pt.webdetails.cda.exporter.JsonExporter.java Source code

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Here is the source code for pt.webdetails.cda.exporter.JsonExporter.java

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/*!
* Copyright 2002 - 2013 Webdetails, a Pentaho company.  All rights reserved.
* 
* This software was developed by Webdetails and is provided under the terms
* of the Mozilla Public License, Version 2.0, or any later version. You may not use
* this file except in compliance with the license. If you need a copy of the license,
* please go to  http://mozilla.org/MPL/2.0/. The Initial Developer is Webdetails.
*
* Software distributed under the Mozilla Public License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or  implied. Please refer to
* the license for the specific language governing your rights and limitations.
*/

package pt.webdetails.cda.exporter;

import java.io.IOException;
import java.io.OutputStream;
import java.util.Map;

import javax.swing.table.TableModel;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import pt.webdetails.cda.utils.MetadataTableModel;

/**
 * JsonExporter
 * <p/>
 * User: pedro Date: Feb 5, 2010 Time: 5:07:12 PM
 */
public class JsonExporter extends AbstractExporter {
    private static final String MIME_TYPE = "application/json";
    private static final Log logger = LogFactory.getLog(XmlExporter.class);
    private String attachmentName;
    boolean isJsonp = false;

    public JsonExporter() {
        super();
    }

    public JsonExporter(Map<String, String> extraSettings) {
        super(extraSettings);
        if (this.getSetting("callback", null) != null) {
            isJsonp = true;
        }
        // the default should be null and if an attachment name is not given as attribute then the file should be
        // returned inline
        this.attachmentName = getSetting(ATTACHMENT_NAME_SETTING, null);

        logger.debug("Initialized JsonExporter with attachement filename '" + attachmentName + "'");
    }

    public void export(final OutputStream out, final TableModel tableModel) throws ExporterException {

        try {
            JSONObject json = getTableAsJson(tableModel, null);

            try {

                if (isJsonp) {
                    out.write(this.getSetting("callback", "xxx").concat("(").getBytes("UTF-8"));
                }

                out.write(json.toString().getBytes("UTF-8"));

                if (isJsonp) {
                    out.write(");".getBytes("UTF-8"));
                }
                out.flush();
            } catch (IOException e) {
                throw new ExporterException("IO Exception converting to utf-8", e);
            }

        } catch (JSONException e) {
            throw new ExporterException("JSONException building object", e);
        }

    }

    public JSONObject getTableAsJson(TableModel tableModel, Integer rowLimit)
            throws JSONException, ExporterException {
        JSONObject json = new JSONObject();

        // Generate metadata
        final JSONArray metadataArray = new JSONArray();

        final int columnCount = tableModel.getColumnCount();
        int rowCount = tableModel.getRowCount();

        if (rowLimit != null) {
            rowCount = Math.min(rowCount, rowLimit);
        }

        boolean[] isColumnDouble = new boolean[columnCount];
        for (int i = 0; i < columnCount; i++) {
            JSONObject info = new JSONObject();
            info.put("colIndex", i);
            info.put("colName", tableModel.getColumnName(i));
            Class<?> columnClass = tableModel.getColumnClass(i);
            isColumnDouble[i] = (columnClass.isAssignableFrom(Double.class));
            info.put("colType", getColType(columnClass));
            metadataArray.put(info);
        }
        json.put("metadata", metadataArray);

        if (tableModel instanceof MetadataTableModel) {
            json.put("queryInfo", ((MetadataTableModel) tableModel).getAllMetadata());
        }
        final JSONArray valuesArray = new JSONArray();

        for (int rowIdx = 0; rowIdx < rowCount; rowIdx++) {
            final JSONArray rowArray = new JSONArray();
            for (int colIdx = 0; colIdx < columnCount; colIdx++) {
                Object value = tableModel.getValueAt(rowIdx, colIdx);
                try {
                    if (value != null && isColumnDouble[colIdx] && ((Double) value).isInfinite()) {
                        value = null;
                        //value = Double.POSITIVE_INFINITY == (Double) value ? "Infinity" : "-Infinity";//workaround for JSON
                        // issue with Infinity
                    }
                } catch (ClassCastException e) {
                } //just because it says Double doesn't mean we don't get oranges
                rowArray.put(value);
            }
            valuesArray.put(rowArray);
        }
        json.put("resultset", valuesArray);
        return json;
    }

    public String getMimeType() {
        return MIME_TYPE;
    }

    public String getAttachmentName() {
        return attachmentName;
    }
}