Jest mapping with getSourceAsObjectList()

Question

I tried to map elastic data to list. since getSourceAsObjectList() method is deprecated, I made code like this.

class activityObj {
    private String name;
    private String oid;
    public String getName()
    {
        return name;
    }
    public void setName( String name)
    {
        this.name = name;
    }
    public String getOid()
    {
        return oid;
    }
    public void setOid( String oid)
    {
        this.oid = oid;
    }
}

List< Hit<activityObj, Void>> hits = result.getHits(activityObj.class);
List< activityObj> list = new ArrayList<activityObj>();

for (SearchResult.Hit<activityObj, Void> hit: hits) {
    activityObj objectSource = hit.source; // null point error
    list.add(objectSource);
    logger.info( "hits : " + objectSource.getName());
}

It doesn't work as I expect and looks messy ( it's using two list value to map result). Am I doing wrong?

Answer 1

Have you tried something like this:

List< activityObj> list = hits.stream().map(h -> h.source).collect(Collectors.toList());

Answer 2

Michael's answer helped me and is a nice way to do it. Here's what I came up with including all the parts I used to make the query and get the result.

In my case I wanted to get a list of user ids collected from the source of each document in the result.

class DocSource {
    private Integer userId;

    public Integer getUserId() {
        return userId;
    }
}

String query = "{\n"
        + "    \"_source\": [\n"
        + "        \"userId\"\n"
        + "    ],\n"
        + "    \"query\": {\n"
        + "           <some query config here>"
        + "        }\n"
        + "   }\n"
        + "}";

Search search = new Search.Builder(query)
    .addIndex("my-index")
    .build();

SearchResult result = jestClient.execute(search);
List<SearchResult.Hit<DocSource, Void>> hits = result.getHits(DocSource.class);

List<Integer> listOfIds = hits.stream()
    .map(h -> h.source.getUserId())
    .collect(Collectors.toList());