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GATE - general achitecture for text engineering - is open source software capable of solving almost any text processing problem. This artifact enables you to embed the core GATE Embedded with its essential dependencies. You will able to use the GATE Embedded API and load and store GATE XML documents. This artifact is the perfect dependency for CREOLE plugins or for applications that need to customize the GATE dependencies due to confict with their own dependencies or for lower footprint.

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/*
 *  Copyright (c) 1995-2012, The University of Sheffield. See the file
 *  COPYRIGHT.txt in the software or at http://gate.ac.uk/gate/COPYRIGHT.txt
 *
 *  This file is part of GATE (see http://gate.ac.uk/), and is free
 *  software, licenced under the GNU Library General Public License,
 *  Version 2, June 1991 (in the distribution as file licence.html,
 *  and also available at http://gate.ac.uk/gate/licence.html).
 *
 *  Valentin Tablan 26/10/2001
 *
 *  $Id: DSPersistence.java 18176 2014-07-11 15:45:13Z johann_p $
 *
 */
package gate.util.persistence;

import java.net.MalformedURLException;
import java.util.Iterator;

import gate.*;
import gate.creole.ResourceInstantiationException;
import gate.persist.PersistenceException;
import java.net.URL;

public class DSPersistence extends AbstractPersistence{


  /**
   * Populates this Persistence with the data that needs to be stored from the
   * original source object.
   */
  @Override
  public void extractDataFromSource(Object source)throws PersistenceException{
    //check input
    if(! (source instanceof DataStore)){
      throw new UnsupportedOperationException(
                getClass().getName() + " can only be used for " +
                DataStore.class.getName() +
                " objects!\n" + source.getClass().getName() +
                " is not a " + DataStore.class.getName());
    }

    DataStore ds = (DataStore)source;
    className = ds.getClass().getName();
    storageUrlString = ds.getStorageUrl();
    try {
      storageUrl = PersistenceManager.getPersistentRepresentation(
        new URL(storageUrlString));
    } catch(MalformedURLException e) {
      // ignore and just stay with storageUrlString
    }
  }

  /**
   * Creates a new object from the data contained. This new object is supposed
   * to be a copy for the original object used as source for data extraction.
   */
  @Override
  public Object createObject()throws PersistenceException,
                                     ResourceInstantiationException{
    if(storageUrl != null) {
      storageUrlString =
        ((URL)PersistenceManager.getTransientRepresentation(storageUrl))
          .toExternalForm();
    }

    //check if the same datastore is not already open
    Iterator dsIter = Gate.getDataStoreRegister().iterator();
    while(dsIter.hasNext()){
      DataStore aDS = dsIter.next();
      if(aDS.getStorageUrl().equals(storageUrlString)) {
        return aDS;
      }
    }
    //if we got this far, then it's a new datastore that needs opening
    return Factory.openDataStore(className, storageUrlString);
  }
 
  protected String className;
  protected String storageUrlString;
  protected Object storageUrl;
  static final long serialVersionUID = 5952924943977701708L;
}