JSON Patch java库之json-patch

秒速五厘米 2021-09-02 07:53 444阅读 0赞

### 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][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][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：**

上篇blog（[https://blog.csdn.net/liuxiao723846/article/details/108547659][https_blog.csdn.net_liuxiao723846_article_details_108547659]）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][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

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpdXhpYW83MjM4NDY_size_16_color_FFFFFF_t_70][]

综上来看，还是推荐使用zjsonpatch

[RFC 6902]: http://tools.ietf.org/html/rfc6902
[RFC 7386]: http://tools.ietf.org/html/rfc7386
[Jackson]: https://github.com/FasterXML/jackson-databind
[https_github.com_java-json-tools_json-patch]: https://github.com/java-json-tools/json-patch
[https_github.com_java-json-tools_json-patch_releases]: https://github.com/java-json-tools/json-patch/releases
[https_blog.csdn.net_liuxiao723846_article_details_108547659]: https://blog.csdn.net/liuxiao723846/article/details/108547659
[https_github.com_java-json-tools_json-patch_issues]: https://github.com/java-json-tools/json-patch/issues
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpdXhpYW83MjM4NDY_size_16_color_FFFFFF_t_70]: /images/20210511/f7894992484b4efea25ffe041f6b5c30.png