001/*
002 *    Copyright 2024-2025, Warm-Flow (290631660@qq.com).
003 *
004 *    Licensed under the Apache License, Version 2.0 (the "License");
005 *    you may not use this file except in compliance with the License.
006 *    You may obtain a copy of the License at
007 *
008 *       https://www.apache.org/licenses/LICENSE-2.0
009 *
010 *    Unless required by applicable law or agreed to in writing, software
011 *    distributed under the License is distributed on an "AS IS" BASIS,
012 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *    See the License for the specific language governing permissions and
014 *    limitations under the License.
015 */
016package org.dromara.warm.flow.core.variable;
017
018import org.dromara.warm.flow.core.constant.FlowCons;
019import org.dromara.warm.flow.core.utils.ObjectUtil;
020import org.dromara.warm.flow.core.utils.StringUtils;
021
022import java.util.Map;
023
024/**
025 * 默认变量替换策略： @@default@@|${flag}
026 *
027 * @author warm
028 */
029public class DefaultVariableStrategy implements VariableStrategy {
030
031    @Override
032    public String getType() {
033        return FlowCons.splitAt + "default" + FlowCons.splitAt;
034    }
035
036    @Override
037    public String eval(String expression, Map<String, Object> variable) {
038        String result = expression.replace("${", "").replace("}", "");
039        Object o = variable.get(result);
040        if (ObjectUtil.isNotNull(o)) {
041            String variableStr = (String) o;
042            if (StringUtils.isEmpty(variableStr)) {
043                return null;
044            }
045            return variableStr;
046        }
047        return null;
048    }
049}