com.qdeve.oilprice.reader.ContentReader.java Source code

Introduction

Here is the source code for com.qdeve.oilprice.reader.ContentReader.java

Source

/**************************************************************************
 * (C) Copyright 2016 QDEVE Roman Krysinski.
 *
 * 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.qdeve.oilprice.reader;

import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;

import org.apache.commons.io.IOUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.core.io.Resource;
import org.springframework.stereotype.Component;
import org.springframework.web.client.RestClientException;
import org.springframework.web.client.RestTemplate;

import com.qdeve.oilprice.ProcessingException;
import com.qdeve.oilprice.configuration.OilPriceProperties;

/**
 * Gets the content of resource defined in
 * {@link OilPriceProperties#getContentPath()}, which can points to e.g.
 * file://file/html or http://somesite/somefile.html
 *
 * @author Roman Krysinski
 */
@Component
class ContentReader {
    private static final String DEFAULT_ENCODING = "UTF-8";

    @Autowired
    private OilPriceProperties properties;
    @Autowired
    private ApplicationContext applCtx;
    @Autowired
    private RestTemplate restTemplate;

    public String get() {
        String body = null;
        if (properties.getContentPath().startsWith("http")) {
            body = getContentViaHttpClient();
        } else {
            body = getContentFromFile();
        }
        return body;
    }

    private String getContentFromFile() {
        String body = null;
        Resource resource = applCtx.getResource(properties.getContentPath());
        InputStream inputStream;
        try {
            inputStream = resource.getInputStream();
            StringWriter writer = new StringWriter();
            IOUtils.copy(inputStream, writer, DEFAULT_ENCODING);
            body = writer.toString();
        } catch (IOException e) {
            throw new ProcessingException("Failed to retrieve content from " + properties.getContentPath()
                    + ", reason: " + e.getMessage(), e);
        }
        return body;
    }

    private String getContentViaHttpClient() {
        String body = null;
        try {
            body = restTemplate.getForObject(properties.getContentPath(), String.class);
        } catch (RestClientException e) {
            throw new ProcessingException("Failed to retrieve content from " + properties.getContentPath()
                    + ", reason: " + e.getMessage(), e);
        }

        return body;
    }
}