org.apache.hadoop.util.NativeCodeLoader Maven / Gradle / Ivy
/**
* 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.hadoop.util;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CommonConfigurationKeys;
/**
* A helper to load the native hadoop code i.e. libhadoop.so.
* This handles the fallback to either the bundled libhadoop-Linux-i386-32.so
* or the default java implementations where appropriate.
*
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
public class NativeCodeLoader {
private static final Log LOG =
LogFactory.getLog(NativeCodeLoader.class);
private static boolean nativeCodeLoaded = false;
static {
// Try to load native hadoop library and set fallback flag appropriately
if(LOG.isDebugEnabled()) {
LOG.debug("Trying to load the custom-built native-hadoop library...");
}
try {
System.loadLibrary("hadoop");
LOG.debug("Loaded the native-hadoop library");
nativeCodeLoaded = true;
} catch (Throwable t) {
// Ignore failure to load
if(LOG.isDebugEnabled()) {
LOG.debug("Failed to load native-hadoop with error: " + t);
LOG.debug("java.library.path=" +
System.getProperty("java.library.path"));
}
}
if (!nativeCodeLoaded) {
LOG.warn("Unable to load native-hadoop library for your platform... " +
"using builtin-java classes where applicable");
}
}
/**
* Check if native-hadoop code is loaded for this platform.
*
* @return true if native-hadoop is loaded,
* else false
*/
public static boolean isNativeCodeLoaded() {
return nativeCodeLoaded;
}
/**
* Returns true only if this build was compiled with support for snappy.
*/
public static native boolean buildSupportsSnappy();
/**
* Return if native hadoop libraries, if present, can be used for this job.
* @param conf configuration
*
* @return true if native hadoop libraries, if present, can be
* used for this job; false otherwise.
*/
public boolean getLoadNativeLibraries(Configuration conf) {
return conf.getBoolean(CommonConfigurationKeys.IO_NATIVE_LIB_AVAILABLE_KEY,
CommonConfigurationKeys.IO_NATIVE_LIB_AVAILABLE_DEFAULT);
}
/**
* Set if native hadoop libraries, if present, can be used for this job.
*
* @param conf configuration
* @param loadNativeLibraries can native hadoop libraries be loaded
*/
public void setLoadNativeLibraries(Configuration conf,
boolean loadNativeLibraries) {
conf.setBoolean(CommonConfigurationKeys.IO_NATIVE_LIB_AVAILABLE_KEY,
loadNativeLibraries);
}
}