org.apache.hadoop.util.NativeCodeLoader.java Source code

Introduction

Here is the source code for org.apache.hadoop.util.NativeCodeLoader.java

Source

/**
 * 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.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 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 final class NativeCodeLoader {

    private static final Logger LOG = LoggerFactory.getLogger(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");
        }
    }

    private NativeCodeLoader() {
    }

    /**
     * Check if native-hadoop code is loaded for this platform.
     * 
     * @return <code>true</code> if native-hadoop is loaded, 
     *         else <code>false</code>
     */
    public static boolean isNativeCodeLoaded() {
        return nativeCodeLoaded;
    }

    /**
     * Returns true only if this build was compiled with support for snappy.
     */
    public static native boolean buildSupportsSnappy();

    /**
     * Returns true only if this build was compiled with support for ISA-L.
     */
    public static native boolean buildSupportsIsal();

    /**
    * Returns true only if this build was compiled with support for ZStandard.
     */
    public static native boolean buildSupportsZstd();

    /**
     * Returns true only if this build was compiled with support for openssl.
     */
    public static native boolean buildSupportsOpenssl();

    public static native String getLibraryName();

}