Fix error when saving empty t-shirt size

code/moya-database/src/main/java/fi/codecrew/moya/model/GenericEntity.java

@@ -21,6 +21,7 @@ package fi.codecrew.moya.model;
 import javax.json.Json;
 import javax.json.JsonObject;
 import javax.json.JsonObjectBuilder;
+import javax.json.JsonValue;
 import javax.persistence.Column;
 import javax.persistence.Id;
 import javax.persistence.MappedSuperclass;
@@ -66,10 +67,28 @@ public class GenericEntity extends EntityEquals implements ModelInterface, Entit
 	@Transient
 	public String getMetaStringValue(String key) {
 		try {
-			return getMeta().getString(key);
+			JsonObject m = getMeta();
+			if(m != null && m.containsKey(key)) {
+				return getMeta().getString(key);
+			}
 		} catch (NullPointerException e) {
 			// this is normal if key is not found etc.
-			return "";
+		}
+		return "";
+	}
+
+	@Transient
+	public void deleteMetaKey(String key){
+		final JsonObject m = getMeta();
+		if(m != null){
+			JsonObjectBuilder metaBuilder = Json.createObjectBuilder();
+			getMeta()
+				.entrySet()
+				.stream()
+				.filter(e->!e.getKey().equals(key))
+				.forEach(e -> metaBuilder.add(e.getKey(), e.getValue()));
+
+			setMeta(metaBuilder.build());
 		}
 	}
 
@@ -79,15 +98,10 @@ public class GenericEntity extends EntityEquals implements ModelInterface, Entit
 		JsonObjectBuilder metaBuilder = Json.createObjectBuilder();
 
 		if (getMeta() != null) {
-			for (String valKey : getMeta().keySet()) {
-				if (!valKey.equals(key)) {
-					metaBuilder.add(valKey, getMeta().get(valKey));
-				}
-			}
+			getMeta().entrySet().forEach(e -> metaBuilder.add(e.getKey(), e.getValue()));
 		}
 
 		metaBuilder.add(key, value);
-
 		setMeta(metaBuilder.build());
 	}
 

code/moya-database/src/main/java/fi/codecrew/moya/model/User.java

@@ -58,6 +58,7 @@ public class User extends GenericEntity implements IUser {
 
 	public static final String ANONYMOUS_LOGINNAME = "anonymous";
 	private static final long serialVersionUID = -1632200627103418206L;
+	private static final String SHIRT_SIZE_METAKEY = "shirtSize";
 
 	@Column(name = "created", nullable = false, updatable = false)
 	@Temporal(TemporalType.TIMESTAMP)
@@ -433,12 +434,16 @@ public class User extends GenericEntity implements IUser {
 	
 	@Transient
 	public String getShirtSize() {
-		return getMetaStringValue("shirtSize");
+		return getMetaStringValue(SHIRT_SIZE_METAKEY);
 	}
 	
 	@Transient
 	public void setShirtSize(String size) {
-		setMetaStringValue("shirtSize", size);
+		if(size == null || size.isEmpty()){
+			deleteMetaKey(SHIRT_SIZE_METAKEY);
+		}else {
+			setMetaStringValue(SHIRT_SIZE_METAKEY, size);
+		}
 	}
 
 	public String getLocale() {