com.orientechnologies.orient.core.command.OCommandManager Maven / Gradle / Ivy

/*
  *
  *  *  Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
  *  *
  *  *  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.
  *  *
  *  * For more information: http://www.orientechnologies.com
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package com.orientechnologies.orient.core.command;

import com.orientechnologies.common.util.OCallable;
import com.orientechnologies.orient.core.command.script.OCommandExecutorScript;
import com.orientechnologies.orient.core.command.script.OCommandScript;
import com.orientechnologies.orient.core.exception.OCommandExecutionException;
import com.orientechnologies.orient.core.sql.OCommandExecutorSQLDelegate;
import com.orientechnologies.orient.core.sql.OCommandExecutorSQLResultsetDelegate;
import com.orientechnologies.orient.core.sql.OCommandSQL;
import com.orientechnologies.orient.core.sql.OCommandSQLResultset;
import com.orientechnologies.orient.core.sql.query.OSQLAsynchQuery;
import com.orientechnologies.orient.core.sql.query.OSQLSynchQuery;

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

public class OCommandManager {
  private static OCommandManager                                                   instance          = new OCommandManager();
  private Map>                            commandRequesters = new HashMap>();
  private Map, OCallable>  configCallbacks   = new HashMap, OCallable>();
  private Map, Class> commandReqExecMap = new HashMap, Class>();

  protected OCommandManager() {
    registerRequester("sql", OCommandSQL.class);
    registerRequester("script", OCommandScript.class);

    registerExecutor(OSQLAsynchQuery.class, OCommandExecutorSQLDelegate.class);
    registerExecutor(OSQLSynchQuery.class, OCommandExecutorSQLDelegate.class);
    registerExecutor(OCommandSQL.class, OCommandExecutorSQLDelegate.class);
    registerExecutor(OCommandSQLResultset.class, OCommandExecutorSQLResultsetDelegate.class);
    registerExecutor(OCommandScript.class, OCommandExecutorScript.class);
  }

  public static OCommandManager instance() {
    return instance;
  }

  public OCommandManager registerRequester(final String iType, final Class iRequest) {
    commandRequesters.put(iType, iRequest);
    return this;
  }

  public boolean existsRequester(final String iType) {
    return commandRequesters.containsKey(iType);
  }

  public OCommandRequest getRequester(final String iType) {
    final Class reqClass = commandRequesters.get(iType);

    if (reqClass == null)
      throw new IllegalArgumentException("Cannot find a command requester for type: " + iType);

    try {
      return reqClass.newInstance();
    } catch (Exception e) {
      throw new IllegalArgumentException("Cannot create the command requester of class " + reqClass + " for type: " + iType, e);
    }
  }

  public OCommandManager registerExecutor(final Class iRequest,
      final Class iExecutor, final OCallable iConfigCallback) {
    registerExecutor(iRequest, iExecutor);
    configCallbacks.put(iRequest, iConfigCallback);
    return this;
  }

  public OCommandManager registerExecutor(final Class iRequest,
      final Class iExecutor) {
    commandReqExecMap.put(iRequest, iExecutor);
    return this;
  }

  public OCommandManager unregisterExecutor(final Class iRequest) {
    commandReqExecMap.remove(iRequest);
    configCallbacks.remove(iRequest);
    return this;
  }

  public OCommandExecutor getExecutor(OCommandRequestInternal iCommand) {
    final Class executorClass = commandReqExecMap.get(iCommand.getClass());

    if (executorClass == null)
      throw new OCommandExecutorNotFoundException("Cannot find a command executor for the command request: " + iCommand);

    try {
      final OCommandExecutor exec = executorClass.newInstance();

      final OCallable callback = configCallbacks.get(iCommand.getClass());
      if (callback != null)
        callback.call(iCommand);

      return exec;

    } catch (Exception e) {
      throw new OCommandExecutionException("Cannot create the command executor of class " + executorClass
          + " for the command request: " + iCommand, e);
    }
  }
}