/*
* 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.ambari.logfeeder.input.reader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.zip.GZIPInputStream;
import org.apache.log4j.Logger;
class GZIPReader extends InputStreamReader {
private static final Logger LOG = Logger.getLogger(GZIPReader.class);
GZIPReader(String fileName) throws FileNotFoundException {
super(getStream(fileName));
LOG.info("Created GZIPReader for file : " + fileName);
}
private static InputStream getStream(String fileName) {
InputStream gzipStream = null;
InputStream fileStream = null;
try {
fileStream = new FileInputStream(fileName);
gzipStream = new GZIPInputStream(fileStream);
} catch (Exception e) {
LOG.error(e, e.getCause());
}
return gzipStream;
}
/**
* validating file based on magic number
*/
static boolean isValidFile(String fileName) {
// TODO make it generic and put in factory itself
try (InputStream is = new FileInputStream(fileName)) {
byte[] signature = new byte[2];
int nread = is.read(signature); // read the gzip signature
return nread == 2 && signature[0] == (byte) 0x1f && signature[1] == (byte) 0x8b;
} catch (IOException e) {
return false;
}
}
}