AbstractShardOperation.java

/**
 * Copyright 2008 the original author or authors.
 *
 * Licensed 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 net.sf.katta.operation.node;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import net.sf.katta.node.NodeContext;

import org.I0Itec.zkclient.ExceptionUtil;
import org.apache.log4j.Logger;

public abstract class AbstractShardOperation implements NodeOperation {

  private static final long serialVersionUID = 1L;
  private final static Logger LOG = Logger.getLogger(AbstractShardOperation.class);

  private Map<String, String> _shardPathesByShardNames = new HashMap<String, String>(3);

  public Set<String> getShardNames() {
    return _shardPathesByShardNames.keySet();
  }

  public String getShardPath(String shardName) {
    return _shardPathesByShardNames.get(shardName);
  }

  public void addShard(String shardName, String shardPath) {
    _shardPathesByShardNames.put(shardName, shardPath);
  }

  public void addShard(String shardName) {
    _shardPathesByShardNames.put(shardName, null);
  }

  @Override
  public final DeployResult execute(NodeContext context) throws InterruptedException {
    DeployResult result = new DeployResult(context.getNode().getName());
    for (String shardName : getShardNames()) {
      try {
        LOG.info(getOperationName() + " shard '" + shardName + "'");
        execute(context, shardName, result);
      } catch (Exception e) {
        ExceptionUtil.rethrowInterruptedException(e);
        LOG.error("failed to " + getOperationName() + " shard '" + shardName + "' on node '"
                + context.getNode().getName() + "'", e);
        result.addShardException(shardName, e);
        onException(context, shardName, e);
      }
    }
    return result;
  }

  protected abstract String getOperationName();

  protected abstract void execute(NodeContext context, String shardName, DeployResult result) throws Exception;

  protected abstract void onException(NodeContext context, String shardName, Exception e);

  protected void publishShard(String shardName, NodeContext context) {
    LOG.info("publish shard '" + shardName + "'");
    context.getProtocol().publishShard(context.getNode(), shardName);
  }

  @Override
  public final String toString() {
    return getClass().getSimpleName() + ":" + Integer.toHexString(hashCode()) + ":" + getShardNames();
  }

}