ElasticSearch 5 Java API SearchRequestBuilder examples

Now I will try to create few examples with SearchRequestBuilder  after I created the index in the previous example :

Java ElasticSearch 5 examples with node index and mapping - running local.

A new dependency was added to maven pom to convert Java objects to JSON and JSON to Java Object.

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.6.3</version>
        </dependency>

Now Is time to add few documents to the index:

        ObjectMapper objectMapper = new ObjectMapper();
        ExampleDocument exampleDocument;
        exampleDocument = new ExampleDocument("first document","Not Me",10);
        client.prepareIndex(indexName,documentType,"1").setSource(objectMapper.writeValueAsString(exampleDocument)).get();
        exampleDocument = new ExampleDocument("A nice book","Unknown Again",20);
        client.prepareIndex(indexName,documentType,"2").setSource(objectMapper.writeValueAsString(exampleDocument)).get();
        exampleDocument = new ExampleDocument("Old dusty","Author Again",50);
        client.prepareIndex(indexName,documentType,"3").setSource(objectMapper.writeValueAsString(exampleDocument)).get();
        exampleDocument = new ExampleDocument("New Car","Car Lover",55);
        client.prepareIndex(indexName,documentType,"4").setSource(objectMapper.writeValueAsString(exampleDocument)).get();

Now we have documents in index and we can start searching for them.

First example is a QueryBuilders.matchAllQuery()

    private static void searchRequestBuilderMatchAllQuery(String indexName, Client client) throws IOException {
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.readerFor(ExampleDocument.class);
        SearchRequestBuilder builder = client.prepareSearch(indexName);
        builder.setQuery(QueryBuilders.matchAllQuery());
        builder.addSort("pages", SortOrder.DESC);
        SearchResponse response = builder.get();
        for (SearchHit searchHit : response.getHits()) {
            ExampleDocument document= objectMapper.readValue(searchHit.getSourceAsString(), ExampleDocument.class);
            System.out.println(document);
        }
    }

Because I added a sort by pages DESC , the output is :

ExampleDocument{title='New Car', author='Car Lover', pages=55}
ExampleDocument{title='Old dusty', author='Author Again', pages=50}
ExampleDocument{title='A nice book', author='Unknown Again', pages=20}
ExampleDocument{title='first document', author='Not Me', pages=10}

 Now we will create a simple BoolQuery:

    private static void searchRequestBuilderBoolQuery(String indexName, Client client) throws IOException {
        System.out.println("SearchRequestBuilderExample.searchRequestBuilderBoolQuery");
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.readerFor(ExampleDocument.class);
        SearchRequestBuilder builder = client.prepareSearch(indexName);
        builder.setQuery(
                boolQuery()
                        .must(termQuery("title","first"))
                        .mustNot(termQuery("title", "book"))
        );
        builder.addSort("pages", SortOrder.DESC);
        SearchResponse response = builder.get();
        for (SearchHit searchHit : response.getHits()) {
            ExampleDocument document= objectMapper.readValue(searchHit.getSourceAsString(), ExampleDocument.class);
            System.out.println(document);
        }
    }

The title must contain "first" and must not contain "book", the result is :

SearchRequestBuilderExample.searchRequestBuilderBoolQuery
ExampleDocument{title='first document', author='Not Me', pages=10}

To build a multi level BoolQuery like a tree we have to combine must/should .... with boolQuery

        SearchRequestBuilder builder = client.prepareSearch(indexName);
        builder.setQuery(
                boolQuery()
                        .must(termQuery("title", "first"))
                        .must(
                                boolQuery()
                                        .must(termQuery("title", "document"))
                                        .must(termQuery("pages", 10)))
        );
        builder.addSort("pages", SortOrder.DESC);
        SearchResponse response = builder.get();

The output will be the same.

Enjoy !

the code can be found on GitHub SearchRequestBuilder Example source code