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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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/*
 *  GateAwareObjectInputStream.java
 *
 *  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).
 *
 *  Ian Roberts, 04/Apr/2007
 *
 *  $Id: GateAwareObjectInputStream.java 15333 2012-02-07 13:18:33Z ian_roberts $
 */

package gate.persist;

import java.io.*;
import java.lang.reflect.Proxy;

import gate.Gate;

/**
 * An ObjectInputStream that attempts to resolve the classes of objects
 * loaded from the stream via the GateClassLoader if they cannot be
 * found by the usual means. This allows LRs to be loaded successfully
 * from a serial datastore when they have features (or annotations with
 * features) whose class is defined in a plugin.
 */
public class GateAwareObjectInputStream extends ObjectInputStream {
  /**
   * Creates a GATE aware object input stream to read from the given
   * source.
   */
  public GateAwareObjectInputStream(InputStream source) throws IOException {
    super(source);
  }

  /**
   * Resolve the class of an object read from the stream. First attempts
   * to use the default resolution method provided by ObjectInputStream.
   * If that fails with a ClassNotFoundException then tries to resolve
   * the class via the GATE classloader instead.
   */
  @Override
  protected Class resolveClass(ObjectStreamClass desc) throws IOException,
          ClassNotFoundException {
    try {
      return super.resolveClass(desc);
    }
    catch(ClassNotFoundException cnfe) {
      // try the GATE classloader instead
      return Class.forName(desc.getName(), false, Gate.getClassLoader());
    }
  }

  /**
   * Resolve a proxy class that implements the given interfaces. First
   * attempts to use the default resolution method provided by
   * ObjectInputStream. If that fails with a ClassNotFoundException then
   * tries to resolve the interfaces and create the proxy class using
   * the GATE classloader instead.
   */
  @Override
  protected Class resolveProxyClass(String[] interfaces) throws IOException,
          ClassNotFoundException {
    try {
      return super.resolveProxyClass(interfaces);
    }
    catch(ClassNotFoundException cnfe) {
      // failed to load with the normal method, try the GATE ClassLoader
      // instead
      Class[] interfaceClasses = new Class[interfaces.length];
      for(int i = 0; i < interfaces.length; i++) {
        interfaceClasses[i] = Class.forName(interfaces[i], false, Gate
                .getClassLoader());
      }
      return Proxy.getProxyClass(Gate.getClassLoader(), interfaceClasses);
    }
  }
}