Java开发SDK详解-＞SDK开发

大家好，又见面了，我是你们的朋友全栈君。

一、前言

• 前面已经将服务端开发好了（服务端开发），现在我们来开发SDK吧。

二、详情

2.1 创建项目

• 创建一个普通的maven项目 maven—-》jdk选择1.8—–》next
  
• 输入groupId和artifactId
• 输入项目名称，和项目存放位置
  

2.2 开发代码

先看看项目的整体结构

2.2.1 pom文件

依赖的jar包

<dependencies>
  <!--json相关-->
   <dependency>
       <groupId>com.alibaba</groupId>
       <artifactId>fastjson</artifactId>
       <version>1.2.32</version>
   </dependency>
   <!-- 添加slf4j日志api -->
   <dependency>
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-api</artifactId>
       <version>1.7.20</version>
   </dependency>
   <!-- 添加logback-classic依赖 -->
   <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-classic</artifactId>
       <version>1.2.3</version>
   </dependency>
   <!-- 添加logback-core依赖 -->
   <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-core</artifactId>
       <version>1.2.3</version>
   </dependency>
   <!--lombok支持-->
   <dependency>
       <groupId>org.projectlombok</groupId>
       <artifactId>lombok</artifactId>
       <version>1.16.16</version>
   </dependency>
   <!--工具类-->
   <dependency>
       <groupId>org.apache.commons</groupId>
       <artifactId>commons-lang3</artifactId>
       <version>3.4</version>
   </dependency>
</dependencies>

2.2.2 SysUserClient

用户查询的客户端，继承ClientAbstract 类

package com.lh.hope.client;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.lh.hope.common.ReturnCodeEnum;
import com.lh.hope.domain.SysUser;
import com.lh.hope.domain.SysUserDTO;
import com.lh.hope.domain.common.ApiRequest;
import com.lh.hope.domain.common.BaseResponse;
import com.lh.hope.domain.common.PageModel;
import lombok.extern.slf4j.Slf4j;

@Slf4j
public class SysUserClient extends ClientAbstract { 
   

    public static BaseResponse<PageModel<SysUser>> queryUserList(ApiRequest<SysUserDTO> request) { 
   
        try { 
   
            String str = post(request);
            return JSON.parseObject(str, new TypeReference<BaseResponse<PageModel<SysUser>>>() { 
   
            });
        } catch (Exception e) { 
   
            log.error("SysUserClient queryUserList is exception! request={}", request);
            return BaseResponse.error(ReturnCodeEnum.SYSTEM_ERROR);
        }
    }
}

2.2.3 ClientAbstract

提供了入参加密，返回解密的功能，http请求。这里也可以添加参数校验的功能，这里省略。

package com.lh.hope.client;

import com.alibaba.fastjson.JSON;
import com.lh.hope.common.HopeException;
import com.lh.hope.common.ReturnCodeEnum;
import com.lh.hope.domain.common.ApiRequest;
import com.lh.hope.domain.common.HopeRequest;
import com.lh.hope.domain.common.HopeResponse;
import com.lh.hope.utils.HttpUtil;
import com.lh.hope.utils.RsaUtil;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;

@Slf4j
class ClientAbstract { 
   

    static String post(ApiRequest request) { 
   
        HopeRequest hopeRequest = HopeRequest.builder()
                .appId(request.getAppId())
                .data(RsaUtil.encrypt(request.getPublicKey(), JSON.toJSONString(request.getData())))
                .build();
        String s = HttpUtil.doPost(request.getUrl(), JSON.toJSONString(hopeRequest));
        if (StringUtils.isBlank(s)) { 
   
            log.error("client post api result is null!");
            throw new HopeException(ReturnCodeEnum.API_ERROR);
        }
        HopeResponse hopeResponse = JSON.parseObject(s, HopeResponse.class);
        if (!hopeResponse.isSuccess()) { 
   
            log.error("client post api error! hopeResponse={}", hopeResponse);
            throw new HopeException(ReturnCodeEnum.API_ERROR.getCode(), hopeResponse.getMessage());
        }
        return RsaUtil.decrypt(request.getPublicKey(), hopeResponse.getData());
    }
}

2.2.4 HttpUtil

Http请求的工具类，这里简单写一个psot请求的方法。参数传递方法为application/json。

package com.lh.hope.utils;

import lombok.extern.slf4j.Slf4j;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;

@Slf4j
public class HttpUtil { 
   

    /** * Http post请求 * * @param httpUrl 连接 * @param param 参数 * @return */
    public static String doPost(String httpUrl, String param) { 
   
        log.info(" HttpUtil doPost begin! httpUrl={} param={}", httpUrl, param);
        StringBuilder result = new StringBuilder();
        //连接
        HttpURLConnection connection = null;
        OutputStream os = null;
        InputStream is = null;
        BufferedReader br = null;
        try { 
   
            //创建连接对象
            URL url = new URL(httpUrl);
            //创建连接
            connection = (HttpURLConnection) url.openConnection();
            //设置请求方法
            connection.setRequestMethod("POST");
            //设置连接超时时间
            connection.setConnectTimeout(15000);
            //设置读取超时时间
            connection.setReadTimeout(15000);
            //DoOutput设置是否向httpUrlConnection输出，DoInput设置是否从httpUrlConnection读入，此外发送post请求必须设置这两个
            //设置是否可读取
            connection.setDoOutput(true);
            connection.setDoInput(true);
            //设置通用的请求属性
            connection.setRequestProperty("Content-Type", "application/json;charset=utf-8");
            connection.setRequestProperty("connection", "Keep-Alive");
            //拼装参数
            if (null != param && !param.equals("")) { 
   
                //设置参数
                os = connection.getOutputStream();
                //拼装参数
                os.write(param.getBytes("UTF-8"));
            }
            //开启连接
            connection.connect();
            //读取响应
            if (connection.getResponseCode() == 200) { 
   
                is = connection.getInputStream();
                if (null != is) { 
   
                    br = new BufferedReader(new InputStreamReader(is, "UTF-8"));
                    String temp = null;
                    while (null != (temp = br.readLine())) { 
   
                        result.append(temp);
                        result.append("\r\n");
                    }
                }
            }

        } catch (Exception e) { 
   
            e.printStackTrace();
            log.error("HttpUtil doPost exception! httpUrl={} param={}", httpUrl, param, e);
        } finally { 
   
            //关闭连接
            if (br != null) { 
   
                try { 
   
                    br.close();
                } catch (IOException e) { 
   
                    e.printStackTrace();
                }
            }
            if (os != null) { 
   
                try { 
   
                    os.close();
                } catch (IOException e) { 
   
                    e.printStackTrace();
                }
            }
            if (is != null) { 
   
                try { 
   
                    is.close();
                } catch (IOException e) { 
   
                    e.printStackTrace();
                }
            }
            //关闭连接
            if (connection != null) { 
   
                connection.disconnect();
            }
        }
        log.info(" HttpUtil doPost end! result={}", result);
        return result.toString();
    }

}

2.2.5 RsaUtil

RSA加解密的工具类

package com.lh.hope.utils;

import com.sun.org.apache.xerces.internal.impl.dv.util.Base64;
import lombok.extern.slf4j.Slf4j;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import java.security.Key;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Arrays;

@Slf4j
public class RsaUtil { 
   


    /** * 算法加解密算法 */
    private static final String ALGORITHM = "RSA";

    /** * 最大加密字节数，超出最大字节数需要分组加密 */
    private static final Integer MAX_ENCRYPT_BLOCK = 117;

    private static final Integer MAX_DECRYPT_BLOCK = 128;

    /** * 请求报文公钥解密 * * @param publicKeyString 公钥 * @param text 报文 * @return 加密报文 */
    public static String encrypt(String publicKeyString, String text) { 
   
        try { 
   
            PublicKey publicKey = getPublicKey(publicKeyString);
            return encryptRSA(publicKey, text);
        } catch (Exception e) { 
   
            e.printStackTrace();
            log.error("RsaUtil encrypt exception! publicKeyString={} text={}", publicKeyString, text);
            return null;
        }
    }

    /** * 应答报文公钥解密 * * @param publicKeyString 公钥 * @param text 应答密文 * @return 解密报文 */
    public static String decrypt(String publicKeyString, String text) { 
   
        try { 
   
            PublicKey publicKey = getPublicKey(publicKeyString);
            return decryptRSA(publicKey, text);
        } catch (Exception e) { 
   
            e.printStackTrace();
            log.error("RsaUtil decrypt exception! publicKeyString={} text={}", publicKeyString, text);
            return null;
        }
    }

    /** * RSA 加密 * * @param key 密钥 * @param text 原文 * @return 密文 * @throws Exception 异常 */
    private static String encryptRSA(Key key, String text) throws Exception { 
   
        // 创建加密对象
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        // 对加密进行初始化 第一个参数是加密模式，第二个参数是你想用的公钥加密还是私钥加密
        cipher.init(Cipher.ENCRYPT_MODE, key);
        // 分段加密
        byte[] make = doCrypt(text.getBytes(), cipher, MAX_ENCRYPT_BLOCK);
        return Base64.encode(make);
    }

    /** * RSA 解密 * * @param key 密钥 * @param text 密文 * @return 明文 * @throws Exception 异常 */
    private static String decryptRSA(Key key, String text) throws Exception { 
   
        // 创建加解密对象
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        // 对解密进行初始化 第一个参数是加密模式，第二个参数是你想用的公钥解密还是私钥解密
        cipher.init(Cipher.DECRYPT_MODE, key);
        //分段解密
        byte[] make = doCrypt(Base64.decode(text), cipher, MAX_DECRYPT_BLOCK);
        return new String(make);
    }

    /** * 分段加解密 * * @param data 要加解密的内容数组 * @param cipher 加解密对象 * @param maxBlock 分段大小 * @return 结果 * @throws IllegalBlockSizeException 异常 * @throws BadPaddingException 异常 */
    private static byte[] doCrypt(byte[] data, Cipher cipher, Integer maxBlock) throws IllegalBlockSizeException, BadPaddingException { 
   
        int inputLength = data.length;
        // 标识
        int offSet = 0;
        byte[] resultBytes = { 
   };
        byte[] cache;
        while (inputLength - offSet > 0) { 
   
            if (inputLength - offSet > maxBlock) { 
   
                cache = cipher.doFinal(data, offSet, maxBlock);
                offSet += maxBlock;
            } else { 
   
                cache = cipher.doFinal(data, offSet, inputLength - offSet);
                offSet = inputLength;
            }
            resultBytes = Arrays.copyOf(resultBytes, resultBytes.length + cache.length);
            System.arraycopy(cache, 0, resultBytes, resultBytes.length - cache.length, cache.length);
        }
        return resultBytes;
    }

    /** * 获取私钥 * * @param privateKeyString 私钥路径 * @return 私钥 */
    private static PrivateKey getPrivateKey(String privateKeyString) throws Exception { 
   
        // 创建key的工厂
        KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
        // 创建私钥key的规则
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(Base64.decode(privateKeyString));
        // 返回私钥对象
        return keyFactory.generatePrivate(keySpec);
    }

    /** * 获取公钥 * * @param publicKeyString 公钥 * @return 公钥 * @throws Exception 异常 */
    private static PublicKey getPublicKey(String publicKeyString) throws Exception { 
   
        // 创建key的工厂
        KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
        // 创建公钥key的规则
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(Base64.decode(publicKeyString));
        // 返回公钥对象
        return keyFactory.generatePublic(keySpec);
    }
}

2.2.5 App

测试类

package com.lh.hope;

import com.alibaba.fastjson.JSON;
import com.lh.hope.client.SysUserClient;
import com.lh.hope.domain.SysUser;
import com.lh.hope.domain.SysUserDTO;
import com.lh.hope.domain.common.ApiRequest;
import com.lh.hope.domain.common.BaseResponse;
import com.lh.hope.domain.common.PageModel;

public class App { 
   

    /** * 公钥 */
    private static final String PUBLIC_KEY_STRING = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCllRJyNyA5/kOKpF+VV322IN7fownz5GMltjnWLHJPE+xdusVYHz/3C0ck27sv7mHP0TrJ7PLxUHyeUJ9PGOZ2fyrBRikKNE4ce1ihNgQxorIJ68G+70eHyOr65mQxRYa4lUOHMMPHgicN/2vGCjwL/ET8eQU0yIRAoOnO8avAuQIDAQAB";
    
    public static void main(String[] args) { 
   
        SysUserDTO dto = new SysUserDTO();
        dto.setStatus(0);
        ApiRequest<SysUserDTO> request = ApiRequest.<SysUserDTO>builder()
                .appId("000001")
                .url("http://localhost:8081/api/user/queryUserList")
                .publicKey(PUBLIC_KEY_STRING)
                .data(dto)
                .build();
        BaseResponse<PageModel<SysUser>> pageModelBaseResponse = SysUserClient.queryUserList(request);
        System.out.println(JSON.toJSONString(pageModelBaseResponse));
    }

}

2.2.6 HopeRequest

这个是接口的入参，这里简单演示，一个客户端唯一编号（用来获取对应的私钥），一个是加密的入参。

package com.lh.entity.api;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class HopeRequest { 
   
    /** * 客户端唯一编号 */
    private String appId;

    /** * 加密后业务相关的入参 */
    private String data;
}

2.2.6 HopeResponse

package com.lh.entity.api;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class HopeResponse { 
   

    /** * 是否成功 */
    private boolean success;

    /** * 返回信息 */
    private String message;

    /** * 业务相关的返回信息，私钥加密之后的 */
    private String data;

}

2.2.7 ApiRequest

这个类是创建入参是用的，有客户端唯一Id（appId）,请求的接口地址，公钥还有业务相关的入参。

package com.lh.hope.domain.common;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class ApiRequest<T> { 
   

    private String url;
    private String publicKey;
    private String appId;
    private T data;

}

2.3 打包

2.3.1 设置

File ——》 Project Structure ——》 Project Settings ——》 Artifacts ——》 右栏左上角+ ——》JAR ——》 From Modules with dependencies——》OK

直接确定无需指定主类

不用更改 点击apply

2.3.2 构建

Build ——》 Build Artifacts

• Build（第一次构建）
• Rebuild（重新构建，会先自定清理上次构建jar包）
• Clean（清理构建好的jar包）
  
  jar生成在out文件夹下
  

三、最后

现在一个简单的SDK已经开发打包好了，服务端之前也已经开发并启动了，现在就剩下最后一步客户端引用SDK测试了。

• 上一篇服务端开发
• 下一篇客户端测试