MavenId fixes.

src/main/kotlin/com/beust/kobalt/maven/MavenId.kt

@@ -23,10 +23,18 @@ public class MavenId(val id: String) {
         }
         groupId = c[0]
         artifactId = c[1]
-        packaging = if (c.size == 4) c[2] else null
-        version = if (c.size == 4) c[3] else if (c.size == 3 && ! c[2].isBlank()) c[2] else null
+        if (! c[2].isEmpty()) {
+            if (isVersion(c[2])) {
+                version = c[2]
+            } else {
+                packaging = c[2]
+                version = c[3]
+            }
+        }
     }
 
+    private fun isVersion(s: String) : Boolean = Character.isDigit(s.get(0))
+
     val hasVersion = version != null
 
     val toId = MavenId.toId(groupId, artifactId, packaging, version)

src/test/kotlin/com/beust/kobalt/maven/MavenIdTest.kt

@@ -0,0 +1,33 @@
+package com.beust.kobalt.maven
+
+import org.testng.Assert
+import org.testng.annotations.DataProvider
+import org.testng.annotations.Test
+
+@Test
+class MavenIdTest {
+    @DataProvider
+    fun dp() : Array<Array<out Any?>> {
+        return arrayOf(
+            arrayOf("javax.inject:javax.inject:", "javax.inject", "javax.inject", null, null, null),
+            arrayOf("org.jetbrains.kotlin:kotlin-compiler-embeddable:1.0.0-beta-1038",
+                    "org.jetbrains.kotlin", "kotlin-compiler-embeddable", "1.0.0-beta-1038",
+                    null, null),
+            arrayOf("com.google.inject:guice:4.0:no_aop",
+                    "com.google.inject", "guice", "4.0", null, "no_aop"),
+            arrayOf("com.android.support:appcompat-v7:aar:22.2.1",
+                    "com.android.support", "appcompat-v7", "22.2.1", "aar", null)
+        )
+    }
+
+    @Test(dataProvider = "dp")
+    fun parseVersions(id: String, groupId: String, artifactId: String, version: String?,
+            packaging: String?, qualifier: String?) {
+        val mi = MavenId(id)
+        Assert.assertEquals(mi.groupId, groupId)
+        Assert.assertEquals(mi.artifactId, artifactId)
+        Assert.assertEquals(mi.version, version)
+        Assert.assertEquals(mi.packaging, packaging)
+//        Assert.assertEquals(mi.qualifier, qualifier)
+    }
+}