Java Spring Boot中高效搜索JSON字符串并返回匹配子集的方法

需求场景 #

我正在开发Java Spring Boot应用，有如下格式的JSON数据：

{"version": "1.0.2","students": ["John Smith", "John Green", "Martin King"],"teachers": ["John Lord", "Martin Evans", "Steve John", "Gordon Lee", "Leo Martin"],"authors" : ["Martin Fowler", "Erich Gamma"]}

需要实现：输入指定搜索字符串，仅保留各数组中匹配的条目（忽略大小写），最终返回结构一致的JSON。例如搜索"mart"时，返回结果：

{"version": "1.0.2","students": ["Martin King"],"teachers": ["Martin Evans", "Leo Martin"],"authors" : ["Martin Fowler"]}

高效实现方案 #

1. 定义对应JSON的实体类

用Lombok简化实体类编写（也可手动实现getter/setter）：

import lombok.Data;
import java.util.List;

@Data
public class DataContainer {
    private String version;
    private List<String> students;
    private List<String> teachers;
    private List<String> authors;
}

2. 编写过滤逻辑

利用Spring Boot默认集成的Jackson库完成JSON序列化/反序列化，同时实现数组模糊匹配过滤：

import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.stereotype.Component;
import java.util.List;
import java.util.stream.Collectors;

@Component
public class JsonFilterService {
    private final ObjectMapper objectMapper;

    // 注入Spring默认的ObjectMapper实例
    public JsonFilterService(ObjectMapper objectMapper) {
        this.objectMapper = objectMapper;
    }

    public String filterJson(String originalJson, String searchKeyword) throws Exception {
        // 1. 将JSON反序列化为实体类对象
        DataContainer container = objectMapper.readValue(originalJson, DataContainer.class);
        
        // 2. 对每个数组字段进行过滤（忽略大小写）
        String lowerKeyword = searchKeyword.toLowerCase();
        container.setStudents(filterList(container.getStudents(), lowerKeyword));
        container.setTeachers(filterList(container.getTeachers(), lowerKeyword));
        container.setAuthors(filterList(container.getAuthors(), lowerKeyword));
        
        // 3. 将过滤后的对象序列化为JSON字符串返回
        return objectMapper.writeValueAsString(container);
    }

    // 通用过滤方法：保留列表中包含指定关键字的元素（忽略大小写）
    private List<String> filterList(List<String> list, String lowerKeyword) {
        if (list == null || list.isEmpty()) {
            return list;
        }
        return list.stream()
                .filter(item -> item.toLowerCase().contains(lowerKeyword))
                .collect(Collectors.toList());
    }
}

3. 使用示例

在Controller中调用该服务：

import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class JsonFilterController {
    private final JsonFilterService filterService;

    public JsonFilterController(JsonFilterService filterService) {
        this.filterService = filterService;
    }

    @PostMapping("/filter-json")
    public String filterJson(@RequestBody String originalJson, @RequestParam String keyword) throws Exception {
        return filterService.filterJson(originalJson, keyword);
    }
}

方案优势 #

• 复用Spring Boot原生Jackson库，无需额外引入依赖，兼容性强
• 采用Stream API过滤，代码简洁高效
• 通用过滤方法可复用，后续新增数组字段只需添加对应setter调用即可

内容的提问来源于stack exchange，提问作者ambuli