java/project/util/JsonSerializer.java

package com.crawler.util;

import com.crawler.model.CrawlerData;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;

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

public class JsonSerializer {

    private static final ObjectMapper objectMapper;

    static {
        objectMapper = new ObjectMapper();
        objectMapper.enable(SerializationFeature.INDENT_OUTPUT);
    }

    private JsonSerializer() {}

    public static void serializeToFile(List<CrawlerData> dataList, String filePath) throws IOException {
        File file = new File(filePath);
        File parentDir = file.getParentFile();
        if (parentDir != null && !parentDir.exists()) {
            parentDir.mkdirs();
        }
        objectMapper.writeValue(file, dataList);
    }

    public static List<CrawlerData> deserializeFromFile(String filePath) throws IOException {
        File file = new File(filePath);
        if (!file.exists()) {
            throw new IOException("文件不存在: " + filePath);
        }
        return objectMapper.readValue(file, new TypeReference<List<CrawlerData>>() {});
    }

    public static String toJsonString(List<CrawlerData> dataList) throws IOException {
        return objectMapper.writeValueAsString(dataList);
    }

    public static String toJsonString(CrawlerData data) throws IOException {
        return objectMapper.writeValueAsString(data);
    }

    public static List<CrawlerData> fromJsonString(String jsonString) throws IOException {
        return objectMapper.readValue(jsonString, new TypeReference<List<CrawlerData>>() {});
    }

    public static CrawlerData fromJsonStringToSingle(String jsonString) throws IOException {
        return objectMapper.readValue(jsonString, CrawlerData.class);
    }
}