進階玩法：策略+責任鏈+組合實作合約簽章

2024-06-09碼農

來源：juejin.cn/post/7256307512244650040

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1 前置內容

2 簽章的處理流程

3 流程實作

計畫結構

計畫類圖

責任鏈+組合模式程式碼實作

策略+責任鏈+組合程式碼實作

1 前置內容

掌握策略模式

掌握責任鏈模式

掌握類繼承、介面的實作

掌握參數的傳遞與設定

GitHub地址

ps：【文章由來】公司計畫中所用的合約簽章處理流程，本人基於責任鏈上使用策略模式進行最佳化。

2 簽章的處理流程

合約文本初始化

合約文本生成

簽章擋板是否開啟

合約簽章發送mq

合約簽章流水更新

合約上傳檔伺服器

簽章渠道選擇

簽章渠道的實際呼叫

執行的流程如下：

圖片

整個結構類似於遞迴呼叫。每個節點中依賴上一個節點的輸入以及下一個節點的輸出，在中間過程可以實作每個節點的自訂操作，比較靈活。

3 流程實作

GitHub地址

https://github.com/xbhog/DesignPatternsStudy

計畫結構

DesignPatterns └── src └── main └── java └── com.xbhog.chainresponsibility ├── annotations │ └── ContractSign ├── channel │ ├── ContractSignChannelImpl.java │ └── ContractSignChannel ├── Config │ └── SignConfig ├── Enum │ └── ContractSignEnum ├── impl │ ├── ContractSignCompactInitImpl.java │ ├── ContractSignGenerateImpl.java │ ├── ContractSignMockImpl.java │ ├── ContractSignMqImpl.java │ ├── ContractSignSaveUploadImpl.java │ ├── ContractSignSerialImpl.java │ └── ContractSignTradeImpl.java ├── inter │ ├── Call │ ├── Chain │ ├── Interceptor │ └── Processor ├── pojo │ ├── ContractRequest.java │ └── ContractResponse.java ├── ContractCall ├── ContractChain └── ContractSignProcessor.java

計畫類圖

圖片

責任鏈+組合模式程式碼實作

工程結構

DesignPatterns └── src └── main └── java └── com.xbhog.chainresponsibility ├── channel │ ├── ContractSignChannelImpl.java │ └── ContractSignChannel ├── impl │ ├── ContractSignCompactInitImpl.java │ ├── ContractSignGenerateImpl.java │ ├── ContractSignMockImpl.java │ ├── ContractSignMqImpl.java │ ├── ContractSignSaveUploadImpl.java │ ├── ContractSignSerialImpl.java │ └── ContractSignTradeImpl.java ├── inter │ ├── Call │ ├── Chain │ ├── Interceptor │ └── Processor ├── pojo │ ├── ContractRequest.java │ └── ContractResponse.java ├── ContractCall ├── ContractChain └── ContractSignProcessor.java

責任鏈中的物件定義

//請求 @Data @NoArgsConstructor @AllArgsConstructor @Builder public class ContractRequest { private String name; private String age; private String status; } //響應 @Data @NoArgsConstructor @AllArgsConstructor @Builder public class ContractResponse { private String status; private String mas; }

定義流程中的請求及響應類，方便處理每個責任鏈的請求、返回資訊。

責任鏈處理流程

合約簽章方法的主流程呼叫介面(入口) ，該類中註入所有的節點實作類(如 contractCompactInitImpl )，透過編排實作責任鏈流程。

在初始化節點之前，進行節點的封裝以及數據請求的處理。例： contractCompactInitImpl -合約數據初始化節點

/** * @author xbhog * @describe: 合約數據請求、節點的例項化及方法執行 * @date 2023/7/11 */ public class ContractCall<T extends ContractRequest> implements Call<T, ContractResponse> { private final T originalRequest; private final List<Interceptor<T,ContractRequest>> interceptorList; public ContractCall(T originalRequest, List<Interceptor<T, ContractRequest>> interceptorList) { this.originalRequest = originalRequest; this.interceptorList = interceptorList; } @Override public T request() { return this.originalRequest; } @Override public ContractResponse exectue() { //例項化流程節點 ContractChain<T> chain = new ContractChain(0,this.originalRequest,this.interceptorList); return chain.proceed(this.originalRequest); } }

獲取節點中的請求參數，例項化當前責任鏈節點( contractCompactInitImpl )，在執行節點中的proceed方法來獲取當前節點的參數以及獲取節點的資訊。

/** * @author xbhog * @describe: 合約節點 * @date 2023/7/11 */ @Slf4j public class ContractChain<T extends ContractRequest> implements Chain<T, ContractResponse> { private final Integer index; private final T request; private final List<Interceptor<T,ContractResponse>> interceptors; public ContractChain(Integer index, T request, List<Interceptor<T, ContractResponse>> interceptors) { this.index = index; this.request = request; this.interceptors = interceptors; } @Override public T request() { return this.request; } @Override public ContractResponse proceed(T request) { //控制節點流程 if(this.index >= this.interceptors.size()){ throw new IllegalArgumentException("index越界"); } //下一個節點參數設定 Chain<T,ContractResponse> nextChain = new ContractChain(this.index + 1, request, this.interceptors); //獲取節點資訊 Interceptor<T, ContractResponse> interceptor = this.interceptors.get(this.index); class<? extends Interceptor> a class = interceptor.get class(); log.info("當前節點：{}",a class.getSimpleName()); ContractResponse response = interceptor.process(nextChain); if(Objects.isNull(response)){ throw new NullPointerException("intercetor"+interceptor+"return null"); } return response; } }

到此合約簽章的架構流程已經確定，後續只要填充Interceptor具體的實作類即可。在程式碼中 ContractResponse response = interceptor.process(nextChain); 來執行合約初始化節點的具體操作。

/** * @author xbhog * @describe: 合約文本初始化 * @date 2023/7/12 */ @Slf4j @Component public class ContractSignCompactInitImpl<T extends ContractRequest> implements Interceptor<T, ContractResponse> { public ContractSignCompactInitImpl() { } @Override public ContractResponse process(Chain<T,ContractResponse> chain) { log.info("=============執行合約文本初始化攔截器開始"); //獲取處理的請求參數 T request = chain.request(); request.setStatus("1"); log.info("=============執行合約文本初始化攔截器結束"); //進入下一個責任鏈節點 ContractResponse response = chain.proceed(request); if(Objects.isNull(response)){ log.error("返回值的為空"); response = ContractResponse.builder().status("fail").mas("處理失敗").build(); } //其他處理 return response; } }

測試驗證

@SpringBootTest class SPringBootTestApplicationTests { @Autowired @Qualifier("contractSignProcessor") private Processor<ContractRequest,ContractResponse> contractSignProcessor; @Test void contextLoads() { ContractRequest contractRequest = new ContractRequest(); contractRequest.setName("xbhog"); contractRequest.setAge("12"); ContractResponse process = contractSignProcessor.process(contractRequest); System.out.println(process); } }

在這裏只需要呼叫合約簽章入口的方法即可進入合約簽章的流程。

2023-07-16 13:25:13.063 INFO 26892 --- [ main] c.e.s.c.ContractSignProcessor : 簽章開始 2023-07-16 13:25:13.067 INFO 26892 --- [ main] c.e.s.chainresponsibility.ContractChain : 當前節點：ContractSignCompactInitImpl 2023-07-16 13:25:13.068 INFO 26892 --- [ main] c.e.s.c.i.ContractSignCompactInitImpl : =============執行合約文本初始化攔截器開始 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.i.ContractSignCompactInitImpl : =============執行合約文本初始化攔截器結束 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.chainresponsibility.ContractChain : 當前節點：ContractSignGenerateImpl 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignGenerateImpl : =============執行合約文本生成攔截器開始 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignGenerateImpl : =============執行合約文本生成攔截器結束 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.chainresponsibility.ContractChain : 當前節點：ContractSignMockImpl 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignMockImpl : =============執行簽章擋板攔截器開始 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignMockImpl : =============執行簽章擋板攔截器結束 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.chainresponsibility.ContractChain : 當前節點：ContractSignMqImpl 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignMqImpl : =============執行合約簽章完成發送mq攔截器開始 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.chainresponsibility.ContractChain : 當前節點：ContractSignSerialImpl 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignSerialImpl : =============執行合約簽章流水處理攔截器開始 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.chainresponsibility.ContractChain : 當前節點：ContractSignSaveUploadImpl 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignSaveUploadImpl : =============執行合約簽章完成上傳伺服器攔截器開始 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.chainresponsibility.ContractChain : 當前節點：ContractSignTradeImpl 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignTradeImpl : =============執行簽章渠道實際呼叫攔截器開始 2023-07-16 13:25:13.069 INFO 26892 --- [ main] c.e.s.c.channel.ContractSignChannelImpl : 簽章處理開始 2023-07-16 13:25:13.070 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignSaveUploadImpl : 開始上傳伺服器 2023-07-16 13:25:13.070 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignSaveUploadImpl : ............. 2023-07-16 13:25:13.070 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignSaveUploadImpl : 上傳伺服器完成 2023-07-16 13:25:13.070 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignSaveUploadImpl : =============執行合約簽章完成上傳伺服器攔截器結束 2023-07-16 13:25:13.070 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignSerialImpl : =============執行合約簽章流水處理攔截器結束 2023-07-16 13:25:13.070 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignMqImpl : 發送MQ給下遊處理數據 2023-07-16 13:25:13.070 INFO 26892 --- [ main] c.e.s.c.impl.ContractSignMqImpl : =============執行合約簽章完成發送mq攔截器結束 ContractResponse(status=success, mas=處理成功)

策略+責任鏈+組合程式碼實作

以下是完整的合約簽章入口實作類：

/** * @author xbhog * @describe: 責任鏈+組合實作合約簽章 * @date 2023/7/11 */ @Slf4j @Component public class ContractSignProcessor <T extends ContractRequest> implements Processor<T, ContractResponse> { @Resource(name = "contractSignCompactInitImpl") private Interceptor<T,ContractResponse> contractCompactInitImpl; @Resource(name = "contractSignGenerateImpl") private Interceptor<T,ContractResponse> contractGenerateImpl; @Resource(name = "contractSignMockImpl") private Interceptor<T,ContractResponse> contractSignMockImpl; @Resource(name = "contractSignMqImpl") private Interceptor<T,ContractResponse> contractSignMqImpl; @Resource(name = "contractSignSaveUploadImpl") private Interceptor<T,ContractResponse> contractSignSaveUploadImpl; @Resource(name = "contractSignSerialImpl") private Interceptor<T,ContractResponse> contractSignSerialImpl; @Resource(name = "contractSignTradeImpl") private Interceptor<T,ContractResponse> ContractSignTradeImpl; public ContractSignProcessor() { } @Override public ContractResponse process(T paramter) { //獲取所有的監聽器 List<Interceptor<T,ContractResponse>> interceptorList = new ArrayList<>(); interceptorList.add(contractCompactInitImpl); interceptorList.add(contractGenerateImpl); interceptorList.add(contractSignMockImpl); interceptorList.add(contractSignMqImpl); interceptorList.add(contractSignSerialImpl); interceptorList.add(contractSignSaveUploadImpl); interceptorList.add(ContractSignTradeImpl); //開始簽章 log.info("簽章開始"); return new ContractCall(paramter,interceptorList).exectue(); } }

可以看到，目前的合約簽章的處理流程需要的節點數已經7個了，後續如果新增節點或者減少節點都需要對該類進行手動的處理；比如：減少一個節點的流程。

刪除節點實作的註入

刪除list中的bean實作類

為方便後續的拓展(懶是社會進步的加速器，不是)，在責任鏈，組合的基礎上透過策略模式來修改bean的註入方式。完整的計畫結構和計畫類圖就是作者文章開始放的，可返回檢視。在第一部份的基礎上增加的功能點如下

新增簽章註解

新增簽章節點列舉

新增簽章配置類

簽章註解實作

package com.example.springboottest.chainresponsibility.annotations; import com.example.springboottest.chainresponsibility.Enum.ContractSignEnum; import java.lang.annotation.*; /** * @author xbhog * @describe: * @date 2023/7/15 */ @Target(ElementType.TYPE) @Retention(RetentionPolicy.RUNTIME) public @interface ContractSign { ContractSignEnum.SignChannel SIGN_CHANNEL(); }

設定註解修飾物件的範圍，主要是對bean的一個註入，所以型別選擇type,

TYPE : 用於描述類、介面(包括註解型別) 或enum聲明

設定註解的執行周期(有效範圍)，一般是執行時有效，

RUNTIME ：在執行時有效 (大部份註解的選擇)

設定該註解的數據型別，

ENUM ：列舉型別，方便統一處理

列舉實作

package com.xbhog.chainresponsibility.Enum; /** * @author xbhog * @describe: * @date 2023/7/15 */ public class ContractSignEnum { public enum SignChannel { SIGN_INIT(1, "合約文本初始化"), SIGN_GENERATE(2, "合約文本生成"), SIGN_MOCK(3, "簽章擋板"), SIGN_MQ(4, "合約簽章完成發送MQ"), SIGN_TABLE(5, "合約簽章表處理"), SIGN_UPLOAD(6, "合約簽章完成上傳伺服器"), SIGN_TRADE(7, "簽章渠道實際呼叫"); private Integer code; private String info; SignChannel(Integer code, String info) { this.code = code; this.info = info; } ...... } }

對合約簽章中的流程節點進行統一的配置。

簽章配置類

在計畫啟動的時候，透過註解工具類 AnnotationUtils 掃描所有被 ContractSign 註解修飾的類，將這些類透過Map進行儲存，方便後續的呼叫。

public class SignConfig { @Resource protected List<Interceptor> contractSignList; protected static final Map<Integer,Interceptor> CONTRACT_SIGN_MAP = new ConcurrentHashMap<>(); @PostConstruct public void init(){ contractSignList.forEach(interceptor -> { //尋找這個介面的實作類上有沒有ContractSign註解 ContractSign sign = AnnotationUtils.findAnnotation(interceptor.get class(), ContractSign. class); if(!Objects.isNull(sign)){ CONTRACT_SIGN_MAP.put(sign.SIGN_CHANNEL().getCode(),interceptor); } }); } }

到此，簡化了Bean的註入方式。

簽章註解使用

以合約文本初始化 ContractSignCompactInitImpl 來說。

/** * @author xbhog * @describe: 合約文本初始化 * @date 2023/7/12 */ @Slf4j @ContractSign(SIGN_CHANNEL = ContractSignEnum.SignChannel.SIGN_INIT) @Component public class ContractSignCompactInitImpl<T extends ContractRequest> implements Interceptor<T, ContractResponse> { public ContractSignCompactInitImpl() { } @Override public ContractResponse process(Chain<T,ContractResponse> chain) { log.info("=============執行合約文本初始化攔截器開始"); //獲取處理的請求參數 T request = chain.request(); request.setStatus("1"); log.info("=============執行合約文本初始化攔截器結束"); //進入下一個責任鏈節點 ContractResponse response = chain.proceed(request); if(Objects.isNull(response)){ log.error("返回值的為空"); response = ContractResponse.builder().status("fail").mas("處理失敗").build(); } //其他處理 return response; } }

在該實作類上繫結了列舉 @ContractSign(SIGN_CHANNEL = ContractSignEnum.SignChannel.SIGN_INIT) . 在合約簽章入口類( ContractSignProcessor )中的變更如下：

@Slf4j @Component public class ContractSignProcessor <T extends ContractRequest> extends SignConfig implements Processor<T, ContractResponse> { public ContractSignProcessor() { } @Override public ContractResponse process(T paramter) { //獲取所有的監聽器 List<Interceptor<T,ContractResponse>> interceptorList = new ArrayList<>(); //獲取排序後的結果，保證責任鏈的順序，hashmap中key如果是數位的話，透過hashcode編碼後是有序的 for(Integer key : CONTRACT_SIGN_MAP.keySet()){ interceptorList.add(CONTRACT_SIGN_MAP.get(key)); } //開始簽章 log.info("簽章開始"); return new ContractCall(paramter,interceptorList).exectue(); } }