Feature: Render answer sets as excel workbooks (xlsx files)

build.gradle

@@ -44,6 +44,8 @@ dependencies {
 	implementation group: 'org.apache.commons', name: 'commons-collections4', version: '4.1'
 	implementation group: 'org.apache.commons', name: 'commons-lang3',        version: '3.6'
 	implementation group: 'org.reflections',    name: 'reflections',          version: '0.9.11'
+	implementation group: 'org.apache.poi',     name: 'poi',                  version: '4.1.1'
+	implementation group: 'org.apache.poi',     name: 'poi-ooxml',            version: '4.1.1'
 
 	testImplementation group: 'junit', name: 'junit', version: '4.12'
 }
@@ -85,16 +87,16 @@ task bundledJar(type: Jar) {
 	}
 
 	archiveFileName = "${project.name}-bundled.jar"
-
+	
 	/*
-	 * In order to make sure wo don't overwrite NOTICE and LICENSE files coming from dependency
+	 * In order to make sure we don't overwrite NOTICE and LICENSE files coming from dependency
 	 * jars with each other, number them while copying
 	 */
 	int i = 1
-	rename { name -> name.equals("NOTICE.txt") ? "NOTICE." + (i++) + ".txt" :  null }
+	rename { name -> (name.equals("NOTICE.txt") || name.equals("NOTICE")) ? "NOTICE." + (i++) + ".txt" :  null }
 
 	int j = 1
-	rename { name -> name.equals("LICENSE.txt") ? "LICENSE." + (j++) + ".txt" : null }
+	rename { name -> (name.equals("LICENSE.txt") || name.equals("LICENSE")) ? "LICENSE." + (j++) + ".txt" : null }
 
 	with jar
 }

src/main/java/at/ac/tuwien/kr/alpha/AnswerSetToXlsxWriter.java

@@ -0,0 +1,60 @@
+package at.ac.tuwien.kr.alpha;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
+import java.util.function.BiConsumer;
+
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+
+import at.ac.tuwien.kr.alpha.api.mapper.AnswerSetToObjectMapper;
+import at.ac.tuwien.kr.alpha.api.mapper.impl.AnswerSetToWorkbookMapper;
+import at.ac.tuwien.kr.alpha.common.AnswerSet;
+
+public class AnswerSetToXlsxWriter implements BiConsumer<Integer, AnswerSet> {
+
+	private String targetBasePath;
+	private AnswerSetToObjectMapper<Workbook> answerSetMapper;
+
+	public AnswerSetToXlsxWriter(String targetBasePath) {
+		this.targetBasePath = targetBasePath;
+		this.answerSetMapper = new AnswerSetToWorkbookMapper();
+	}
+
+	@Override
+	public void accept(Integer num, AnswerSet as) {
+		try {
+			Path outputPath = Paths.get(this.targetBasePath + "." + num + ".xlsx");
+			OutputStream os = Files.newOutputStream(outputPath, StandardOpenOption.CREATE, StandardOpenOption.WRITE, StandardOpenOption.TRUNCATE_EXISTING);
+			Workbook wb = this.answerSetMapper.mapFromAnswerSet(as);
+			wb.write(os);
+			wb.close();
+			os.close();
+			System.out.println("Answer set written to file " + outputPath.toString());
+		} catch (IOException ex) {
+			System.err.println("Failed writing answer set as xlsx file! (" + ex.getMessage() + ")");
+		}
+	}
+
+	public static void writeUnsatInfo(Path path) throws IOException {
+		Workbook workbook = new XSSFWorkbook();
+		// first, create a worksheet for 0-arity predicates
+		Sheet sheet = workbook.createSheet("Unsatisfiable");
+		Row row = sheet.createRow(0);
+		Cell cell = row.createCell(0);
+		cell.setCellValue("Input is unsatisfiable - No answer sets!");
+		sheet.autoSizeColumn(0);
+		OutputStream os = Files.newOutputStream(path, StandardOpenOption.CREATE, StandardOpenOption.WRITE, StandardOpenOption.TRUNCATE_EXISTING);
+		workbook.write(os);
+		workbook.close();
+		os.close();
+	}
+
+}

src/main/java/at/ac/tuwien/kr/alpha/Main.java

@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2016-2019, the Alpha Team.
+ * Copyright (c) 2016-2020, the Alpha Team.
  * All rights reserved.
  *
  * Additional changes made by Siemens.
@@ -29,7 +29,9 @@
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.Paths;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.BiConsumer;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -38,6 +40,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import at.ac.tuwien.kr.alpha.api.Alpha;
 import at.ac.tuwien.kr.alpha.common.AnswerSet;
 import at.ac.tuwien.kr.alpha.common.Program;
 import at.ac.tuwien.kr.alpha.config.AlphaConfig;
@@ -98,9 +101,29 @@ private static void computeAndConsumeAnswerSets(Alpha alpha, InputConfig inputCf
 
 		if (!alpha.getConfig().isQuiet()) {
 			AtomicInteger counter = new AtomicInteger(0);
-			stream.forEach(as -> System.out.println("Answer set " + counter.incrementAndGet() + ":" + System.lineSeparator() + as.toString()));
+			final BiConsumer<Integer, AnswerSet> answerSetHandler;
+			BiConsumer<Integer, AnswerSet> stdoutPrinter = (n, as) -> {
+				System.out.println("Answer set " + Integer.toString(n) + ":" + System.lineSeparator() + as.toString());
+			};
+			if (inputCfg.isWriteAnswerSetsAsXlsx()) {
+				BiConsumer<Integer, AnswerSet> xlsxWriter = new AnswerSetToXlsxWriter(inputCfg.getAnswerSetFileOutputPath());
+				answerSetHandler = stdoutPrinter.andThen(xlsxWriter);
+			} else {
+				answerSetHandler = stdoutPrinter;
+			}
+			stream.forEach(as -> {
+				int cnt = counter.incrementAndGet();
+				answerSetHandler.accept(cnt, as);
+			});
 			if (counter.get() == 0) {
 				System.out.println("UNSATISFIABLE");
+				if (inputCfg.isWriteAnswerSetsAsXlsx()) {
+					try {
+						AnswerSetToXlsxWriter.writeUnsatInfo(Paths.get(inputCfg.getAnswerSetFileOutputPath() + ".UNSAT.xlsx"));
+					} catch (IOException ex) {
+						System.err.println("Failed writing unsat file!");
+					}
+				}
 			} else {
 				System.out.println("SATISFIABLE");
 			}

src/main/java/at/ac/tuwien/kr/alpha/Alpha.java → src/main/java/at/ac/tuwien/kr/alpha/api/Alpha.java

@@ -25,8 +25,9 @@
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-package at.ac.tuwien.kr.alpha;
+package at.ac.tuwien.kr.alpha.api;
 
+import at.ac.tuwien.kr.alpha.Util;
 import at.ac.tuwien.kr.alpha.common.AnswerSet;
 import at.ac.tuwien.kr.alpha.common.AtomStore;
 import at.ac.tuwien.kr.alpha.common.AtomStoreImpl;

src/main/java/at/ac/tuwien/kr/alpha/api/mapper/AnswerSetToObjectMapper.java

@@ -0,0 +1,41 @@
+/**
+ * Copyright (c) 2020, the Alpha Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1) Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2) Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package at.ac.tuwien.kr.alpha.api.mapper;
+
+import at.ac.tuwien.kr.alpha.common.AnswerSet;
+
+/**
+ * Copyright (c) 2020, the Alpha Team.
+ * 
+ * Interface definition for an adapter that maps from an {@link AnswerSet} to an instance of the implementation's generic type T.
+ * 
+ * @param <T> the type to which to map answer sets
+ */
+public interface AnswerSetToObjectMapper<T> {
+
+	T mapFromAnswerSet(AnswerSet answerSet);
+
+}

src/main/java/at/ac/tuwien/kr/alpha/api/mapper/impl/AnswerSetToWorkbookMapper.java

@@ -0,0 +1,138 @@
+/**
+ * Copyright (c) 2020, the Alpha Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1) Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2) Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package at.ac.tuwien.kr.alpha.api.mapper.impl;
+
+import java.util.List;
+
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.CellStyle;
+import org.apache.poi.ss.usermodel.FillPatternType;
+import org.apache.poi.ss.usermodel.Font;
+import org.apache.poi.ss.usermodel.IndexedColors;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import at.ac.tuwien.kr.alpha.api.mapper.AnswerSetToObjectMapper;
+import at.ac.tuwien.kr.alpha.common.AnswerSet;
+import at.ac.tuwien.kr.alpha.common.Predicate;
+import at.ac.tuwien.kr.alpha.common.atoms.Atom;
+import at.ac.tuwien.kr.alpha.common.terms.Term;
+
+/**
+ * Implementation of {@link AnswerSetToObjectMapper} that generates an office open xml workbook ("excel file") from a given answer set.
+ * 
+ * Copyright (c) 2020, the Alpha Team.
+ */
+public class AnswerSetToWorkbookMapper implements AnswerSetToObjectMapper<Workbook> {
+
+	private static final Logger LOGGER = LoggerFactory.getLogger(AnswerSetToWorkbookMapper.class);
+
+	/**
+	 * Creates an xlsx workbook containing all the atoms from the given {@link AnswerSet} with one sheet per predicate. All predicates with arity 0 are listed
+	 * in a special sheet called "flags". Caution, potential resource leak: note that the returned workbook needs to be closed by the caller once it has been
+	 * processed (written to file etc).
+	 */
+	@Override
+	public Workbook mapFromAnswerSet(AnswerSet answerSet) {
+		LOGGER.debug("Start mapping answer set to workbook");
+		Workbook workbook = new XSSFWorkbook();
+		// create cell style for header cells
+		CellStyle headerStyle = this.createHeaderStyle(workbook);
+
+		// first, create a worksheet for 0-arity predicates
+		Sheet flags = this.createSheetWithHeader(workbook, headerStyle, "Flags", "Flags");
+		Sheet currentPredicateSheet;
+		String[] headerContent;
+		for (Predicate pred : answerSet.getPredicates()) {
+			if (pred.getArity() == 0) {
+				this.writeAtomToSheet(flags, answerSet.getPredicateInstances(pred).first());
+			} else {
+				headerContent = new String[pred.getArity()];
+				for (int i = 0; i < headerContent.length; i++) {
+					headerContent[i] = "Attribute " + Integer.toString(i + 1);
+				}
+				currentPredicateSheet = this.createSheetWithHeader(workbook, headerStyle, pred.getName() + "_" + pred.getArity(), headerContent);
+				for (Atom atom : answerSet.getPredicateInstances(pred)) {
+					this.writeAtomToSheet(currentPredicateSheet, atom);
+				}
+			}
+		}
+		return workbook;
+	}
+
+	private void writeAtomToSheet(Sheet sheet, Atom atom) {
+		int rownum = -1;
+		if (sheet.getLastRowNum() == 0 && sheet.getRow(0) == null) {
+			// sheet is empty, start at row zero
+			rownum = 0;
+		} else {
+			rownum = sheet.getLastRowNum() + 1;
+		}
+		Row atomRow = sheet.createRow(rownum);
+		List<Term> terms = atom.getTerms();
+		Cell currCell;
+		if (terms.isEmpty()) {
+			// 0-arity atom
+			currCell = atomRow.createCell(0);
+			currCell.setCellValue(atom.getPredicate().getName());
+			sheet.autoSizeColumn(0);
+		} else {
+			for (int i = 0; i < terms.size(); i++) {
+				currCell = atomRow.createCell(i);
+				currCell.setCellValue(terms.get(i).toString());
+				sheet.autoSizeColumn(i);
+			}
+		}
+	}
+
+	private CellStyle createHeaderStyle(Workbook workbook) {
+		CellStyle headerStyle = workbook.createCellStyle();
+		Font headerFont = workbook.createFont();
+		headerFont.setFontHeightInPoints((short) 11);
+		headerFont.setBold(true); // (short) 0x74c4f2
+		headerStyle.setFont(headerFont);
+		headerStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);
+		headerStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
+		return headerStyle;
+	}
+
+	private Sheet createSheetWithHeader(Workbook wb, CellStyle headerStyle, String sheetName, String... headerContent) {
+		Sheet retVal = wb.createSheet(sheetName);
+		Row headerRow = retVal.createRow(0);
+		Cell cell;
+		for (int i = 0; i < headerContent.length; i++) {
+			cell = headerRow.createCell(i);
+			cell.setCellStyle(headerStyle);
+			cell.setCellValue(headerContent[i]);
+		}
+		return retVal;
+	}
+
+}