Java代码对es多字段查询

以下是一个Java代码示例，用于在Elasticsearch中进行多字段查询：

import java.io.IOException;
import java.util.Arrays;
import java.util.List;

import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.elasticsearch.index.query.MultiMatchQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.transport.client.PreBuiltTransportClient;

public class MultiFieldQueryExample {

    public static void main(String[] args) {
        String indexName = "my_index";
        String typeName = "my_type";
        String clusterName = "my_cluster";
        String host = "localhost";
        int port = 9300;

        // Create a client
        TransportClient client = new PreBuiltTransportClient(org.elasticsearch.common.settings.Settings.EMPTY)
                .addTransportAddress(new InetSocketTransportAddress(new java.net.InetSocketAddress(host, port)));

        // Query for multiple fields
        List<String> fields = Arrays.asList("field1", "field2", "field3");
        MultiMatchQueryBuilder queryBuilder = QueryBuilders.multiMatchQuery("search term", fields.toArray(new String[fields.size()]));

        // Build the search request
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        searchSourceBuilder.query(queryBuilder);
        searchSourceBuilder.from(0);
        searchSourceBuilder.size(10);

        // Execute the search
        SearchResponse searchResponse = client.prepareSearch(indexName).setTypes(typeName).setSource(searchSourceBuilder).get();

        // Process the search results
        SearchHits hits = searchResponse.getHits();
        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

        // Close the client
        try {
            client.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

在上面的示例中，我们使用Elasticsearch的Java API来执行一个多字段查询。我们使用了`MultiMatchQueryBuilder`来创建查询，然后使用`SearchSourceBuilder`来构建搜索请求。最后，我们使用`TransportClient`来发送搜索请求，并处理结果。