inti.ws.spring.resource.config.ConfigParserProvider.java Source code

Introduction

Here is the source code for inti.ws.spring.resource.config.ConfigParserProvider.java

Source

/**
 * Copyright 2012 the project-owners
 *
 *    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 inti.ws.spring.resource.config;

import inti.ws.spring.resource.WebResource;

import java.io.InputStream;
import java.net.URL;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

import javax.inject.Inject;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Component;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

@Component
public class ConfigParserProvider {

    private static final Logger LOGGER = LoggerFactory.getLogger(ConfigParserProvider.class);

    protected ObjectMapper mapper = new ObjectMapper();
    @Inject
    ApplicationContext context;

    public Map<String, ConfigParser<? extends WebResource>> getConfigParsers(ClassLoader classLoader)
            throws Exception {
        Enumeration<URL> parserLocations = classLoader.getResources("META-INF/inti.ws.spring.resource/parser.json");
        URL url;
        ConfigParserSettings settings = null;
        InputStream inputStream;
        JsonNode node;
        Entry<String, JsonNode> field;
        Iterator<Entry<String, JsonNode>> fields;
        Map<String, ConfigParser<? extends WebResource>> parsers = new HashMap<>();
        ConfigParser<? extends WebResource> parser;

        while (parserLocations.hasMoreElements()) {
            url = parserLocations.nextElement();
            LOGGER.debug("getConfigParsers - scanning url={}", url);
            inputStream = url.openStream();
            try {
                node = mapper.readTree(inputStream);
                fields = node.fields();
                while (fields.hasNext()) {
                    field = fields.next();
                    settings = mapper.convertValue(field.getValue(), ConfigParserSettings.class);
                    parser = context.getBean(settings.getConfigurator());
                    parser.setConfigParserSettings(settings);
                    if (parsers.containsKey(field.getKey())) {
                        throw new RuntimeException(
                                "name collision detected: '" + field.getKey() + "' already engaged.");
                    }
                    LOGGER.debug("getConfigParsers - found parser for key={}: {}", field.getKey(), parser);
                    parsers.put(field.getKey(), parser);
                }
            } finally {
                inputStream.close();
            }
        }

        return parsers;
    }

}