lang/java/reef-common/src/main/java/org/apache/reef/runtime/common/evaluator/context/ContextClientCodeException.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
 *
 *   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.reef.runtime.common.evaluator.context;

import org.apache.reef.evaluator.context.parameters.ContextIdentifier;
import org.apache.reef.tang.Configuration;
import org.apache.reef.tang.Tang;
import org.apache.reef.tang.exceptions.InjectionException;
import org.apache.reef.util.Optional;

/**
 * Thrown when we encounter a problem with client code in a context.
 */
public final class ContextClientCodeException extends Exception {
  private final String contextID;
  private final Optional<String> parentID;

  /**
   * @param contextID the ID of the failed context.
   * @param parentID  the ID of the failed context's parent, if any.
   * @param message   the error message.
   * @param cause     the exception that caused the error.
   */
  public ContextClientCodeException(final String contextID,
                                    final Optional<String> parentID,
                                    final String message,
                                    final Throwable cause) {
    super("Failure in context '" + contextID + "': " + message, cause);
    this.contextID = contextID;
    this.parentID = parentID;
  }

  /**
   * Extracts a context id from the given configuration.
   *
   * @param c
   * @return the context id in the given configuration.
   * @throws RuntimeException if the configuration can't be parsed.
   */
  public static String getIdentifier(final Configuration c) {
    try {
      return Tang.Factory.getTang().newInjector(c).getNamedInstance(
          ContextIdentifier.class);
    } catch (final InjectionException e) {
      throw new RuntimeException("Unable to determine context identifier. Giving up.", e);
    }
  }

  /**
   * @return the ID of the failed context
   */
  public String getContextID() {
    return this.contextID;
  }

  /**
   * @return the ID of the failed context's parent, if any
   */
  public Optional<String> getParentID() {
    return this.parentID;
  }
}