hadoop CosNUtils 源码

haddop CosNUtils 代码

文件路径：/hadoop-cloud-storage-project/hadoop-cos/src/main/java/org/apache/hadoop/fs/cosn/CosNUtils.java

/**
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.fs.cosn;

import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.net.URI;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.qcloud.cos.auth.COSCredentialsProvider;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.cosn.auth.COSCredentialsProviderList;
import org.apache.hadoop.fs.cosn.auth.EnvironmentVariableCredentialsProvider;
import org.apache.hadoop.fs.cosn.auth.SimpleCredentialsProvider;

/**
 * Utility methods for CosN code.
 */
public final class CosNUtils {
  private static final Logger LOG = LoggerFactory.getLogger(CosNUtils.class);

  static final String INSTANTIATION_EXCEPTION
      = "instantiation exception";
  static final String NOT_COS_CREDENTIAL_PROVIDER
      = "is not cos credential provider";
  static final String ABSTRACT_CREDENTIAL_PROVIDER
      = "is abstract and therefore cannot be created";

  private CosNUtils() {
  }

  public static COSCredentialsProviderList createCosCredentialsProviderSet(
      URI uri,
      Configuration conf) throws IOException {
    COSCredentialsProviderList credentialProviderList =
        new COSCredentialsProviderList();

    Class<?>[] cosClasses = CosNUtils.loadCosProviderClasses(
        conf,
        CosNConfigKeys.COSN_CREDENTIALS_PROVIDER);
    if (0 == cosClasses.length) {
      credentialProviderList.add(
          new SimpleCredentialsProvider(uri, conf));
      credentialProviderList.add(
          new EnvironmentVariableCredentialsProvider(uri, conf));
    } else {
      for (Class<?> credClass : cosClasses) {
        credentialProviderList.add(createCOSCredentialProvider(uri, conf,
            credClass));
      }
    }

    return credentialProviderList;
  }

  public static Class<?>[] loadCosProviderClasses(
      Configuration conf,
      String key,
      Class<?>... defaultValue) throws IOException {
    try {
      return conf.getClasses(key, defaultValue);
    } catch (RuntimeException e) {
      Throwable c = e.getCause() != null ? e.getCause() : e;
      throw new IOException("From option " + key + ' ' + c, c);
    }
  }

  public static COSCredentialsProvider createCOSCredentialProvider(
      URI uri,
      Configuration conf,
      Class<?> credClass) throws IOException {
    COSCredentialsProvider credentialsProvider;
    if (!COSCredentialsProvider.class.isAssignableFrom(credClass)) {
      throw new IllegalArgumentException("class " + credClass + " " +
          NOT_COS_CREDENTIAL_PROVIDER);
    }
    if (Modifier.isAbstract(credClass.getModifiers())) {
      throw new IllegalArgumentException("class " + credClass + " " +
          ABSTRACT_CREDENTIAL_PROVIDER);
    }
    LOG.debug("Credential Provider class: " + credClass.getName());

    try {
      // new credClass()
      Constructor constructor = getConstructor(credClass);
      if (constructor != null) {
        credentialsProvider =
            (COSCredentialsProvider) constructor.newInstance();
        return credentialsProvider;
      }
      // new credClass(conf)
      constructor = getConstructor(credClass, Configuration.class);
      if (null != constructor) {
        credentialsProvider =
            (COSCredentialsProvider) constructor.newInstance(conf);
        return credentialsProvider;
      }

      // new credClass(uri, conf)
      constructor = getConstructor(credClass, URI.class,
          Configuration.class);
      if (null != constructor) {
        credentialsProvider =
            (COSCredentialsProvider) constructor.newInstance(uri,
                conf);
        return credentialsProvider;
      }

      Method factory = getFactoryMethod(credClass,
          COSCredentialsProvider.class, "getInstance");
      if (null != factory) {
        credentialsProvider = (COSCredentialsProvider) factory.invoke(null);
        return credentialsProvider;
      }

      throw new IllegalArgumentException(
          "Not supported constructor or factory method found"
      );

    } catch (IllegalAccessException e) {
      throw new IOException(
          credClass.getName() + " " + INSTANTIATION_EXCEPTION + ": " + e, e);
    } catch (InstantiationException e) {
      throw new IOException(
          credClass.getName() + " " + INSTANTIATION_EXCEPTION + ": " + e, e);
    } catch (InvocationTargetException e) {
      Throwable targetException = e.getTargetException();
      if (targetException == null) {
        targetException = e;
      }
      throw new IOException(
          credClass.getName() + " " + INSTANTIATION_EXCEPTION + ": "
              + targetException, targetException);
    }
  }

  private static Constructor<?> getConstructor(Class<?> cl, Class<?>... args) {
    try {
      Constructor constructor = cl.getDeclaredConstructor(args);
      return Modifier.isPublic(constructor.getModifiers()) ? constructor : null;
    } catch (NoSuchMethodException e) {
      return null;
    }
  }

  private static Method getFactoryMethod(
      Class<?> cl, Class<?> returnType, String methodName) {
    try {
      Method m = cl.getDeclaredMethod(methodName);
      if (Modifier.isPublic(m.getModifiers())
          && Modifier.isStatic(m.getModifiers())
          && returnType.isAssignableFrom(m.getReturnType())) {
        return m;
      } else {
        return null;
      }
    } catch (NoSuchMethodException e) {
      return null;
    }
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop BufferPool 源码

hadoop ByteBufferInputStream 源码

hadoop ByteBufferOutputStream 源码

hadoop ByteBufferWrapper 源码

hadoop Constants 源码

hadoop CosN 源码

hadoop CosNConfigKeys 源码

hadoop CosNCopyFileContext 源码

hadoop CosNCopyFileTask 源码

hadoop CosNFileReadTask 源码