JSON Patch java库之json-patch

介绍

json-patch是Java编写的​​RFC 6902​​​（JSON Patch）和​​RFC 7386​​​（JSON Merge Patch）的实现，其核心使用​​Jackson​​​（2.2.x）。github地址：​​https://github.com/java-json-tools/json-patch​​

功能描述：

• 支持全部的RFC 6902 operations，包括test；
• 带有operations分解的JSON diff（仅RFC 6902）。

示例

maven pom.xml：

<dependency>
    <groupId>com.github.java-json-tools</groupId>
    <artifactId>json-patch</artifactId>
    <version>yourVersionHere</version>
</dependency>

当前版本是1.13，也可以在github 上的release上找对应的版本：​​https://github.com/java-json-tools/json-patch/releases​​

1、获取json diff信息作为patch：

import com.fasterxml.jackson.databind.ObjectMapper;
import com.github.fge.jsonpatch.JsonPatch;
import com.github.fge.jsonpatch.diff.JsonDiff;

public class PatchTest3 {
    private static final ObjectMapper mapper = new ObjectMapper();

    private static String json1 = "{\"a\":0,\"b\":[1,2]}";
    private static String json2 = "{\"b\": [1,2,0]} ";

    public static void main(String[] args) throws IOException {
        
        //JsonPatch patch = JsonDiff.asJsonPatch(source, target);
        JsonPatch patch = JsonDiff.asJsonPatch(mapper.readTree(json1), mapper.readTree(json2));
        System.out.println(patch.toString()); 
    }
}

输出：[op: move; from: "/a"; path: "/b/-"]

2、应用patch：

public class PatchTest3 {
    private static final ObjectMapper mapper = new ObjectMapper();

    private static String json1 = "{\"a\":0,\"b\":[1,2]}";
    private static String json2 = "{\"b\": [1,2,0]} ";

    public static void main(String[] args) throws Exception {
        
        //JsonPatch patch = JsonDiff.asJsonPatch(source, target);
        JsonPatch patch = JsonDiff.asJsonPatch(mapper.readTree(json1), mapper.readTree(json2));
        //System.out.println(patch.toString()); 
        
        
        JsonNode apply = patch.apply(mapper.readTree(json1));
        System.out.println(apply.toPrettyString());
    }
}

输出：{"b":[1,2,0]}

3、json-patch和zjsonpatch库对比：

介绍了zjsonpatch库，对比二者的区别：

• 前者支持关闭move、copy operations，json-patch这个库不支持关闭；（见github的issue：​​https://github.com/java-json-tools/json-patch/issues​​）
• json-patch返回的diff信息直接就是jsonPatch对象，而不是JSONNode

综上来看，还是推荐使用zjsonpatch