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/*
 * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package com.sun.el.parser;

import java.util.Collection;
import java.util.Map;

import jakarta.el.ELException;

import com.sun.el.lang.EvaluationContext;

/**
 * @author Jacob Hookom [[email protected]]
 * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: kchung $
 */
public final class AstEmpty extends SimpleNode {
    public AstEmpty(int id) {
        super(id);
    }

    @Override
    public Class getType(EvaluationContext ctx) throws ELException {
        return Boolean.class;
    }

    @Override
    public Object getValue(EvaluationContext ctx) throws ELException {
        Object obj = this.children[0].getValue(ctx);
        if (obj == null) {
            return Boolean.TRUE;
        } else if (obj instanceof String) {
            return Boolean.valueOf(((String) obj).length() == 0);
        } else if (obj instanceof Object[]) {
            return Boolean.valueOf(((Object[]) obj).length == 0);
        } else if (obj instanceof Collection) {
            return Boolean.valueOf(((Collection) obj).isEmpty());
        } else if (obj instanceof Map) {
            return Boolean.valueOf(((Map) obj).isEmpty());
        }
        return Boolean.FALSE;
    }
}