| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with this |
| * work for additional information regarding copyright ownership. The ASF |
| * licenses this file to You under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| package org.apache.sling.feature.cpconverter.interpolator; |
| |
| import static java.util.Objects.requireNonNull; |
| |
| import java.util.Map; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| public final class SimpleVariablesInterpolator implements VariablesInterpolator { |
| |
| private final Pattern replacementPattern = Pattern.compile("\\$\\{\\{(.+?)\\}\\}"); |
| |
| public String interpolate(String format, Map<String, String> properties) { |
| requireNonNull(format, "Input string format must be not null"); |
| |
| if (properties == null || properties.isEmpty()) { |
| return format; |
| } |
| |
| Matcher matcher = replacementPattern.matcher(format); |
| StringBuffer result = new StringBuffer(); |
| while (matcher.find()) { |
| String variable = matcher.group(1); |
| String resolved = properties.get(variable); |
| |
| if (resolved == null) { |
| resolved = String.format("\\$\\{\\{%s\\}\\}", variable); |
| } |
| |
| matcher.appendReplacement(result, resolved); |
| } |
| matcher.appendTail(result); |
| return result.toString(); |
| } |
| |
| } |