OpenBISScreeningML.java

/*
 * Copyright 2010 ETH Zuerich, CISD
 *
 * 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.
 */

import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import ch.systemsx.cisd.openbis.dss.client.api.v1.IDataSetDss;
import ch.systemsx.cisd.openbis.dss.generic.shared.api.v1.NewDataSetMetadataDTO;
import ch.systemsx.cisd.openbis.generic.client.cli.Login;
import ch.systemsx.cisd.openbis.plugin.screening.client.api.v1.IScreeningOpenbisServiceFacade;
import ch.systemsx.cisd.openbis.plugin.screening.client.api.v1.ScreeningOpenbisServiceFacade.IImageOutputStreamProvider;
import ch.systemsx.cisd.openbis.plugin.screening.client.api.v1.ScreeningOpenbisServiceFacadeFactory;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.ExperimentIdentifier;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.FeatureVector;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.FeatureVectorDataset;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.FeatureVectorDatasetReference;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.FeatureVectorWithDescription;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.ImageDatasetMetadata;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.ImageDatasetReference;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.MaterialIdentifier;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.MaterialTypeIdentifier;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.Plate;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.PlateIdentifier;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.PlateImageReference;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.PlateWellMaterialMapping;
import ch.systemsx.cisd.openbis.plugin.screening.shared.api.v1.dto.WellPosition;

/**
 * Simple Matlab interface for openBIS for Screening. It is meant to be used in one Matlab session
 * at a time, i.e. it is <i>not</i> multi-threading safe.
 * <p>
 * While written in Java, the API is idiomatic for Matlab, i.e. values are returned as
 * multi-dimensional arrays. For the <code>get...</code> and <code>load...</code> methods the first
 * index will contain the actual data, while the second index will contain per-row annotations. For
 * <code>getFeatureMatrix</code>, the third index contains per-column annotations. This allows
 * simple access with Matlab's slicing operator, see doc of e.g. {@link #getFeatureMatrix(String)}.
 * <p>
 * A typical Matlab session looks like:
 * 
 * <pre>
 * % Add the API jar file to the classpath
 * javaaddpath('/home/brinn/matlab/openbis_screening_api-batteries_included.jar')
 * % Login to server
 * OpenBISScreeningML.login('user', 'secret', 'https://www.infectome.org')
 * 
 * % ...perform calls on the server...
 * 
 * % Logout to close the session on the server
 * OpenBISScreeningML.logout()
 * </pre>
 * 
 * <i>Note: using this login your password will end up in the Matlab command history. An alternative
 * that avoids this is to call the
 * {@link ch.systemsx.cisd.openbis.generic.client.cli.Login} class. Logging in on the
 * console will grant this class access to the openBIS server.</i>
 * 
 * @author Bernd Rinn
 */
public class OpenBISScreeningML
{
    private static interface ITileNumberIterable extends Iterable<Integer>
    {
        public void setMaximumNumberOfTiles(int numberOfTiles);
        public int getMaximumNumberOfTiles();
    }
    
    private static final class ImageReferenceAndFile
    {
        private final PlateImageReference imageReference;
        private final File imageFile;
        private BufferedOutputStream outputStream;

        ImageReferenceAndFile(PlateImageReference imageReference, File imageFile)
        {
            this.imageReference = imageReference;
            this.imageFile = imageFile;
        }

        public PlateImageReference getImageReference()
        {
            return imageReference;
        }

        public File getImageFile()
        {
            return imageFile;
        }
        
        public OutputStream open() throws IOException
        {
            if (outputStream == null)
            {
                outputStream = new BufferedOutputStream(new FileOutputStream(imageFile));
            }
            return outputStream;
        }
        
        public void close() throws IOException
        {
            if (outputStream != null)
            {
                outputStream.close();
            }
            outputStream = null;
        }
    }
    
    private static File temporarySessionDir;
    
    private static Map<PlateImageReference, File> loadedImages;

    private static IScreeningOpenbisServiceFacade openbis = null;

    private static List<ExperimentIdentifier> experiments = null;

    private static List<Plate> plates = null;

    private static Map<String, List<Plate>> experimentToPlateMap =
            new HashMap<String, List<Plate>>();

    private static Map<String, ExperimentIdentifier> experimentCodeToExperimentMap =
            new HashMap<String, ExperimentIdentifier>();

    private static Map<String, Plate> plateCodeToPlateMap = new HashMap<String, Plate>();

    private OpenBISScreeningML()
    {
        // Not to be constructed.
    }

    //
    // Versioning
    //

    /**
     * The version of the API.
     */
    public static final String VERSION = "1";

    /**
     * The required version ("major.minor") of the screening API on the openBIS application server.
     */
    public static final String REQUIRES_OPENBIS_AS_API = "1.7";

    /**
     * The required version ("major.minor") of the screening API on the openBIS datastore server.
     */
    public static final String REQUIRES_OPENBIS_DSS_API = "1.1";

    private static File dataSetsDir;

    //
    // Authentication methods
    //

    /**
     * Login to the openBIS server given as <var>url</var>.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * OpenBISScreeningML.login('user', 'secret', 'https://www.infectome.org')
     * </pre>
     * 
     * @param user The user id on the server
     * @param password The password on the server
     * @param url The URL, e.g. <code>https://www.infectome.org</var>
     */
    public static void login(String user, String password, String url)
    {
        openbis = ScreeningOpenbisServiceFacadeFactory.tryCreate(user, password, url);
        if (openbis == null)
        {
            throw new RuntimeException("Login failed.");
        }
        init();
    }

    private static void init()
    {
        File tempDir = new File(System.getProperty("java.io.tmpdir"));
        dataSetsDir = new File(tempDir, "openbis_datasets");
        if (dataSetsDir.isDirectory() == false && dataSetsDir.mkdirs() == false)
        {
            throw new RuntimeException("Couldn't create a data set directory.");
        }
        temporarySessionDir = new File(tempDir, "openbis_" + System.currentTimeMillis() / 1000 + "_temp_dir");
        if (temporarySessionDir.mkdirs() == false)
        {
            throw new RuntimeException("Couldn't create a temporary directory.");
        }
        loadedImages = new HashMap<PlateImageReference, File>();
        experiments = openbis.listExperiments();
        experimentCodeToExperimentMap.clear();
        for (ExperimentIdentifier e : experiments)
        {
            experimentCodeToExperimentMap.put(e.getAugmentedCode(), e);
        }
        plates = openbis.listPlates();
        plateCodeToPlateMap.clear();
        experimentToPlateMap.clear();
        for (Plate p : plates)
        {
            final String plateCode = p.getAugmentedCode();
            plateCodeToPlateMap.put(plateCode, p);
            final String experimentCode = p.getExperimentIdentifier().getAugmentedCode();
            List<Plate> experimentPlates = experimentToPlateMap.get(experimentCode);
            if (experimentPlates == null)
            {
                experimentPlates = new ArrayList<Plate>();
                experimentToPlateMap.put(experimentCode, experimentPlates);
            }
            experimentPlates.add(p);
        }
    }

    /**
     * Logs out and closes the session on the server.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * OpenBISScreeningML.logout()
     * </pre>
     */
    public static void logout()
    {
        if (openbis == null)
        {
            return;
        }
        openbis.logout();
        if (Login.OPENBIS_TOKEN_FILE.exists())
        {
            Login.OPENBIS_TOKEN_FILE.delete();
        }
        openbis = null;
    }

    //
    // Information methods
    //

    /**
     * Lists all experiment.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Get the experiments
     * exps = OpenBISScreeningML.listExperiments();
     * % How many experiments do we have?
     * length(exps)
     * % Get all information about experiment 3
     * exp3 = exps(3,:)
     * % Get the perm ids for all experiments
     * permids = exps(:,2)
     * </pre>
     * 
     * @return Each row contains information about one plate:
     *         <p>
     *         <code>{ experiment augmented code, experiment perm id, experiment space code, 
     *         experiment project code, experiment code }</code>
     */
    public static Object[][] listExperiments()
    {
        checkLoggedIn();
        final Object[][] result = new Object[experiments.size()][5];
        for (int i = 0; i < experiments.size(); ++i)
        {
            final Object[] annotations =
                    new Object[]
                        { experiments.get(i).getAugmentedCode(), experiments.get(i).getPermId(),
                                experiments.get(i).getSpaceCode(),
                                experiments.get(i).getProjectCode(),
                                experiments.get(i).getExperimentCode() };
            System.arraycopy(annotations, 0, result[i], 0, annotations.length);
        }
        return result;
    }

    /**
     * Lists all plates.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Get the plates
     * plates = OpenBISScreeningML.listPlates();
     * % How many plates do we have?
     * length(plates)
     * % Get all information about plate 2
     * plate2 = plates(2,:)
     * % Get the simple plate codes for all plates
     * codes = plates(:,4)
     * </pre>
     * 
     * @return Each row contains information about one plate:
     *         <p>
     *         <code>{ plate augmented code, plate perm id, plate space code, plate code, 
     *         experiment augmented code, experiment perm id, experiment space code, 
     *         experiment project code, experiment code }</code>
     */
    public static Object[][] listPlates()
    {
        checkLoggedIn();
        final Object[][] result = new Object[plates.size()][9];
        for (int i = 0; i < plates.size(); ++i)
        {
            final Object[] annotations =
                    new Object[]
                        { plates.get(i).getAugmentedCode(), plates.get(i).getPermId(),
                                plates.get(i).tryGetSpaceCode(), plates.get(i).getPlateCode(),
                                plates.get(i).getExperimentIdentifier().getAugmentedCode(),
                                plates.get(i).getExperimentIdentifier().getPermId(),
                                plates.get(i).getExperimentIdentifier().getSpaceCode(),
                                plates.get(i).getExperimentIdentifier().getProjectCode(),
                                plates.get(i).getExperimentIdentifier().getExperimentCode(), };
            System.arraycopy(annotations, 0, result[i], 0, annotations.length);
        }
        return result;
    }
    
    /**
     * Lists the plates of <var>experiment</var>.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Get the plates of experiment MYEXP in project PROJ of space SPACE
     * plates = OpenBISScreeningML.listPlates('/SPACE/PROJ/MYEXP');
     * % How many plates do we have?
     * length(plates)
     * % Get all information about plate 2
     * plate2 = plates(2,:)
     * % Get the augmented plate codes for all plates
     * acodes = plates(:,1)
     * </pre>
     * 
     * @param experiment The augmented code of the experiment to list the plates for
     * @return Each row contains information about one plate:
     *         <p>
     *         <code>{ plate augmented code, plate perm id, plate space code, plate code, 
     *         experiment augmented code, experiment perm id, experiment space code, 
     *         experiment project code, experiment code }</code>
     */
    public static Object[][] listPlates(String experiment)
    {
        checkLoggedIn();
        final List<Plate> experimentPlates = experimentToPlateMap.get(experiment);
        if (experimentPlates == null)
        {
            throw new RuntimeException("No experiment with that code found.");
        }
        final Object[][] result = new Object[experimentPlates.size()][9];
        for (int i = 0; i < experimentPlates.size(); ++i)
        {
            final Object[] annotations =
                    new Object[]
                        {
                                experimentPlates.get(i).getAugmentedCode(),
                                plates.get(i).getPermId(),
                                experimentPlates.get(i).tryGetSpaceCode(),
                                plates.get(i).getPlateCode(),
                                experimentPlates.get(i).getExperimentIdentifier()
                                        .getAugmentedCode(),
                                experimentPlates.get(i).getExperimentIdentifier().getPermId(),
                                experimentPlates.get(i).getExperimentIdentifier().getSpaceCode(),
                                experimentPlates.get(i).getExperimentIdentifier().getProjectCode(),
                                experimentPlates.get(i).getExperimentIdentifier()
                                        .getExperimentCode(), };
            System.arraycopy(annotations, 0, result[i], 0, annotations.length);
        }
        return result;
    }

    /**
     * Lists all channels measured in <var>experiment</var>.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Get the channels of experiment MYEXP in project PROJ of space SPACE
     * channels = OpenBISScreeningML.listChannels('/SPACE/PROJ/MYEXP');
     * % How many channels do we have?
     * length(channels)
     * % What is the name of channel 1?
     * channels(1)
     * </pre>
     * 
     * @param experiment The augmented code of the experiment to list the channels for
     * @return Each row contains information about one channel. Currently the only information
     *         available is the channel name.
     */
    public static Object[][] listChannels(String experiment)
    {
        checkLoggedIn();
        final List<Plate> experimentPlates = experimentToPlateMap.get(experiment);
        if (experimentPlates == null)
        {
            throw new RuntimeException("No experiment with that code found.");
        }
        if (experimentPlates.isEmpty())
        {
            return new Object[0][];
        }
        final List<ImageDatasetReference> imageDatasets =
                openbis.listRawImageDatasets(experimentPlates);
        if (imageDatasets.isEmpty())
        {
            return new Object[0][];
        }
        final List<ImageDatasetMetadata> meta =
                openbis.listImageMetadata(Arrays.asList(imageDatasets.get(0)));
        if (meta.isEmpty())
        {
            return new Object[0][];
        }
        final List<String> channels = getChannelCodes(meta);
        Object[][] result = new Object[channels.size()][1];
        for (int i = 0; i < result.length; ++i)
        {
            result[i][0] = channels.get(i);
        }
        return result;
    }

    @SuppressWarnings("deprecation")
    private static List<String> getChannelCodes(final List<ImageDatasetMetadata> meta)
    {
        return meta.get(0).getChannelNames();
    }

    /**
     * Lists all features computed for <var>experiment</var>.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Get the features of experiment MYEXP in project PROJ of space SPACE
     * features = OpenBISScreeningML.listFeatures('/SPACE/PROJ/MYEXP');
     * % How many features do we have?
     * length(features)
     * % What is the name of features 1?
     * features(1)
     * </pre>
     * 
     * @param experiment The augmented code of the experiment to list the features for
     * @return Each row contains information about one feature. Currently the only information
     *         available is the feature name.
     */
    public static Object[][] listFeatures(String experiment)
    {
        checkLoggedIn();
        final List<Plate> experimentPlates = experimentToPlateMap.get(experiment);
        if (experimentPlates == null)
        {
            throw new RuntimeException("No experiment with that code found.");
        }
        if (experimentPlates.isEmpty())
        {
            return new Object[0][];
        }
        final List<FeatureVectorDatasetReference> featureDatasets =
                openbis.listFeatureVectorDatasets(experimentPlates);
        if (featureDatasets.isEmpty())
        {
            return new Object[0][];
        }
        final List<String> features = listAvailableFeatureCodes(featureDatasets);
        Object[][] result = new Object[features.size()][1];
        for (int i = 0; i < result.length; ++i)
        {
            result[i][0] = features.get(i);
        }
        return result;
    }

    @SuppressWarnings("deprecation")
    private static List<String> listAvailableFeatureCodes(
            final List<FeatureVectorDatasetReference> featureDatasets)
    {
        return openbis.listAvailableFeatureNames(Arrays.asList(featureDatasets.get(0)));
    }
    
    //
    // Data Sets
    //

    /**
     * Loads data sets for specified plate code. For each data set the path to the root of the data
     * set is returned. If it is possible the path points directly into the data set store. No data
     * is copied. Otherwise the data is retrieved from the data store server.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Load all data sets of plate P005 in space SPACE
     * dsinfo = loadDataSets('/SPACE/P005')
     * % Get the data set codes
     * dsinfo(:,1)
     * % Get root path of first data set (assuming there is at least one)
     * dsginfo(1,2)
     * </pre>
     * 
     * @param augmentedPlateCode The augmented plate code.
     * @return Each row contains information about one data set:
     *         <p>
     *         <code>{ data set code, data set root path  }</code>
     */
    public static Object[][] loadDataSets(String augmentedPlateCode)  {
        checkLoggedIn();
        Plate plateIdentifier = getPlate(augmentedPlateCode);

        List<IDataSetDss> dataSets = openbis.getDataSets(plateIdentifier);
        Object[][] result = new Object[dataSets.size()][];
        try
        {
            for (int i = 0; i < dataSets.size(); i++)
            {
                IDataSetDss dataSet = dataSets.get(i);
                File file = new File(dataSetsDir, dataSet.getCode());
                if (file.exists() == false)
                {
                    file = dataSet.getLinkOrCopyOfContents(null, dataSetsDir);
                }
                result[i] = new Object[] {dataSet.getCode(), file.getPath()};
            }
            return result;
        } catch (Exception ex)
        {
            throw new RuntimeException("Loading data sets for plate '" + augmentedPlateCode
                    + "' failed: " + ex, ex);
        }
    }

    /**
     * Uploads specified data set for specified plate. The data set code will be returned.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Upload data set /path/to/my-data-set with properties DESCRIPTION and NUMBER for 
     * % plate P005 in space SPACE
     * properties = {'DESCRIPTION' 'hello example'; 'NUMBER' 3.14}
     * datasetcode = uploadDataSet('/SPACE/P005', '/path/to/my-data-set', 'HCS_IMAGE', properties)
     * </pre>
     * 
     * @param augmentedPlateCode The augmented plate code.
     * @param dataSetFilePath Path to the data set file/folder to be uploaded.
     * @param dataSetType Data set type.
     * @param dataSetProperties A two dimensional array where the first column contains the property
     *            codes and the second column the corresponding property values.
     */
    public static Object uploadDataSet(String augmentedPlateCode, String dataSetFilePath,
            String dataSetType, Object[][] dataSetProperties)
    {
        checkLoggedIn();
        Plate plateIdentifier = getPlate(augmentedPlateCode);
        File dataSetFile = new File(dataSetFilePath);
        if (dataSetFile.exists() == false)
        {
            throw new RuntimeException("Unknown data set file path '" + dataSetFilePath + "'.");
        }
        try
        {
            HashMap<String, String> map = new HashMap<String, String>();
            for (Object[] objects : dataSetProperties)
            {
                if (objects.length == 2)
                {
                    map.put(objects[0].toString(), objects[1].toString());
                }
            }
            IDataSetDss dataSet =
                    openbis.putDataSet(plateIdentifier, dataSetFile, new NewDataSetMetadataDTO(
                            dataSetType, map));
            return dataSet.getCode();
        } catch (Exception ex)
        {
            throw new RuntimeException("Couldn't upload data set for plate '" + augmentedPlateCode
                    + "'.", ex);
        }
    }

    public static Object testProperties(Properties properties)
    {
        return properties.toString();
    }
    //
    // Images
    //

    /**
     * Loads the TIFF images for the given well location, all tiles and all channels and stores them
     * in temporary files. The temporary files will be removed automatically when the Java Virtual
     * Machine exits.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Load the images for all channels of well B10 of plate P005 in space SPACE
     * imginfo = OpenBISScreeningML.loadImages('/SPACE/P005', 2, 10)
     * % Get the plate-well descriptions of all locations
     * imginfo(2,:,3)
     * % Show the third image (assuming there are at least three images)
     * imtool(imginfo(1,3))
     * </pre>
     * 
     * @param plate The augmented plate code
     * @param row The row in the plate to get the images for
     * @param col The column in the plate to get the images for
     * @return <code>{ names of TIFF files, image annotation }</code>
     *         <p>
     *         Each of <code>names of TIFF files</code> and <code>image annotation</code> is a
     *         vector of length of the number of images.
     *         <p>
     *         <code>image annotation</code> contains
     *         <code>{ channel name, tile number, plate well description, 
     *         plate augmented code, plate perm id, plate space code, plate code, row, column, 
     *         experiment augmented code, experiment perm id, experiment space code, 
     *         experiment project code, experiment code, data set code }</code>
     */
    public static Object[][][] loadImages(String plate, int row, int col)
    {
        return loadImages(plate, row, col, (String[]) null);
    }

    /**
     * Loads the TIFF images for the given well location, tile number, and all channels and stores
     * them in temporary files. The temporary files will be removed automatically when the Java
     * Virtual Machine exits.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Load the images for all channels of well B10 and tile 3 of plate P005 in space SPACE
     * imginfo = OpenBISScreeningML.loadImages('/SPACE/P005', 2, 10, 3)
     * % Get the plate-well descriptions of all locations
     * imginfo(2,:,3)
     * % Show the third image (assuming there are at least three images)
     * imtool(imginfo(1,3))
     * </pre>
     * 
     * @param plate The augmented plate code
     * @param row The row in the plate to get the images for
     * @param col The column in the plate to get the images for
     * @param tile The tile number. Starts with 0. 
     * @return <code>{ names of TIFF files, image annotation }</code>
     *         <p>
     *         Each of <code>names of TIFF files</code> and <code>image annotation</code> is a
     *         vector of length of the number of images.
     *         <p>
     *         <code>image annotation</code> contains
     *         <code>{ channel name, tile number, plate well description, 
     *         plate augmented code, plate perm id, plate space code, plate code, row, column, 
     *         experiment augmented code, experiment perm id, experiment space code, 
     *         experiment project code, experiment code, data set code }</code>
     */
    public static Object[][][] loadImages(String plate, int row, int col, int tile)
    {
        return loadImages(plate, row, col, tile, (String[]) null);
    }

    /**
     * Loads the TIFF images for the given well location, list of channels, and all tiles and stores
     * them in temporary files. The temporary files will be removed automatically when the Java
     * Virtual Machine exits.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Load the images for channel DAPI of well H10 of plate P005 in space SPACE
     * imginfo=OpenBISScreeningML.loadImages('/SPACE/P005', 8, 10, 'DAPI')
     * % Get the channel names and tile numbers of all locations
     * imginfo(2,:,1:2)
     * % Show the second image (assuming there are at least two images)
     * imtool(imginfo(1,2))
     * </pre>
     * 
     * @param plate The augmented plate code
     * @param row The row in the plate to get the images for
     * @param col The column in the plate to get the images for
     * @param channels The names of the channels to get the images for
     * @return <code>{ names of TIFF files, image annotation }</code>
     *         <p>
     *         Each of <code>names of TIFF files</code> and <code>image annotation</code> is a
     *         vector of length of the number of images.
     *         <p>
     *         <code>image annotation</code> contains
     *         <code>{ channel name, tile number, plate well description, 
     *         plate augmented code, plate perm id, plate space code, plate code, row, column, 
     *         experiment augmented code, experiment perm id, experiment space code, 
     *         experiment project code, experiment code, data set code }</code>
     */
    public static Object[][][] loadImages(String plate, int row, int col, String[] channels)
    {
        return loadImages(plate, row, col, channels, new ITileNumberIterable()
            {
                private int maximumNumberOfTiles;

                public void setMaximumNumberOfTiles(int numberOfTiles)
                {
                    this.maximumNumberOfTiles = numberOfTiles;
                }

                public int getMaximumNumberOfTiles()
                {
                    return maximumNumberOfTiles;
                }

                public Iterator<Integer> iterator()
                {
                    return new Iterator<Integer>()
                        {
                            private int index;
                            
                            public boolean hasNext()
                            {
                                return index < maximumNumberOfTiles;
                            }

                            public Integer next()
                            {
                                return index++;
                            }

                            public void remove()
                            {
                                throw new UnsupportedOperationException();
                            }
                        };
                }
            });
    }

    /**
     * Loads the TIFF images for the given well location, tile number, and list of channels and
     * stores them in temporary files. The temporary files will be removed automatically when the
     * Java Virtual Machine exits.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Load the images for channel DAPI of well H10 and tile 3 of plate P005 in space SPACE
     * imginfo=OpenBISScreeningML.loadImages('/SPACE/P005', 8, 10, 3, 'DAPI')
     * % Get the channel names of all locations
     * imginfo(2,:,1)
     * % Show the second image (assuming there are at least two images)
     * imtool(imginfo(1,2))
     * </pre>
     * 
     * @param plate The augmented plate code
     * @param row The row in the plate to get the images for
     * @param col The column in the plate to get the images for
     * @param tile The tile number. Starts with 0. 
     * @param channels The names of the channels to get the images for
     * @return <code>{ names of TIFF files, image annotation }</code>
     *         <p>
     *         Each of <code>names of TIFF files</code> and <code>image annotation</code> is a
     *         vector of length of the number of images.
     *         <p>
     *         <code>image annotation</code> contains
     *         <code>{ channel name, tile number, plate well description, 
     *         plate augmented code, plate perm id, plate space code, plate code, row, column, 
     *         experiment augmented code, experiment perm id, experiment space code, 
     *         experiment project code, experiment code, data set code }</code>
     */
    public static Object[][][] loadImages(String plate, int row, int col, final int tile,
            String[] channels)
    {
        return loadImages(plate, row, col, channels, new ITileNumberIterable()
            {
                public void setMaximumNumberOfTiles(int numberOfTiles)
                {
                    if (tile >= numberOfTiles)
                    {
                        throw new IllegalArgumentException("Tile number " + tile
                                + " is not less than number of tiles " + numberOfTiles + ".");
                    }
                }

                public int getMaximumNumberOfTiles()
                {
                    return 1;
                }

                public Iterator<Integer> iterator()
                {
                    return new Iterator<Integer>()
                        {
                            private boolean delivered;

                            public boolean hasNext()
                            {
                                return delivered == false;
                            }

                            public Integer next()
                            {
                                delivered = true;
                                return tile;
                            }

                            public void remove()
                            {
                                throw new UnsupportedOperationException();
                            }
                        };
                }
            });
    }
    
    public static Object[][][] loadImages(String plate, int row, int col, String[] channels,
            ITileNumberIterable tileNumberIterable)
    {
        checkLoggedIn();
        final Plate plateId = getPlate(plate);
        final List<ImageDatasetReference> imageDatasets =
                openbis.listRawImageDatasets(Arrays.asList(plateId));
        final List<ImageDatasetMetadata> meta = openbis.listImageMetadata(imageDatasets);
        if (meta.isEmpty())
        {
            return new Object[][][]
                { new Object[0][], new Object[0][] };
        }
        final List<String> imageChannels;
        if (channels == null || channels.length == 0)
        {
            imageChannels = getChannelCodes(meta);
        } else
        {
            imageChannels = Arrays.asList(channels);
        }
        final List<ImageReferenceAndFile> imageReferencesAndFiles =
            new ArrayList<ImageReferenceAndFile>(imageDatasets.size());
        final Object[][][] result = new Object[2][][];
        tileNumberIterable.setMaximumNumberOfTiles(meta.get(0).getNumberOfTiles());
        int numberOfTiles = tileNumberIterable.getMaximumNumberOfTiles();
        result[0] = new Object[imageDatasets.size() * imageChannels.size() * numberOfTiles][1];
        result[1] = new Object[imageDatasets.size() * imageChannels.size() * numberOfTiles][15];
        int dsIdx = 0;
        int resultIdx = 0;
        for (ImageDatasetReference ds : imageDatasets)
        {
            for (String channel : imageChannels)
            {
                for (Integer tile : tileNumberIterable)
                {
                    final PlateImageReference ref =
                            new PlateImageReference(row, col, tile, channel, ds);
                    final File imageFile = createImageFileName(plateId, ref);
                    imageReferencesAndFiles.add(new ImageReferenceAndFile(ref, imageFile));
                    result[0][resultIdx][0] = imageFile.getPath();
                    final Object[] annotations =
                            new Object[]
                                { channel, tile,
                                        createPlateWellDescription(ds.getPlate(), row, col),
                                        ds.getPlate().getAugmentedCode(),
                                        ds.getPlate().getPermId(), ds.getPlate().tryGetSpaceCode(),
                                        ds.getPlate().getPlateCode(), row, col,
                                        ds.getExperimentIdentifier().getAugmentedCode(),
                                        ds.getExperimentIdentifier().getPermId(),
                                        ds.getExperimentIdentifier().getSpaceCode(),
                                        ds.getExperimentIdentifier().getProjectCode(),
                                        ds.getExperimentIdentifier().getExperimentCode(),
                                        ds.getPermId(), };
                    System.arraycopy(annotations, 0, result[1][resultIdx], 0, annotations.length);
                    resultIdx++;
                }
            }
            dsIdx++;
        }
        try
        {
            loadImages(imageReferencesAndFiles);
        } catch (IOException ex)
        {
            throw new RuntimeException(ex);
        }
        return result;
    }
    
    /**
     * Saves images for a given list of image references (given by data set code, well position,
     * channel and tile) and files.
     * 
     * @throws IOException when reading images from the server or writing them to the files fails
     */
    private static void loadImages(List<ImageReferenceAndFile> imageReferencesAndFiles)
            throws IOException
    {
        List<PlateImageReference> imageReferences = new ArrayList<PlateImageReference>();
        final Map<PlateImageReference, ImageReferenceAndFile> imageRefToFileMap =
                new HashMap<PlateImageReference, ImageReferenceAndFile>();
        for (ImageReferenceAndFile imageReferenceAndFile : imageReferencesAndFiles)
        {
            PlateImageReference imageReference = imageReferenceAndFile.getImageReference();
            File file = loadedImages.get(imageReference);
            if (file == null)
            {
                imageReferences.add(imageReference);
                imageRefToFileMap.put(imageReference, imageReferenceAndFile);
            }
        }
        try
        {
            openbis.loadImages(imageReferences, new IImageOutputStreamProvider()
                {
                    public OutputStream getOutputStream(PlateImageReference imageReference)
                            throws IOException
                    {
                        return imageRefToFileMap.get(imageReference).open();
                    }
                }, false);
        } finally
        {
            Collection<ImageReferenceAndFile> values = imageRefToFileMap.values();
            for (ImageReferenceAndFile imageReferenceAndFile : values)
            {
                imageReferenceAndFile.close();
                PlateImageReference imageReference = imageReferenceAndFile.getImageReference();
                loadedImages.put(imageReference, imageReferenceAndFile.getImageFile());
            }
        }
    }
    
    private static File createImageFileName(Plate plate, PlateImageReference image)
    {
        final WellPosition well = image.getWellPosition();
        File imageDir = new File(temporarySessionDir, "images");
        imageDir.mkdirs();
        final File f =
                new File(imageDir, "img_" + plate.getPlateCode() + "_"
                        + image.getDatasetCode() + "_row" + well.getWellRow() + "_col"
                        + well.getWellColumn() + "_" + image.getChannel() + "_tile"
                        + image.getTile() + ".tiff");
        f.deleteOnExit();
        return f;
    }
    
    //
    // Feature matrix
    //

    /**
     * Returns the feature matrix of all features for all locations in <var>experiment</var> (a
     * location is one well position in one feature vector data set) connected to <var>gene</var> in
     * <code>[0]</code>, location annotations in <code>[1]</code> and feature annotation in
     * <code>[2]</code>.
     * <p>
     * One row in the matrix corresponds to one location (i.e. one well and one feature vector
     * dataset), one column corresponds to one feature.
     * <p>
     * Matlab example:
     * 
     * <pre>
     * % Get feature matrix for experiment /SPACE/PROJ/MYEXP for locations connected to GENENAME
     * fmatrix = OpenBISScreeningML.getFeatureMatrix('/SPACE/PROJ/MYEXP', 'GENENAME');
     * % Get the feature vector for the second location (assuming there are at least two locations)
     * loc2 = fmatrix(1,2,:)
     * % Get the values of the fifth feature for all locations (assuming there are at least 5 features)
     * feature5 = fmatrix(1,:,5)
     * % What are the features?
     * featureNames = fmatrix(3,:)
     * % Get the plate-well descriptions of the locations
     * locationDescriptions = fmatrix(2,:,1)
     * </pre>
     * 
     * @param experiment The augmented experiment code
     * @param gene The gene name as stored as material code in openBIS
     * @return <code>{ feature matrix, annotations per location, feature names }</code> where
     *         <code>annotations per location</code> contain:
     *         <p>