Jackson jsonGenerator生成Elasticsearch查询

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.io.IOException;
import java.io.StringWriter;

public class ElasticsearchQueryGenerator {
    public static void main(String[] args) {
        try {
            // 创建JsonGenerator
            JsonFactory jsonFactory = new JsonFactory();
            StringWriter writer = new StringWriter();
            JsonGenerator jsonGenerator = jsonFactory.createGenerator(writer);

            // 开始构建查询
            jsonGenerator.writeStartObject(); // 开始查询对象
            jsonGenerator.writeObjectFieldStart("query"); // 开始query字段
            jsonGenerator.writeObjectFieldStart("match"); // 开始match字段
            jsonGenerator.writeStringField("title", "Elasticsearch"); // 添加match字段的内容
            jsonGenerator.writeEndObject(); // 结束match字段
            jsonGenerator.writeEndObject(); // 结束query字段
            jsonGenerator.writeEndObject(); // 结束查询对象

            // 关闭JsonGenerator
            jsonGenerator.close();

            // 输出生成的查询
            System.out.println(writer.toString());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}