Bindings for lou_registerLogCallback and lou_setLogLevel

pom.xml

@@ -6,7 +6,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>org.liblouis</groupId>
   <artifactId>liblouis-java</artifactId>
-  <version>1.2.0</version>
+  <version>1.2.1-SNAPSHOT</version>
   <packaging>bundle</packaging>
   <name>liblouis-java</name>
   <description>JNA based Java bindings to liblouis, an open-source braille translator and back-translator.</description>
@@ -43,7 +43,7 @@
     <dependency>
       <groupId>org.liblouis</groupId>
       <artifactId>louis</artifactId>
-      <version>2.5.4</version>
+      <version>2.6.0-SNAPSHOT</version>
       <type>nar</type>
       <scope>test</scope>
     </dependency>

src/main/java/org/liblouis/Logger.java

@@ -0,0 +1,19 @@
+package org.liblouis;
+
+import com.sun.jna.Callback;
+
+public interface Logger extends Callback {
+
+	public static abstract class Level {
+		public static final int ALL = -2147483648;
+		public static final int DEBUG = 10000;
+		public static final int INFO = 20000;
+		public static final int WARN = 30000;
+		public static final int ERROR = 40000;
+		public static final int FATAL = 50000;
+		public static final int OFF = 2147483647;
+	}
+
+	public void invoke(int level, String message);
+
+}

src/main/java/org/liblouis/Louis.java

@@ -52,6 +52,10 @@ public int lou_translatePrehyphenated(String tableList, WideString inbuf, IntByR
 
 		public void lou_registerTableResolver(TableResolver resolver);
 
+		public void lou_registerLogCallback(Logger logger);
+
+		public void lou_setLogLevel(int level);
+
 	}
 
 	public static class TypeMapper extends DefaultTypeMapper {

src/test/java/org/liblouis/LoggerTest.java

@@ -0,0 +1,84 @@
+package org.liblouis;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FilenameFilter;
+import java.io.PrintStream;
+import java.util.Collection;
+
+import static org.apache.commons.io.filefilter.FileFilterUtils.asFileFilter;
+import static org.apache.commons.io.filefilter.FileFilterUtils.trueFileFilter;
+import org.apache.commons.io.FileUtils;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+import static org.liblouis.Logger.Level.DEBUG;
+import static org.liblouis.Logger.Level.INFO;
+import static org.liblouis.Logger.Level.WARN;
+import static org.liblouis.Logger.Level.ERROR;
+import static org.liblouis.Logger.Level.FATAL;
+
+public class LoggerTest {
+
+	@Test
+	public void testLogger() {
+		logger.reset();
+		try { new Translator("unexisting_file"); }
+		catch (CompilationException e) {}
+		assertEquals("[ERROR] Cannot resolve table 'unexisting_file'" + "\n" +
+		             "[ERROR] 1 errors found."                        + "\n" +
+		             "[ERROR] unexisting_file could not be found"     + "\n",
+		             logger.toString());
+		logger.reset();
+		Louis.getLibrary().lou_setLogLevel(FATAL);
+		try { new Translator("unexisting_file"); }
+		catch (CompilationException e) {}
+		assertEquals("", logger.toString());
+	}
+
+	private ByteArrayLogger logger;
+
+	@Before
+	@SuppressWarnings("unchecked")
+	public void initialize() {
+		final File testRootDir = new File(this.getClass().getResource("/").getPath());
+		Louis.setLibraryPath(((Collection<File>)FileUtils.listFiles(
+				new File(testRootDir, "../dependency"),
+				asFileFilter(new FilenameFilter() {
+					public boolean accept(File dir, String fileName) {
+						return dir.getName().equals("shared") && fileName.startsWith("liblouis"); }}),
+				trueFileFilter())).iterator().next());
+		logger = new ByteArrayLogger() {
+			public String format(int level, String message) {
+				switch (level) {
+				case DEBUG: return "[DEBUG] " + message;
+				case INFO: return "[INFO] " + message;
+				case WARN: return "[WARN] " + message;
+				case ERROR: return "[ERROR] " + message;
+				case FATAL: return "[FATAL] " + message; }
+				return null;
+			}
+		};
+		Louis.getLibrary().lou_registerLogCallback(logger);
+	}
+
+	private abstract class ByteArrayLogger implements Logger {
+		private ByteArrayOutputStream stream = new ByteArrayOutputStream();
+		private PrintStream printStream = new PrintStream(stream);
+		public abstract String format(int level, String message);
+		public void invoke(int level, String message) {
+			String formattedMessage = format(level, message);
+			if (formattedMessage != null)
+				printStream.println(formattedMessage);
+		}
+		public void reset() {
+			stream.reset();
+		}
+		public String toString() {
+			return stream.toString();
+		}
+	}
+}

src/test/java/org/liblouis/TranslatorTest.java

@@ -19,7 +19,7 @@ public class TranslatorTest {
 	@Test
 	public void testVersion() {
 		assertEquals(
-			"2.5.4",
+			"2.6.0-SNAPSHOT",
 			Louis.getLibrary().lou_version());
 	}