Add UUID field mapper.

Used for correct mapping between PostgreSQL uuid type and java.util.UUID

Author: Mikhail Akushsky

src/main/java/de/zalando/typemapper/core/fieldMapper/FieldMapperRegister.java

@@ -4,6 +4,7 @@
 
 import java.util.Date;
 import java.util.Map;
+import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
 
 import de.zalando.typemapper.core.ValueTransformer;
@@ -62,6 +63,9 @@ public class FieldMapperRegister {
 
         final FieldMapper hstoreMapper = new HStoreFieldMapper();
         FieldMapperRegister.register(Map.class, hstoreMapper);
+
+        final FieldMapper uuidMapper = new UUIDFieldMapper();
+        FieldMapperRegister.register(UUID.class, uuidMapper);
     }
 
     @SuppressWarnings("rawtypes")

src/main/java/de/zalando/typemapper/core/fieldMapper/UUIDFieldMapper.java

@@ -0,0 +1,28 @@
+package de.zalando.typemapper.core.fieldMapper;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.UUID;
+
+/**
+ * Created by akushsky on 27.08.2015.
+ */
+public class UUIDFieldMapper implements FieldMapper {
+
+    private static final Logger LOG = LoggerFactory.getLogger(UUIDFieldMapper.class);
+
+    @Override
+    public Object mapField(String string, Class<?> clazz) {
+        if (string == null) {
+            return null;
+        }
+
+        try {
+            return UUID.fromString(string);
+        } catch (IllegalArgumentException e) {
+            LOG.error("Could not convert {} to UUID.", string);
+            return null;
+        }
+    }
+}