com.scooterframework.web.controller.DefaultContentHandler.java Source code

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Here is the source code for com.scooterframework.web.controller.DefaultContentHandler.java

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/*
 *   This software is distributed under the terms of the FSF
 *   Gnu Lesser General Public License (see lgpl.txt).
 *
 *   This program is distributed WITHOUT ANY WARRANTY. See the
 *   GNU General Public License for more details.
 */
package com.scooterframework.web.controller;

import java.io.IOException;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.json.JSONException;
import org.json.JSONObject;
import org.json.XML;

import com.scooterframework.admin.EnvConfig;
import com.scooterframework.common.logging.LogUtil;
import com.scooterframework.common.util.StringUtil;
import com.scooterframework.orm.activerecord.ActiveRecord;

/**
 * DefaultContentHandler is responsible for handling content of a request
 * format when the specific handler for the format is not available.
 *
 * <p>
 * The content for the following request format is treated as text:
 * json, txt, text, and xml.
 *
 * @author (Fei) John Chen
 */
public class DefaultContentHandler implements ContentHandler {
    private static LogUtil log = LogUtil.getLogger(DefaultContentHandler.class.getName());

    /**
      * Handles result content of a HTTP request.
     *
     * @param request  The HTTP request object.
     * @param response  The HTTP response object.
     * @param content  The content to be sent.
     * @param format  The request format.
     * @throws IOException
     * @throws ServletException
      */
    public void handle(HttpServletRequest request, HttpServletResponse response, Object content, String format)
            throws IOException, ServletException {
        String mimeType = EnvConfig.getInstance().getMimeType(format);

        if (EnvConfig.getInstance().isTextFile(format)) {
            content = convertObjectToString(content, format);
        }

        if ("xml".equalsIgnoreCase(format)) {
            String s = (String) content;
            if (!s.startsWith("<?xml"))
                s = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" + s;
            content = s;
        }

        ContentHandlerHelper.publish(response, content, mimeType);
    }

    protected String convertObjectToString(Object data, String format) {
        String spliter = ", ";
        StringBuilder sb = new StringBuilder();
        if (data instanceof Object[]) {
            for (Object c : (Object[]) data) {
                sb.append(convertObjectToString(c, format)).append(spliter);
            }
        } else if (data instanceof Collection) {
            for (Object c : (Collection<?>) data) {
                sb.append(convertObjectToString(c, format)).append(spliter);
            }
        } else if (data instanceof Iterator) {
            Iterator<?> it = (Iterator<?>) data;
            while (it.hasNext()) {
                sb.append(convertObjectToString(it.next(), format)).append(spliter);
            }
        } else if (data instanceof Map) {
            sb.append(convertMapToString((Map<?, ?>) data, format));
        } else if (data instanceof ActiveRecord) {
            sb.append(convertActiveRecordToString((ActiveRecord) data, format));
        } else {
            sb.append(data);
        }
        return StringUtil.removeLastToken(sb.toString(), spliter);
    }

    protected <K, V> String convertMapToString(Map<K, V> map, String format) {
        StringBuilder sb = new StringBuilder();
        if ("json".equalsIgnoreCase(format)) {
            sb.append((new JSONObject(map)).toString());
        } else if ("xml".equalsIgnoreCase(format)) {
            try {
                sb.append(XML.toString((new JSONObject(map))));
            } catch (JSONException ex) {
                log.error("Failed to conver to xml string: " + ex.getMessage());
            }
        } else {
            sb.append(map.toString());
        }
        return sb.toString();
    }

    protected String convertActiveRecordToString(ActiveRecord record, String format) {
        StringBuilder sb = new StringBuilder();
        if ("json".equalsIgnoreCase(format)) {
            sb.append(record.toJSON());
        } else if ("xml".equalsIgnoreCase(format)) {
            sb.append(record.toXML());
        } else {
            sb.append(record.toString());
        }
        return sb.toString();
    }
}