Add test for illegal memory access detection

Crashes were detected in production tests when Hyphenator is used with
the version 5.14 of JNA. See
daisy/pipeline-modules#102.

src/test/java/ch/sbs/jhyphen/HyphenatorTest.java

@@ -1,8 +1,11 @@
 package ch.sbs.jhyphen;
 
+import java.io.BufferedReader;
 import java.io.File;
+import java.io.FileReader;
 import java.io.FilenameFilter;
 import java.io.FileNotFoundException;
+import java.io.IOException;
 import java.util.Collection;
 
 import static org.apache.commons.io.filefilter.FileFilterUtils.asFileFilter;
@@ -14,9 +17,10 @@
 
 public class HyphenatorTest {
 
-	private static File tablesDir; {
+	private static File tablesDir, textFile; {
 		File testRootDir = new File(this.getClass().getResource("/").getPath());
 		tablesDir = new File(testRootDir, "tables");
+		textFile = new File(testRootDir, "test.txt");
 		Hyphen.setLibraryPath(((Collection<File>)FileUtils.listFiles(
 				new File(testRootDir, "../dependency"),
 				asFileFilter(new FilenameFilter() {
@@ -68,4 +72,32 @@ public void testNonStandardHyphenation() throws Exception {
 			hyphenator.close();
 		}
 	}
+
+	/**
+	 * Stability test over many runs on a simple text document.
+	 * (Introduced after crashes were detected when using JNA 5.14, that were
+	 * caused by early garbage collection of pointer.)
+	 *
+	 * @throws CompilationException
+	 * @throws FileNotFoundException
+	 * @throws IOException
+	 */
+	@Test
+	public void testManyRunsHyphenation() throws CompilationException, FileNotFoundException, IOException {
+		Hyphenator hyphenator = new Hyphenator(new File(tablesDir, "standard.dic"));
+		try{
+			for(int i = 0; i < 10; ++i){
+				BufferedReader testFileReader = new BufferedReader(new FileReader(textFile));
+				String line;
+				do {
+					line = testFileReader.readLine();
+					if(line != null){
+						hyphenator.hyphenate(line);
+					}
+				} while(line != null);
+			}
+		} finally {
+			hyphenator.close();
+		}
+	}
 }