Added JavaVersion parser test

Contributed by Vincent Privat, see #75

findbugs/src/junit/edu/umd/cs/findbugs/JavaVersionTest.java

@@ -0,0 +1,56 @@
+/*
+ * FindBugs - Find Bugs in Java programs
+ * Copyright (C) 2003-2008 University of Maryland
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+package edu.umd.cs.findbugs;
+
+import junit.framework.TestCase;
+
+public class JavaVersionTest extends TestCase {
+
+    private static void testJavaVersionString(String version, int maj, int min, String rest)
+            throws JavaVersionException {
+        JavaVersion jv = new JavaVersion(version);
+        assertEquals(maj, jv.getMajor());
+        assertEquals(min, jv.getMinor());
+        assertEquals(rest, jv.getRest());
+    }
+
+    /**
+     * Test method for {@link edu.umd.cs.findbugs.JavaVersion#JavaVersion(java.lang.String)}.
+     * @throws JavaVersionException if version string cannot be parsed
+     */
+    public void testJavaVersionString() throws JavaVersionException {
+        // Historical versions (up to Java 8)
+        testJavaVersionString("1.7", 1, 7, "");
+        testJavaVersionString("1.7.0", 1, 7, "0");
+        testJavaVersionString("1.7.0_80", 1, 7, "0_80");
+        testJavaVersionString("1.8.0_66", 1, 8, "0_66");
+        // New scheme for Java 9 and later (JEP 223)
+        // See http://openjdk.java.net/jeps/223
+        testJavaVersionString("9-ea",  9, 0, "-ea");
+        testJavaVersionString("9",     9, 0, "");
+        testJavaVersionString("9.1.2", 9, 1, "2");
+        testJavaVersionString("9.0.1", 9, 0, "1");
+        // Long versions
+        testJavaVersionString("1.7.0_65-b20", 1, 7, "0_65-b20");
+        testJavaVersionString("7.6.15+20", 7, 6, "15+20");
+        testJavaVersionString("1.9.0-ea-b19", 1, 9, "0-ea-b19");
+        testJavaVersionString("9-ea+19", 9, 0, "-ea+19");
+    }
+}