Make ready for automatic merge.

build.gradle

@@ -28,6 +28,7 @@ repositories {
 
 dependencies {
     // Use JUnit test framework
+    compile group: 'commons-cli', name: 'commons-cli', version: '1.4'
     testImplementation('org.junit.jupiter:junit-jupiter:5.4.2')
 
     // Logging

src/main/java/de/tudresden/inf/mci/brailleplot/App.java

 package de.tudresden.inf.mci.brailleplot;
 
-import de.tudresden.inf.mci.brailleplot.configparser.PrinterProperty;
+import de.tudresden.inf.mci.brailleplot.commandline.CommandLineParser;
+import de.tudresden.inf.mci.brailleplot.commandline.SettingType;
+import de.tudresden.inf.mci.brailleplot.commandline.SettingsReader;
+import de.tudresden.inf.mci.brailleplot.commandline.SettingsWriter;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+
+import java.util.Optional;
 import java.util.concurrent.ConcurrentLinkedDeque;
 
 /**
@@ -107,10 +113,17 @@ public final class App {
             mLogger.info("Application started");
 
             // Parse command line parameters
+            CommandLineParser cliParser = new CommandLineParser();
+            SettingsWriter settings = cliParser.parse(args);
+            SettingsReader settingsReader = settings;
 
 
             // If requested, print help and exit
-
+            Optional<Boolean> printHelp = settingsReader.isTrue(SettingType.DISPLAY_HELP);
+            if (printHelp.isPresent() && printHelp.get()) {
+                cliParser.printHelp();
+                return EXIT_SUCCESS;
+            }
 
             // Parse csv data
 

src/main/java/de/tudresden/inf/mci/brailleplot/commandline/CommandLineParser.java

+package de.tudresden.inf.mci.brailleplot.commandline;
+
+import org.apache.commons.cli.CommandLine;
+import org.apache.commons.cli.DefaultParser;
+import org.apache.commons.cli.HelpFormatter;
+import org.apache.commons.cli.Options;
+import org.apache.commons.cli.ParseException;
+
+/**
+ * Performs command line parsing and creates a {@link Settings} object.
+ * @author Georg Graßnick
+ * @version 2019.05.31
+ */
+public class CommandLineParser {
+
+    private Options mOptions;
+
+    public CommandLineParser() {
+        setupOptions();
+    }
+
+    private void setupOptions() {
+        mOptions = new Options();
+        mOptions.addOption("h", SettingType.DISPLAY_HELP.toString(), false, "Print help and exit")
+                .addOption("c", SettingType.CSV_LOCATION.toString(), true, "Path to CSV")
+                .addOption("s", SettingType.SEMANTIC_MAPPING.toString(), true, "Literal for semantic mapping")
+                .addOption("p", SettingType.PRINTER_CONFIG_PATH.toString(), true, "path to printer configuration file");
+    }
+
+    /**
+     * Parse command line parameters.
+     * @param args The arguments from the commandline.
+     * @return A {@link Settings} object that represents the values from the command line parameters.
+     * @throws ParsingException On any underlying error.
+     */
+    public final Settings parse(final String[] args) throws ParsingException {
+
+        org.apache.commons.cli.CommandLineParser parser = new DefaultParser();
+        CommandLine cmdLine;
+        try {
+            cmdLine = parser.parse(mOptions, args);
+        } catch (ParseException pe) {
+            throw new ParsingException("Could not parse command line", pe);
+        }
+        return new Settings(cmdLine);
+    }
+
+    /**
+     * Print usage information to the command line.
+     */
+    public final void printHelp() {
+        HelpFormatter formatter = new HelpFormatter();
+        String headerForOptions = "Convert csv into braille";
+        String footerForOptions = "Report Issues to Leonard Kupper";
+
+        formatter.printHelp("braillegraphics", headerForOptions, mOptions, footerForOptions, true);
+    }
+}

src/main/java/de/tudresden/inf/mci/brailleplot/commandline/ParsingException.java

+package de.tudresden.inf.mci.brailleplot.commandline;
+
+/**
+ * Exception class.
+ * Indicates, some error has occurred while parsing the command line parameters.
+ * Most likely created by malformed user input.
+ * @author Georg Graßnick
+ * @version 2019.05.31
+ */
+public class ParsingException extends Exception {
+
+    public ParsingException() { }
+
+    public ParsingException(final String message) {
+        super(message);
+    }
+
+    public ParsingException(final Throwable cause) {
+        super(cause);
+    }
+
+    public ParsingException(final String message, final Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/de/tudresden/inf/mci/brailleplot/commandline/SettingType.java

+package de.tudresden.inf.mci.brailleplot.commandline;
+
+/**
+ * Represents all possible parsed options parsed from the command line.
+ * @author Georg Graßnick
+ * @version 2019.05.31
+ */
+public enum SettingType {
+
+    DISPLAY_HELP("help"),
+    CSV_LOCATION("csv-path"),
+    PRINTER_CONFIG_PATH("printer-config-path"),
+    SEMANTIC_MAPPING("semantic-mapping");
+
+    private final String mName;
+
+    SettingType(final String name) {
+        this.mName = name;
+    }
+
+    static SettingType fromString(final String s) {
+        switch (s) {
+            case "help":
+                return DISPLAY_HELP;
+            case "csv-path":
+                return  CSV_LOCATION;
+            case "printer-config-path":
+                return PRINTER_CONFIG_PATH;
+            case "semantic-mapping":
+                return SEMANTIC_MAPPING;
+            default:
+                throw new IllegalArgumentException("Setting not available");
+        }
+    }
+
+    public String toString() {
+        return mName;
+    }
+}

src/main/java/de/tudresden/inf/mci/brailleplot/commandline/Settings.java

+package de.tudresden.inf.mci.brailleplot.commandline;
+
+import org.apache.commons.cli.CommandLine;
+import org.apache.commons.cli.Option;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Optional;
+
+/**
+ * Encapsulates Settings for the Application from the command line.
+ * @author Georg Graßnick
+ * @version 2019.05.31
+ */
+public final class Settings implements SettingsReader, SettingsWriter {
+
+    private Map<SettingType, String> mSettings;
+
+    private final Logger mLogger = LoggerFactory.getLogger(this.getClass());
+
+    private static final String BOOL_TRUE = Boolean.toString(true);
+    private static final String BOOL_FALSE = Boolean.toString(false);
+
+    /**
+     * Constructor.
+     * @param cmdLine CommandLine object to take information from.
+     */
+    Settings(final CommandLine cmdLine) {
+        mSettings = new HashMap<>();
+        setup(cmdLine);
+    }
+
+
+    /**
+     * Populates the Settings class with arguments from the command line.
+     * @param cmdLine {@link CommandLine} object to take take settings from.
+     */
+    private void setup(final CommandLine cmdLine) {
+        for (Iterator<Option> it = cmdLine.iterator(); it.hasNext();) {
+            Option o = it.next();
+            if (o.hasArg()) {
+                SettingType type = SettingType.fromString(o.getLongOpt());
+                mSettings.put(type, o.getValue());
+                mLogger.trace("Added string \"{}\" with value \"{}\"", type, o.getValue());
+            } else {
+                mSettings.put(SettingType.fromString(o.getLongOpt()), BOOL_TRUE);
+                mLogger.trace("Added flag \"{}\" set to \"{}\"", SettingType.fromString(o.getLongOpt()), BOOL_TRUE);
+            }
+        }
+    }
+
+    /**
+     * Check if a specific setting is set.
+     * @param setting The requested setting.
+     * @return true if the parameter is set, else false.
+     */
+    public boolean isPresent(final SettingType setting) {
+        return mSettings.containsKey(setting);
+    }
+
+    /**
+     * Get the value of a setting, if set.
+     * @param setting The requested Setting to request the value for.
+     * @return {@link Optional}{@literal <String>} if setting is set, or {@link Optional#empty()} if the requested setting
+     * was not specified by the user.
+     * Use {@link Settings#isPresent(SettingType)} to check the value of a boolean parameter.
+     */
+    public Optional<String> getSetting(final SettingType setting) {
+        if (!mSettings.containsKey(setting)) {
+            return Optional.empty();
+        }
+        return Optional.of(mSettings.get(setting));
+    }
+
+    /**
+     * Get the boolean value of a setting, if set.
+     * @param setting The requested Setting to request the value for.
+     * @return {@link Optional}{@literal <Boolean>} if setting is set, or {@link Optional#empty()} if the requested setting
+     * was not specified by the user.
+     */
+    public Optional<Boolean> isTrue(final SettingType setting) {
+        if (!mSettings.containsKey(setting)) {
+            return Optional.empty();
+        }
+
+        if (mSettings.get(setting).equals(BOOL_TRUE)) {
+            return Optional.of(true);
+        } else {
+            return Optional.of(false);
+        }
+    }
+
+    /**
+     * Set the value of a setting.
+     * @param setting {@link SettingType} the setting to be changed.
+     * @param value {@link String} The value to set.
+     */
+    public void setSetting(final SettingType setting, final String value) {
+        mSettings.replace(setting, value);
+    }
+
+    /**
+     * Set the value of a setting to a specific {@link Boolean}.
+     * @param setting {@link SettingType} the setting to be changed.
+     * @param isTrue {@link String} The value to set.
+     */
+    public void setSetting(final SettingType setting, final Boolean isTrue) {
+        if (isTrue) {
+            mSettings.replace(setting, BOOL_TRUE);
+        } else {
+            mSettings.replace(setting, BOOL_FALSE);
+        }
+    }
+
+    /**
+     * Delete the set value of a setting, if it is set.
+     * @param setting {@link SettingType} the setting to be removed.
+     */
+    public void deleteSettingValue(final SettingType setting) {
+            mSettings.remove(setting);
+    }
+
+}

src/main/java/de/tudresden/inf/mci/brailleplot/commandline/SettingsReader.java

+package de.tudresden.inf.mci.brailleplot.commandline;
+
+import java.util.Optional;
+
+/**
+ * Supplies an interface for reading settings.
+ * @author Georg Graßnick
+ * @version 2019.06.01
+ */
+public interface SettingsReader {
+
+    Optional<String> getSetting(SettingType setting);
+    boolean isPresent(SettingType setting);
+    Optional<Boolean> isTrue(SettingType setting);
+}

src/main/java/de/tudresden/inf/mci/brailleplot/commandline/SettingsWriter.java

+package de.tudresden.inf.mci.brailleplot.commandline;
+
+/**
+ * Implementing classes are guaranteed to support manipulating settings.
+ * Currently, the implementation is not thread safe!
+ * @author Georg Graßnick
+ * @version 2019.06.01
+ */
+public interface SettingsWriter extends SettingsReader {
+
+    void setSetting(SettingType setting, String value);
+    void setSetting(SettingType setting, Boolean isTrue);
+    void deleteSettingValue(SettingType setting);
+}

src/main/java/de/tudresden/inf/mci/brailleplot/commandline/package-info.java

+/**
+ * Responsible for command line parsing and the creation of an {@link de.tudresden.inf.mci.brailleplot.commandline.Settings} object
+ * which can be queried by {@link de.tudresden.inf.mci.brailleplot.commandline.SettingsReader}
+ * and manipulated by {@link de.tudresden.inf.mci.brailleplot.commandline.SettingsWriter}.
+ */
+package de.tudresden.inf.mci.brailleplot.commandline;

src/test/java/de/tudresden/inf/mci/brailleplot/commandline/CommandLineParserTest.java

+package de.tudresden.inf.mci.brailleplot.commandline;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.fail;
+
+/**
+ * Tests the CommandlineParser and the querying of parameters of the Settings object.
+ */
+class CommandLineParserTest {
+
+    private CommandLineParser commandLineParser = new CommandLineParser();
+
+    @Test
+    void testParseLegalArgs() {
+        String[] args = {"-h", "--csv-path", "foobar"};
+        Assertions.assertDoesNotThrow(() -> {commandLineParser.parse(args);});
+    }
+
+    @Test
+    void testIllegalArgs() {
+        String[] args = {"-h --foobar"};
+        Assertions.assertThrows(ParsingException.class, () -> {commandLineParser.parse(args);});
+    }
+
+    @Test
+    void testEmptyArgs() {
+        String[] args = {""};
+        Assertions.assertDoesNotThrow(() -> {commandLineParser.parse(args);});
+    }
+
+    @Test
+    void testBoolFlagRecognized() {
+        String[] args = {"-h"};
+        SettingsReader settings;
+        try {
+            settings = commandLineParser.parse(args);
+        } catch (ParsingException pe) {
+            fail();
+            return; // Never executed, satisfy compiler
+        }
+        Optional<Boolean> flag = settings.isTrue(SettingType.DISPLAY_HELP);
+        Assertions.assertTrue(flag.isPresent());
+        Assertions.assertTrue(flag.get());
+    }
+
+    @Test
+    void testBoolFlagCorrectlyNotRecognized() {
+        String[] args = {""};
+        SettingsReader settings;
+        try {
+            settings = commandLineParser.parse(args);
+        } catch (ParsingException pe) {
+            fail();
+            return; // Never executed, satisfy compiler
+        }
+        Optional<Boolean> flag = settings.isTrue(SettingType.DISPLAY_HELP);
+        Assertions.assertFalse(flag.isPresent());
+    }
+
+    @Test
+    void testParameterRecognized() {
+        final String param = "xyz";
+        String[] args = {"--csv-path", param};
+        SettingsReader settings;
+        try {
+            settings = commandLineParser.parse(args);
+        } catch (ParsingException pe) {
+            fail();
+            return; // Never executed, satisfy compiler
+        }
+        Optional<String> flag = settings.getSetting(SettingType.CSV_LOCATION);
+        Assertions.assertTrue(flag.isPresent());
+        Assertions.assertTrue(flag.get().equals(param));
+    }
+
+    @Test
+    void testParameterCorrectlyNotRecognized() {
+        String[] args = {""};
+        SettingsReader settings;
+        try {
+            settings = commandLineParser.parse(args);
+        } catch (ParsingException pe) {
+            fail();
+            return; // Never executed, satisfy compiler
+        }
+        Optional<String> flag = settings.getSetting(SettingType.CSV_LOCATION);
+        Assertions.assertFalse(flag.isPresent());
+    }
+}
+