import java.awt.EventQueue;

import org.openide.util.StackElementArray;

    private static boolean asserts = false;

    private static final Set<StackElementArray> stacks;

        assert asserts = true;

        stacks = asserts ? StackElementArray.createSet() : null;

        if (asserts && EventQueue.isDispatchThread() && StackElementArray.addStackIfNew(stacks, 8)) {

            LOG.log(Level.WARNING, "FileUtil.normalizeFile(" + file +") called in EDT", new Exception());

        }

/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

 *

 * Copyright 2013 Oracle and/or its affiliates. All rights reserved.

 *

 * Oracle and Java are registered trademarks of Oracle and/or its affiliates.

 * Other names may be trademarks of their respective owners.

 *

 * The contents of this file are subject to the terms of either the GNU

 * General Public License Version 2 only ("GPL") or the Common

 * Development and Distribution License("CDDL") (collectively, the

 * "License"). You may not use this file except in compliance with the

 * License. You can obtain a copy of the License at

 * http://www.netbeans.org/cddl-gplv2.html

 * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the

 * specific language governing permissions and limitations under the

 * License.  When distributing the software, include this License Header

 * Notice in each file and include the License file at

 * nbbuild/licenses/CDDL-GPL-2-CP.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the GPL Version 2 section of the License file that

 * accompanied this code. If applicable, add the following below the

 * License Header, with the fields enclosed by brackets [] replaced by

 * your own identifying information:

 * "Portions Copyrighted [year] [name of copyright owner]"

 *

 * If you wish your version of this file to be governed by only the CDDL

 * or only the GPL Version 2, indicate your decision by adding

 * "[Contributor] elects to include this software in this distribution

 * under the [CDDL or GPL Version 2] license." If you do not indicate a

 * single choice of license, a recipient has the option to distribute

 * your version of this file under either the CDDL, the GPL Version 2 or

 * to extend the choice of license to its licensees as provided above.

 * However, if you add GPL Version 2 code and therefore, elected the GPL

 * Version 2 license, then the option applies only if the new code is

 * made subject to such option by the copyright holder.

 *

 * Contributor(s):

 *

 * Portions Copyrighted 2013 Sun Microsystems, Inc.

 */

package org.openide.util;

import java.util.Collections;

import java.util.HashSet;

import java.util.Set;

/**

 * Array of stack trace elements may be used for logging of unique stack traces only

 * (for frequent problematic code invocations).

 *

 * @author Miloslav Metelka

 */

public class StackElementArray {

    public static Set<StackElementArray> createSet() {

        return Collections.synchronizedSet(new HashSet<StackElementArray>());

    }

    public static boolean addStackIfNew(Set<StackElementArray> stacks, int stackCompareSize) {

        StackTraceElement[] stackElems = new Exception().getStackTrace();

        int startIndex = 2; // For faster comparison cut of first two (this method and the caller's place)

        int endIndex = Math.min(stackElems.length, startIndex + stackCompareSize);

        StackTraceElement[] compareElems = new StackTraceElement[endIndex - startIndex];

        System.arraycopy(stackElems, startIndex, compareElems, 0, endIndex - startIndex);

        StackElementArray stackElementArray = new StackElementArray(compareElems);

        if (!stacks.contains(stackElementArray)) {

            stacks.add(stackElementArray);

            return true;

        }

        return false;

    }

    private final StackTraceElement[] stackTrace;

    private final int hashCode;

    private StackElementArray(StackTraceElement[] stackTrace) {

        this.stackTrace = stackTrace;

        int hc = 0;

        for (StackTraceElement stackTrace1 : stackTrace) {

            hc ^= stackTrace1.hashCode();

        }

        hashCode = hc;

    }

    int length() {

        return stackTrace.length;

    }

    StackTraceElement element(int i) {

        return stackTrace[i];

    }

    @Override

    public int hashCode() {

        return hashCode;

    }

    @Override

    public boolean equals(Object obj) {

        if (obj == this) {

            return true;

        }

        if (!(obj instanceof StackElementArray)) {

            return false;

        }

        StackElementArray sea = (StackElementArray) obj;

        if (sea.length() != length()) {

            return false;

        }

        for (int i = 0; i < stackTrace.length; i++) {

            if (!element(i).equals(sea.element(i))) {

                return false;

            }

        }

        return true;

    }

}