ClassLoaderReference.java

/*
 * Copyright 1998-2004 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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package com.sun.jdi;

import java.util.List;

/**
 * A class loader object from the target VM.
 * A ClassLoaderReference is an {@link ObjectReference} with additional
 * access to classloader-specific information from the target VM. Instances
 * ClassLoaderReference are obtained through calls to
 * {@link ReferenceType#classLoader}
 *
 * @see ObjectReference
 *
 * @author Gordon Hirsch
 * @since  1.3
 */
public interface ClassLoaderReference extends ObjectReference {

    /**
     * Returns a list of all loaded classes that were defined by this
     * class loader. No ordering of this list guaranteed.
     * <P>
     * The returned list will include reference types
     * loaded at least to the point of preparation and
     * types (like array) for which preparation is
     * not defined.
     *
     * @return a List of {@link ReferenceType} objects mirroring types
     * loaded by this class loader. The list has length 0 if no types
     * have been defined by this classloader.
     */
    List<ReferenceType> definedClasses();

    /**
     * Returns a list of all classes for which this class loader has
     * been recorded as the initiating loader in the target VM.
     * The list contains ReferenceTypes defined directly by this loader
     * (as returned by {@link #definedClasses}) and any types for which
     * loading was delegated by this class loader to another class loader.
     * <p>
     * The visible class list has useful properties with respect to
     * the type namespace. A particular type name will occur at most
     * once in the list. Each field or variable declared with that
     * type name in a class defined by
     * this class loader must be resolved to that single type.
     * <p>
     * No ordering of the returned list is guaranteed.
     * <p>
     * See the revised
     * <a href="http://java.sun.com/docs/books/vmspec/">Java
     * Virtual Machine Specification</a> section
     * <a href="http://java.sun.com/docs/books/vmspec/2nd-edition/html/ConstantPool.doc.html#72007">5.3
     * Creation and Loading</a>
     * for more information on the initiating classloader.
     * <p>
     * Note that unlike {@link #definedClasses()}
     * and {@link VirtualMachine#allClasses()},
     * some of the returned reference types may not be prepared.
     * Attempts to perform some operations on unprepared reference types
     * (e.g. {@link ReferenceType#fields() fields()}) will throw
     * a {@link ClassNotPreparedException}.
     * Use {@link ReferenceType#isPrepared()} to determine if
     * a reference type is prepared.
     *
     * @return a List of {@link ReferenceType} objects mirroring classes
     * initiated by this class loader. The list has length 0 if no classes
     * are visible to this classloader.
     */
    List<ReferenceType> visibleClasses();
}