/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

package com.sun.org.apache.bcel.internal;

/* ====================================================================

 * The Apache Software License, Version 1.1

 *

 * Copyright (c) 2001 The Apache Software Foundation.  All rights

 * reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 *

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 *

 * 3. The end-user documentation included with the redistribution,

 *    if any, must include the following acknowledgment:

 *       "This product includes software developed by the

 *        Apache Software Foundation (http://www.apache.org/)."

 *    Alternately, this acknowledgment may appear in the software itself,

 *    if and wherever such third-party acknowledgments normally appear.

 *

 * 4. The names "Apache" and "Apache Software Foundation" and

 *    "Apache BCEL" must not be used to endorse or promote products

 *    derived from this software without prior written permission. For

 *    written permission, please contact apache@apache.org.

 *

 * 5. Products derived from this software may not be called "Apache",

 *    "Apache BCEL", nor may "Apache" appear in their name, without

 *    prior written permission of the Apache Software Foundation.

 *

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED

 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES

 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR

 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT

 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 * ====================================================================

 *

 * This software consists of voluntary contributions made by many

 * individuals on behalf of the Apache Software Foundation.  For more

 * information on the Apache Software Foundation, please see

 * <http://www.apache.org/>.

 */

import com.sun.org.apache.bcel.internal.classfile.JavaClass;

import com.sun.org.apache.bcel.internal.util.*;

import java.io.*;

/**

 * The repository maintains informations about class interdependencies, e.g.,

 * whether a class is a sub-class of another. Delegates actual class loading

 * to SyntheticRepository with current class path by default.

 *

 * @see com.sun.org.apache.bcel.internal.util.Repository

 * @see com.sun.org.apache.bcel.internal.util.SyntheticRepository

 *

 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>

 */

public abstract class Repository {

  private static com.sun.org.apache.bcel.internal.util.Repository _repository =

    SyntheticRepository.getInstance();

  /** @return currently used repository instance

   */

  public static com.sun.org.apache.bcel.internal.util.Repository getRepository() {

    return _repository;

  }

  /** Set repository instance to be used for class loading

   */

  public static void setRepository(com.sun.org.apache.bcel.internal.util.Repository rep) {

    _repository = rep;

  }

  /** Lookup class somewhere found on your CLASSPATH, or whereever the

   * repository instance looks for it.

   *

   * @return class object for given fully qualified class name, or null

   * if the class could not be found or parsed correctly

   */

  public static JavaClass lookupClass(String class_name) {

    try {

      JavaClass clazz = _repository.findClass(class_name);

      if(clazz == null) {

        return _repository.loadClass(class_name);

      } else {

        return clazz;

      }

    } catch(ClassNotFoundException ex) { return null; }

  }

  /**

   * Try to find class source via getResourceAsStream().

   * @see Class

   * @return JavaClass object for given runtime class

   */

  public static JavaClass lookupClass(Class clazz) {

    try {

      return _repository.loadClass(clazz);

    } catch(ClassNotFoundException ex) { return null; }

  }

  /** @return class file object for given Java class.

   */

  public static ClassPath.ClassFile lookupClassFile(String class_name) {

    try {

      return ClassPath.SYSTEM_CLASS_PATH.getClassFile(class_name);

    } catch(IOException e) { return null; }

  }

  /** Clear the repository.

   */

  public static void clearCache() {

    _repository.clear();

  }

  /**

   * Add clazz to repository if there isn't an equally named class already in there.

   *

   * @return old entry in repository

   */

  public static JavaClass addClass(JavaClass clazz) {

    JavaClass old = _repository.findClass(clazz.getClassName());

    _repository.storeClass(clazz);

    return old;

  }

  /**

   * Remove class with given (fully qualified) name from repository.

   */

  public static void removeClass(String clazz) {

    _repository.removeClass(_repository.findClass(clazz));

  }

  /**

   * Remove given class from repository.

   */

  public static void removeClass(JavaClass clazz) {

    _repository.removeClass(clazz);

  }

  /**

   * @return list of super classes of clazz in ascending order, i.e.,

   * Object is always the last element

   */

  public static JavaClass[] getSuperClasses(JavaClass clazz) {

    return clazz.getSuperClasses();

  }

  /**

   * @return list of super classes of clazz in ascending order, i.e.,

   * Object is always the last element. return "null", if class

   * cannot be found.

   */

  public static JavaClass[] getSuperClasses(String class_name) {

    JavaClass jc = lookupClass(class_name);

    return (jc == null? null : getSuperClasses(jc));

  }

  /**

   * @return all interfaces implemented by class and its super

   * classes and the interfaces that those interfaces extend, and so on.

   * (Some people call this a transitive hull).

   */

  public static JavaClass[] getInterfaces(JavaClass clazz) {

    return clazz.getAllInterfaces();

  }

  /**

   * @return all interfaces implemented by class and its super

   * classes and the interfaces that extend those interfaces, and so on

   */

  public static JavaClass[] getInterfaces(String class_name) {

    return getInterfaces(lookupClass(class_name));

  }

  /**

   * Equivalent to runtime "instanceof" operator.

   * @return true, if clazz is an instance of super_class

   */

  public static boolean instanceOf(JavaClass clazz, JavaClass super_class) {

    return clazz.instanceOf(super_class);

  }

  /**

   * @return true, if clazz is an instance of super_class

   */

  public static boolean instanceOf(String clazz, String super_class) {

    return instanceOf(lookupClass(clazz), lookupClass(super_class));

  }

  /**

   * @return true, if clazz is an instance of super_class

   */

  public static boolean instanceOf(JavaClass clazz, String super_class) {

    return instanceOf(clazz, lookupClass(super_class));

  }

  /**

   * @return true, if clazz is an instance of super_class

   */

  public static boolean instanceOf(String clazz, JavaClass super_class) {

    return instanceOf(lookupClass(clazz), super_class);

  }

  /**

   * @return true, if clazz is an implementation of interface inter

   */

  public static boolean implementationOf(JavaClass clazz, JavaClass inter) {

    return clazz.implementationOf(inter);

  }

  /**

   * @return true, if clazz is an implementation of interface inter

   */

  public static boolean implementationOf(String clazz, String inter) {

    return implementationOf(lookupClass(clazz), lookupClass(inter));

  }

  /**

   * @return true, if clazz is an implementation of interface inter

   */

  public static boolean implementationOf(JavaClass clazz, String inter) {

    return implementationOf(clazz, lookupClass(inter));

  }

  /**

   * @return true, if clazz is an implementation of interface inter

   */

  public static boolean implementationOf(String clazz, JavaClass inter) {

    return implementationOf(lookupClass(clazz), inter);

  }

}