Warning output in eclipse, how to solve this the right way?

[maur smith]

I have encountered some warning output in eclipse and I want to understand from someone more senior than I how they would handle this; before I start yes I am aware that we can simply suppress these warnings with annotations or simply tell the compiler but that's not exactly wise in this scenario I either want address them appropriately or leave them there ( the warnings) I am posting cause I am not 100% confident on my decision and want to arrive at the right solution with confidence for my team as this is for a customer .


Heres what i'm using:

- Eclipse
- Apache Tomcat
- package io.jsonwebtoken

public Key resolveSigningKey( JwsHeader header, Claims claims){
return getKey(header, claims);
}

WARNING OUTPUT : Jws is a raw type, Refrences to a generic type Jswheader<T> should be parameterized



SECOND ISSUE:

public List<Extra> getExtras( Claims claims, int choice){

EntitiyManager em = factory.createEntitiyManager();
em.getAction().begin();
DBuser user = getUser(em,claims);
Query q = em.createQuery("select form DbResult t);
List<DbResult> dbResult = q.getResultsList();

WARNING OUTPUT: Type saftey: the expression of type List needs unchecked conversions to conform to List<DbResult>

[David Simkulette]

These are both errors invoving generics. The first one is telling you that you are using a raw type (no generics) where a generics type <SomeType> is expected. The second one is teling you that the method getListResult is returning a non-parameterized (non-genericized) List but it is being assigned to a List<DbResult> - type object.

The java tutorial on oracle's site has a good beginner's intro to generics that will get you past these issues.

It's not an eclipse thing.

[Rob Spoor]

The fix for the first issue is to simply fill in a generic type or wildcard in the method signature. For instance:

public Key resolveSigningKey( JwsHeader<?> header, Claims claims){

The second issue requires you to use a different method, one that takes a class. This returns a TypedQueury (which is a generic sub type of Query):

TypedQuery<DbResult> q = em.createQuery("select form DbResult t, DbResult.class);
List<DbResult> dbResult = q.getResultsList();