org.openmrs.obs.handler.ImageHandler.java Source code

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Here is the source code for org.openmrs.obs.handler.ImageHandler.java

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/**
 * This Source Code Form is subject to the terms of the Mozilla Public License,
 * v. 2.0. If a copy of the MPL was not distributed with this file, You can
 * obtain one at http://mozilla.org/MPL/2.0/. OpenMRS is also distributed under
 * the terms of the Healthcare Disclaimer located at http://openmrs.org/license.
 *
 * Copyright (C) OpenMRS Inc. OpenMRS is a registered trademark and the OpenMRS
 * graphic logo is a trademark of OpenMRS Inc.
 */
package org.openmrs.obs.handler;

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashSet;
import java.util.Set;
import java.util.Iterator;

import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.stream.FileImageInputStream;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.openmrs.Obs;
import org.openmrs.api.APIException;
import org.openmrs.obs.ComplexData;
import org.openmrs.obs.ComplexObsHandler;

/**
 * Handler for storing basic images for complex obs to the file system. The image mime type used is
 * taken from the image name. if the .* image name suffix matches
 * {@link javax.imageio.ImageIO#getWriterFormatNames()} then that mime type will be used to save the
 * image. Images are stored in the location specified by the global property: "obs.complex_obs_dir"
 * 
 * @see org.openmrs.util.OpenmrsConstants#GLOBAL_PROPERTY_COMPLEX_OBS_DIR
 * @since 1.5
 */
public class ImageHandler extends AbstractHandler implements ComplexObsHandler {

    /** Views supported by this handler */
    private static final String[] supportedViews = { ComplexObsHandler.RAW_VIEW };

    public static final Log log = LogFactory.getLog(ImageHandler.class);

    private Set<String> extensions;

    /**
     * Constructor initializes formats for alternative file names to protect from unintentionally
     * overwriting existing files.
     */
    public ImageHandler() {
        super();

        // Create a HashSet to quickly check for supported extensions.
        extensions = new HashSet<String>();
        for (String mt : ImageIO.getWriterFormatNames()) {
            extensions.add(mt);
        }
    }

    /**
     * Currently supports all views and puts the Image file data into the ComplexData object
     * 
     * @see org.openmrs.obs.ComplexObsHandler#getObs(org.openmrs.Obs, java.lang.String)
     */
    public Obs getObs(Obs obs, String view) {
        File file = getComplexDataFile(obs);

        // Raw image
        if (ComplexObsHandler.RAW_VIEW.equals(view)) {
            BufferedImage img = null;
            try {
                img = ImageIO.read(file);
            } catch (IOException e) {
                log.error("Trying to read file: " + file.getAbsolutePath(), e);
            }

            ComplexData complexData = new ComplexData(file.getName(), img);

            // Image MIME type
            try {
                FileImageInputStream imgStream = new FileImageInputStream(file);
                Iterator<ImageReader> imgReader = ImageIO.getImageReaders(imgStream);
                imgStream.close();
                if (imgReader.hasNext()) {
                    complexData.setMimeType("image/" + imgReader.next().getFormatName().toLowerCase());
                } else {
                    log.warn("MIME type of " + file.getAbsolutePath() + " is not known");
                }
            } catch (FileNotFoundException e) {
                log.error("Image " + file.getAbsolutePath() + " was not found", e);
            } catch (IOException e) {
                log.error("Trying to determine MIME type of " + file.getAbsolutePath(), e);
            }

            obs.setComplexData(complexData);
        } else {
            // No other view supported
            // NOTE: if adding support for another view, don't forget to update supportedViews list above
            return null;
        }

        return obs;
    }

    /**
     * @see org.openmrs.obs.ComplexObsHandler#getSupportedViews()
     */
    @Override
    public String[] getSupportedViews() {
        return supportedViews;
    }

    /**
     * @see org.openmrs.obs.ComplexObsHandler#saveObs(org.openmrs.Obs)
     */
    public Obs saveObs(Obs obs) throws APIException {
        // Get the buffered image from the ComplexData.
        BufferedImage img = null;

        Object data = obs.getComplexData().getData();
        if (data instanceof BufferedImage) {
            img = (BufferedImage) obs.getComplexData().getData();
        } else if (data instanceof InputStream) {
            try {
                img = ImageIO.read((InputStream) data);
                if (img == null) {
                    throw new IllegalArgumentException("Invalid image file");
                }
            } catch (IOException e) {
                throw new APIException("Obs.error.unable.convert.complex.data", new Object[] { "input stream" }, e);
            }
        }

        if (img == null) {
            throw new APIException("Obs.error.cannot.save.complex", new Object[] { obs.getObsId() });
        }

        try {
            File outfile = getOutputFileToWrite(obs);

            String extension = getExtension(obs.getComplexData().getTitle());

            // TODO: Check this extension against the registered extensions for validity

            // Write the file to the file system.
            ImageIO.write(img, extension, outfile);

            // Set the Title and URI for the valueComplex
            obs.setValueComplex(extension + " image |" + outfile.getName());

            // Remove the ComlexData from the Obs
            obs.setComplexData(null);

        } catch (IOException ioe) {
            throw new APIException("Obs.error.trying.write.complex", null, ioe);
        }

        return obs;
    }

}