java 调用 python 脚本

有时候在java项目里，需要执行Python脚本以下几种方式：

1、直接执行Python脚本代码 
引用 org.python包  创建一个 python解释器，貌似这种方式不可以导入第三方库，模块。。。

PythonInterpreter interpreter = new PythonInterpreter();  
interpreter.exec("days=('mod','Tue','Wed','Thu','Fri','Sat','Sun'); ");   ///执行python脚本12

2 、执行python .py文件
PythonInterpreter interpreter = new PythonInterpreter();  
InputStream filepy = new FileInputStream("D:\demo.py"); 
interpreter.execfile(filepy);  ///执行python py文件
filepy.close();1234

3、使用Runtime.getRuntime()执行脚本文件
    这种方式和.net下面调用cmd执行命令的方式类似。如果执行的python脚本有引用第三方包的，建议使用此种方式。使用上面两种方式会报错java ImportError: No module named arcpy。
  
Process proc = Runtime.getRuntime().exec("python  D:\demo.py");  
proc.waitFor();  

项目webservice RESTful 风格 采用 sprintboot + jetty 内置容器打包 jar 方式运行 （持久层整合 mybatis）

因为当前公司项目我要负责编写 webservice 部分代码，而我们后台是采用 python 做 AI model，所以，避免不了要java与python交互传递数据，此外客户要求直接返回数据

仓促博客记录代码如下

定义调用python service 接口

public interface JPythonService {
    String callPythonScript(String pyFile,String params)throws Exception;
}

接口实现类

import com.middleplugin.exception.CustomException;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.concurrent.ConcurrentHashMap;
import com.middleplugin.service.JPythonService;
import com.middleplugin.utils.DBUtil;
import org.springframework.stereotype.Service;
import org.apache.log4j.Logger;
@Service
public class JPythonServiceImpl implements JPythonService{
    private Logger logger = Logger.getLogger(JPythonServiceImpl.class);
    @Override
    public String callPythonScript(String pyFile,String params) throws IOException{
        Process process = null;
        try{
            String[] command = new String[]{"sh", "-c","/home2/xxx/anaconda/envs/py35/bin/python "+pyFile+" '"+params+"'"};
            process = Runtime.getRuntime().exec(command);
            for(String s:command){
                System.out.print(s);
            }
            for(int i=0;i<=3;i++) {
                System.out.println();
            }

        }
        catch(IOException e){
//            e.printStackTrace();

            logger.error(e);
            throw e;
        }
        StringBuffer stringBuffer = new StringBuffer();
        InputStream stdIns = process.getInputStream();
        InputStream stdErrorIns= process.getErrorStream();

        BufferedInputStream stdInput = new BufferedInputStream(stdIns);
        BufferedInputStream stdError = new BufferedInputStream(stdErrorIns);

        ConcurrentHashMap<String,String> concurrentHashMap = new ConcurrentHashMap<String,String>();

        new Thread(){//读取标准输入流
            @Override
            public void run() {
                int bytesRead = 0;
                byte[] buffer=new byte[1024];
                try {
                    while ((bytesRead = stdInput.read(buffer)) != -1) {
                        String chunk = new String(buffer,0,bytesRead);
                        stringBuffer.append(chunk);
                        concurrentHashMap.put("stdInput",chunk);
                        System.out.println("result: "+stringBuffer.toString());
                    }
                }
                catch(IOException ioe){
                    ioe.printStackTrace();
                }
                finally{
                    if(stdInput!=null){
                        try{stdInput.close();}
                        catch(IOException ioe){
                            ioe.printStackTrace();
                        }}
                }
            }
        }.start();

        new Thread(){//读取标准错误流
            @Override
            public void run() {
                int bytesRead = 0;
                byte[] buffer=new byte[1024];
                try {
                    while ((bytesRead = stdError.read(buffer)) != -1) {
                        String chunk = new String(buffer,0,bytesRead);
                        stringBuffer.append(chunk);
                        concurrentHashMap.put("stdError",chunk);
                        System.out.println("result: "+stringBuffer.toString());
                    }
                }
                catch(IOException ioe){
                    ioe.printStackTrace();
                }
            }
        }.start();

        try {
            process.waitFor();
            process.destroy();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        if (concurrentHashMap.get("stdError")!=null){
            throw new CustomException("python 脚本有问题!");
//            DBUtil.insert_log();
        }
        return concurrentHashMap.get("stdInput");
    }
}

controller 层调用

@Autowired
    private JPythonService jPythonService;

@RequestMapping("/mtb/pyml")
    public JSONObject mtbML(@RequestBody JSONObject params){
        TriggerTaskServiceForMTBImpl  triggerTaskServiceForMTB = new TriggerTaskServiceForMTBImpl();
        JSONObject retJson = new JSONObject();
        String errorMessage = "success";
        Integer state = 200;
        String result = null;
        String treatmentRankingPyFile = config.getString("treatmentranking.file");
        try{ result = jPythonService.callPythonScript(treatmentRankingPyFile,params.toString());
        }
        catch(Exception e){
            errorMessage = e+" failed";
            state = 500;
            System.out.println("running ml script failed!");
        }
        retJson.put("errorMessage",errorMessage);
        retJson.put("state",state);
        retJson.put("result",result);
        return retJson;
    }