Support for parsing versions from maven pom.properties files

src/main/java/com/fasterxml/jackson/core/util/VersionUtil.java

@@ -1,6 +1,7 @@
 package com.fasterxml.jackson.core.util;
 
 import java.io.*;
+import java.util.Properties;
 import java.util.regex.Pattern;
 
 import com.fasterxml.jackson.core.Version;
@@ -97,6 +98,41 @@ public static Version versionFor(Class<?> cls)
         return (version == null) ? Version.unknownVersion() : version;
     }
 
+    /**
+     * Will attempt to load the maven version for the given groupId and
+     * artifactId.  Maven puts a pom.properties file in
+     * META-INF/maven/groupId/artifactId, containing the groupId,
+     * artifactId and version of the library.
+     *
+     * @param classLoader the ClassLoader to load the pom.properties file from
+     * @param groupId the groupId of the library
+     * @param artifactId the artifactId of the library
+     * @return The version
+     */
+    public static Version mavenVersionFor(ClassLoader classLoader, String groupId, String artifactId) {
+        InputStream pomPoperties = classLoader.getResourceAsStream("META-INF/maven/" + groupId.replaceAll("\\.", "/")
+                + "/" + artifactId + "/pom.properties");
+        if (pomPoperties != null) {
+            try {
+                Properties props = new Properties();
+                props.load(pomPoperties);
+                String versionStr = props.getProperty("version");
+                String pomPropertiesArtifactId = props.getProperty("artifactId");
+                String pomPropertiesGroupId = props.getProperty("groupId");
+                return parseVersion(versionStr, pomPropertiesGroupId, pomPropertiesArtifactId);
+            } catch (IOException e) {
+                // Ignore
+            } finally {
+                try {
+                    pomPoperties.close();
+                } catch (IOException e) {
+                    // Ignore
+                }
+            }
+        }
+        return Version.unknownVersion();
+    }
+
     /**
      * Use variant that takes three arguments instead
      * 

src/test/java/com/fasterxml/jackson/core/util/TestVersionUtil.java

@@ -1,7 +1,6 @@
 package com.fasterxml.jackson.core.util;
 
 import com.fasterxml.jackson.core.Version;
-import com.fasterxml.jackson.core.util.VersionUtil;
 
 public class TestVersionUtil extends com.fasterxml.jackson.test.BaseTest
 {
@@ -16,4 +15,9 @@ public void testVersionParsing()
     {
         assertEquals(new Version(1, 2, 15, "foo"), VersionUtil.parseVersion("1.2.15-foo"));
     }
+
+    public void testMavenVersionParsing() {
+        assertEquals(new Version(1, 2, 3, "SNAPSHOT", "foo.bar", "foo-bar"),
+                VersionUtil.mavenVersionFor(TestVersionUtil.class.getClassLoader(), "foo.bar", "foo-bar"));
+    }
 }

src/test/resources/META-INF/maven/foo/bar/foo-bar/pom.properties

@@ -0,0 +1,3 @@
+groupId=foo.bar
+artifactId=foo-bar
+version=1.2.3-SNAPSHOT