1.首先介绍一下ES的查询类型，SearchType。
ES一共有四种查询类型：
QUERY_AND_FETCH：主节点将查询请求分发到所有的分片中，各个分片按照自己的查询规则即词频文档频率进行打分排序，然后将结果返回给主节点，主节点对所有数据进行汇总排序然后再返回给客户端，此种方式只需要和ES交互一次。
特点：a.存在数据量和排序问题，主节点会汇总所有分片返回的数据，这样数据量会比较大b.各个分片上的规则可能不一致
QUERY_THEN_FETCH:主节点将请求分发给所有分片，各个分片打分排序后将数据的id和分值返回给主节点，主节点收到后进行汇总排序，再根据排序后的id到对应的节点读取对应的数据再返回给客户端，此种方式需要和ES交互两次
特点：解决了数据量问题但是排序问题依然存在，是ES的默认查询方式
DFS_QUERY_AND_FETCH:和前面两种的区别在于将各个分片的规则统一起来进行打分
特点：解决了排序问题，但是仍然存在数据量问题
DFS_QUERY_THEN_FETCH:和前面两种的区别在于将各个分片的规则统一起来进行打分,将数据的id和分值返回给主节点，主节点收到后进行汇总排序，再根据排序后的id到对应的节点读取对应的数据再返回给客户端
特点：解决了排序和数据量问题但是效率是最差的2. 分页是会给服务器造成很大的压力。原因是会将分片的数据汇总后数据，如果有N个分片就会产生N倍的数量。
3.Java操作ES
依赖包：
<dependency>
<groupId>org.elasticsearch</groupId>
<artifactId>elasticsearch</artifactId>
<version>2.4.1</version>
</dependency>import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.ExecutionException;
import org.elasticsearch.action.bulk.BulkRequestBuilder;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.get.MultiGetItemResponse;
import org.elasticsearch.action.get.MultiGetResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.action.search.SearchType;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.action.update.UpdateResponse;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.text.Text;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentFactory;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.bucket.terms.Terms.Bucket;
import org.elasticsearch.search.aggregations.metrics.sum.Sum;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import com.alibaba.fastjson.JSON;
/**
* Hello world!
*
*/
public class App
{
private static TransportClient client;
static {
System.out.println("初始化链接。。。");
Map<String, String> map = new HashMap<>();
map.put("cluster.name", "my_home");
Settings.Builder settings = Settings.builder().put(map);
try {
client = TransportClient.builder().settings(settings).build()
.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), Integer.parseInt("9300")));
List<DiscoveryNode> nodes = client.connectedNodes();
for (DiscoveryNode node : nodes) {
System.out.println(node.getHostAddress());
}
} catch (NumberFormatException e) {
e.printStackTrace();
} catch (UnknownHostException e) {
e.printStackTrace();
}
}
public static void main(String[] args) throws Exception {
testPreference();
}
/**
* 功能描述: 增加索引
*
* @throws Exception void
* @version 1.0.6
* @author king
*/
public static void addIndex() throws Exception{
System.out.println("============分=====割=====线=============");
XContentBuilder source = createJson4();
// 存json入索引中
IndexResponse response = client.prepareIndex("twitter", "tweet", "4").setSource(source).get();
// 结果获取
String index = response.getIndex();
String type = response.getType();
String id = response.getId();
long version = response.getVersion();
boolean created = response.isCreated();
Map<String, Object> result = new HashMap<>();
result.put("index", index);
result.put("type", type);
result.put("id", id);
result.put("version", version);
result.put("created", created);
System.out.println(JSON.toJSONString(result));
}
/**
* 功能描述:删除索引
* void
* @version 1.0.6
* @author king
*/
public static void delIndex() {
System.out.println("======================删==除===分===割==线=================");
DeleteResponse deleteResponse = client.prepareDelete("twitter", "tweet", "1").get();
String index = deleteResponse.getIndex();
String type = deleteResponse.getType();
String id = deleteResponse.getId();
Long version = deleteResponse.getVersion();
Map<String, Object> result = new HashMap<>();
result.put("index", index);
result.put("type", type);
result.put("id", id);
result.put("version", version);
System.out.println(JSON.toJSONString(result));
}
/**
* 功能描述: 获取数据
* void
* @version 1.0.6
* @author king
*/
public static void getData() {
System.out.println("=================获==取==数==据==============");
GetResponse getResponse = client.prepareGet("tom", "cat", "2").execute().actionGet();
String id = getResponse.getId();
String resultStr = getResponse.getSourceAsString();
System.out.println("id" + id);
System.out.println("resultStr:" + resultStr);
}
/**
*
* */
public static void testGetThread() {
//设置线程安全
GetResponse getresponse = client.prepareGet("tom", "cat", "2").setOperationThreaded(false).get();
System.out.println(getresponse.getSourceAsString());
}
/**
* 功能描述: 更新ES数据
*
* @throws IOException
* @throws InterruptedException
* @throws ExecutionException void
* @version 1.0.6
* @author king
*/
public static void testUpdate() throws IOException, InterruptedException, ExecutionException {
UpdateRequest updateRequest = new UpdateRequest();
updateRequest.index("tom");
updateRequest.type("cat");
updateRequest.id("2");
updateRequest.doc(XContentFactory.jsonBuilder()
.startObject()
.field("phone", "17686886688")
.field("color", "blue")
.endObject());
UpdateResponse updateResponse = client.update(updateRequest).get();
String index = updateResponse.getIndex();
String type = updateResponse.getType();
String id = updateResponse.getId();
long version = updateResponse.getVersion();
Map<String, Object> result = new HashMap<>();
result.put("index", index);
result.put("type", type);
result.put("id", id);
result.put("version", version);
System.out.println(JSON.toJSONString(result));
}
/**
* 功能描述: 更新数据
*
* @throws IOException
* @throws InterruptedException
* @throws ExecutionException void
* @version 1.0.6
* @author yaoyaowang
*/
public static void testUpdate1() throws IOException, InterruptedException, ExecutionException {
UpdateRequest updateRequest = new UpdateRequest("tom", "cat", "2");
updateRequest.doc(XContentFactory.jsonBuilder()
.startObject()
.field("phone", "1366688866")
.endObject());
UpdateResponse updateResponse = client.update(updateRequest).get();
String index = updateResponse.getIndex();
String type = updateResponse.getType();
String id = updateResponse.getId();
long version = updateResponse.getVersion();
Map<String, Object> result = new HashMap<>();
result.put("index", index);
result.put("type", type);
result.put("id", id);
result.put("version", version);
System.out.println(JSON.toJSONString(result));
}
/**
* 功能描述: 新增数据，如果没有插入，如果有更新
*
* @throws IOException
* @throws InterruptedException
* @throws ExecutionException void
* @version 1.0.6
* @author yaoyaowang
*/
public static void testUpSert() throws IOException, InterruptedException, ExecutionException {
//查询该数据是否存在，如果不存在则插入
IndexRequest indexRequest = new IndexRequest("tom", "cat", "1");
indexRequest.source(XContentFactory.jsonBuilder()
.startObject()
.field("name", "staven")
.field("id", "2")
.field("age", "20")
.field("sex", "F")
.field("address", "America")
.field("phone", "110")
.field("color", "yello"));
//更新该数据，看该数据是否存在，如果不存在，则把上面的数据插入，如果存在则把数据更新（将"address", "America" 更新为 "address", "America"）
UpdateRequest updateRequest = new UpdateRequest("tom", "cat", "1");
updateRequest.doc(XContentFactory.jsonBuilder()
.startObject()
.field("address", "America")
.endObject());
updateRequest.upsert(indexRequest);
UpdateResponse updateResponse = client.update(updateRequest).get();
String index = updateResponse.getIndex();
String type = updateResponse.getType();
String id = updateResponse.getId();
long version = updateResponse.getVersion();
Map<String, Object> result = new HashMap<>();
result.put("index", index);
result.put("type", type);
result.put("id", id);
result.put("version", version);
System.out.println(JSON.toJSONString(result));
}
/**
* 功能描述: 增加索引
* void
* @version 1.0.6
* @author king
*/
public static void testMultiGet() {
MultiGetResponse multiGetResponse = client.prepareMultiGet()
.add("tom", "cat", "1")
.add("tom", "cat", "2")
.add("twitter", "tweet", "1")
.get();
for(MultiGetItemResponse itemReponse : multiGetResponse){
GetResponse getResponse = itemReponse.getResponse();
if(getResponse.isExists()){
String sourceAsString = getResponse.getSourceAsString();
System.out.println(sourceAsString);
}
}
}
/**
* 功能描述: 批处理
*
* @throws Exception void
* @version 1.0.6
* @author yaoyaowang
*/
public static void testBulk() throws Exception {
BulkRequestBuilder bulkBuilder = client.prepareBulk();
bulkBuilder.add(client.prepareIndex("tom", "cat", "3")
.setSource(XContentFactory.jsonBuilder()
.startObject()
.field("id", "2")
.field("name", "rose")
.field("age", "18")
.field("sex", "F")
.field("address", "tianjin")
.field("color", "black")
.field("phone", "120")
.endObject()));
bulkBuilder.add(client.prepareIndex("tom", "cat", "1")
.setSource(XContentFactory.jsonBuilder()
.startObject()
.field("address", "England")
.endObject()));
BulkResponse bulkResponse = bulkBuilder.get();
System.out.println(bulkResponse.getHeaders());
}
/**
* 功能描述: 统计索引下的数据
* void
* @version 1.0.6
* @author king
*/
public static void testCount(){
long num = client.prepareCount("twitter").get().getCount();
System.out.println(String.format("twitter的总数为：%d", num));
}
/**
* 功能描述: 查询
*
* void
* @version 1.0.6
* @author king
*/
public static void testSearch() {
Map<String, String> query = new HashMap<>();
query.put("name", "tom");
SearchResponse searchResponse = client.prepareSearch("twitter").setTypes("tweet")
//.setQuery(QueryBuilders.matchQuery("name", "tom").operator(Operator.AND)).setSearchType(SearchType.DEFAULT)
.setFrom(0).setSize(2).addSort("id", SortOrder.DESC)
.get();
SearchHits searchHits = searchResponse.getHits();
Long count = searchHits.getTotalHits();
System.out.println("总数：" + count);
SearchHit[] searchHitArr = searchHits.getHits();
for(SearchHit searchHit : searchHitArr){
System.out.println(searchHit.getSourceAsString());
}
}
/**
* 功能描述: 筛选
* void
* @version 1.0.6
* @author king
*/
public static void testFilter() {
SearchResponse searchResponse = client.prepareSearch("twitter").setTypes("tweet")
.setQuery(QueryBuilders.matchAllQuery())
.setPostFilter(QueryBuilders.rangeQuery("age").gte(17))
.setFrom(0).addSort("id", SortOrder.ASC)
.get();
SearchHits searchHits = searchResponse.getHits();
Long total = searchHits.getTotalHits();
System.out.println("年龄大于17的数据总数" + total);
SearchHit[] searchHitArr = searchHits.getHits();
for(SearchHit searchHit : searchHitArr){
System.out.println(searchHit.getSourceAsString());
}
}
/**
* 功能描述: 高亮
* void
* @version 1.0.6
* @author king
*/
public static void testHighLight() {
SearchResponse searchResponse = client.prepareSearch("twitter").setTypes("tweet")
.setQuery(QueryBuilders.matchQuery("name", "tom"))
.setSearchType(SearchType.QUERY_THEN_FETCH)
.addHighlightedField("name")
.setHighlighterPreTags("<font color='red'>")
.setHighlighterPostTags("</font>")
.get();
SearchHits searchHits = searchResponse.getHits();
long total = searchHits.getTotalHits();
System.out.println("索引twitter下的所有数据的总数：" + total);
SearchHit[] searchHitArr = searchHits.getHits();
for(SearchHit searchHit : searchHitArr){
Map<String, HighlightField> highlightFields = searchHit.getHighlightFields();
HighlightField highlightField = highlightFields.get("name");
if(null != highlightField){
Text[] fragments = highlightField.fragments();
System.out.println("这是个什么鬼呢？ ---> " + fragments[0]);
}
System.out.println(searchHit.sourceAsString());
}
}
/**
* 功能描述: 分组统计
* void
* @version 1.0.6
* @author king
*/
public static void testGroupBy() {
SearchResponse searchResponse = client.prepareSearch("twitter").setTypes("tweet")
.setQuery(QueryBuilders.matchAllQuery())
.setSearchType(SearchType.QUERY_THEN_FETCH)
.addAggregation(AggregationBuilders.terms("group_age").field("age").size(0))
.get();
Terms terms = searchResponse.getAggregations().get("group_age");
List<Bucket> buckets = terms.getBuckets();
for(Bucket bucket : buckets){
System.out.println(bucket.getKey() + ":" + bucket.getDocCount());
}
}
/**
* 功能描述: 聚合
* void
* @version 1.0.6
* @author king
*/
public static void testAggregationFunction() {
SearchResponse searchResponse = client.prepareSearch("twitter").setTypes("tweet")
.setQuery(QueryBuilders.matchAllQuery())
.setSearchType(SearchType.QUERY_THEN_FETCH)
.addAggregation(AggregationBuilders.terms("group_name").field("name")
.subAggregation(AggregationBuilders.sum("age_count").field("age")))
.get();
Terms terms = searchResponse.getAggregations().get("group_name");
List<Bucket> buckets = terms.getBuckets();
for(Bucket bucket : buckets){
Sum sum = bucket.getAggregations().get("age_count");
System.out.println("{" + bucket.getKey() + ":" + bucket.getDocCount() + ":" + sum.getValue() + "}");
}
}
/**
* 功能描述: 造数据
*
* @throws IOException void
* @version 1.0.6
* @author king
*/
public static void generateOtherIndexData() throws IOException {
for(int i = 1; i <= 60; i++){
XContentBuilder source = XContentFactory.jsonBuilder()
.startObject()
.field("id", i)
.field("name", createName())
.field("sex", (i < 30 ? "F" : "M"))
.field("age", createAge())
.field("address", "china")
.endObject();
client.prepareIndex("ycu", "computer", String.valueOf(i-1)).setSource(source).get();
}
}
/**
* 功能描述: 创建人名
*
* @return String
* @version 1.0.6
* @author king
*/
public static String createName(){
Random random = new Random();
String[] str = {"q","w","e","r","t","y","u","i","o","p","a","s","f","d","g","h","j","k","l","z","x","c","v","b","n","m"};
random.nextInt(23);
String name = new StringBuffer(str[random.nextInt(23)]).append(str[random.nextInt(23)])
.append(str[random.nextInt(23)]).toString();
return name;
}
/**
* 功能描述: 创建年龄
*
* @return int
* @version 1.0.6
* @author king
*/
public static int createAge(){
Random random = new Random();
String[] num = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"};
String ageStr = new StringBuffer(num[random.nextInt(10)]).append(num[random.nextInt(10)]).toString();
return Integer.parseInt(ageStr);
}
/**
* 功能描述: 指定分片区查询数据
* void
* @version 1.0.6
* @author king
*/
public static void testPreference(){
SearchResponse searchResponse = client.prepareSearch("ycu").setTypes("computer").setPreference("_shards:0,1")
.setQuery(QueryBuilders.matchAllQuery()).setExplain(true).setFrom(0).setSize(60).get();
SearchHits searchHits = searchResponse.getHits();
long total = searchHits.getTotalHits();
SearchHit[] searchHitArr = searchHits.getHits();
System.out.println("总数：" + total);
for(SearchHit searchHit : searchHitArr){
System.out.println(searchHit.getSourceAsString());
}
}
/**
* 使用es的帮助类
*/
public static XContentBuilder createJson4() throws Exception {
// 创建json对象, 其中一个创建json的方式
XContentBuilder source = XContentFactory.jsonBuilder()
.startObject()
.field("id", "5")
.field("name", "tom")
.field("sex", "F")
.field("age", 19)
.field("address", "china")
.endObject();
return source;
}
}
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