com.example.journal.env.JournalEnvironmentPostProcessor.java Source code

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Here is the source code for com.example.journal.env.JournalEnvironmentPostProcessor.java

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/*
 * Copyright 2012-2015 the original author or authors.
 *
 * Licensed 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 com.example.journal.env;

import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Properties;

import org.springframework.beans.factory.config.YamlPropertiesFactoryBean;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.env.EnvironmentPostProcessor;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.MapPropertySource;
import org.springframework.core.env.MutablePropertySources;
import org.springframework.core.env.PropertySource;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;

import com.example.journal.JournalEntry;
import com.example.journal.ledger.JournalSink;

/**
 * @author Dave Syer
 *
 */
public class JournalEnvironmentPostProcessor implements EnvironmentPostProcessor {

    private static final String PROPERTY_SOURCE_NAME = "defaultProperties";

    @Override
    public void postProcessEnvironment(ConfigurableEnvironment environment, SpringApplication application) {
        Map<String, Object> map = new LinkedHashMap<>();
        contributeDefaults(map, new ClassPathResource("journal.yml"));
        map.put("spring.cloud.stream.bindings." + JournalSink.INPUT + ".content-type",
                "application/x-java-object;type=" + JournalEntry.class.getName());
        addOrReplace(environment.getPropertySources(), map);
    }

    private void addOrReplace(MutablePropertySources propertySources, Map<String, Object> map) {
        MapPropertySource target = null;
        if (propertySources.contains(PROPERTY_SOURCE_NAME)) {
            PropertySource<?> source = propertySources.get(PROPERTY_SOURCE_NAME);
            if (source instanceof MapPropertySource) {
                target = (MapPropertySource) source;
                for (String key : map.keySet()) {
                    if (!target.containsProperty(key)) {
                        target.getSource().put(key, map.get(key));
                    }
                }
            }
        }
        if (target == null) {
            target = new MapPropertySource(PROPERTY_SOURCE_NAME, map);
        }
        if (!propertySources.contains(PROPERTY_SOURCE_NAME)) {
            propertySources.addLast(target);
        }
    }

    private void contributeDefaults(Map<String, Object> defaults, Resource resource) {
        if (resource.exists()) {
            YamlPropertiesFactoryBean yamlPropertiesFactoryBean = new YamlPropertiesFactoryBean();
            yamlPropertiesFactoryBean.setResources(resource);
            yamlPropertiesFactoryBean.afterPropertiesSet();
            Properties p = yamlPropertiesFactoryBean.getObject();
            for (Object k : p.keySet()) {
                String key = k.toString();
                defaults.put(key, p.get(key));
            }
        }
    }

}