check for UTF_16BE and UTF_16LE BOMs
if (content[0] == (byte) 0xFE && content[1] == (byte) 0xFF || content[0] == (byte) 0xFF && content[1] == (byte) 0xFE)
{
bomSize = 2;
}
}
if (bomSize > 0)
{
LOGGER.debug(String.format("Trimming %s-byte BOM\n", bomSize));
int trimmedSize = content.length - bomSize;
byte[] trimmedArray = new byte[trimmedSize];
System.arraycopy(content, bomSize, trimmedArray, 0, trimmedSize);
return trimmedArray;
}
return content;
}
private static String detectEncoding(byte[] content)
{
UniversalDetector detector = new UniversalDetector(null);
detector.handleData(content, 0, content.length);
detector.dataEnd();
String encoding = detector.getDetectedCharset();
if (encoding != null)
{
LOGGER.debug(String.format("Detected encoding: %s\n", encoding));
}
else
{
encoding = getDefaultEncoding();
LOGGER.debug(String.format("No encoding detected, using default: %s\n", encoding));
}
detector.reset();
return encoding;
}
}