java - 使用外部 jar 在 debian 10 命令行中运行 java 程序

Question

我在我的以下程序中使用 postgresql-42.2.23.jar。我已经在 intelij ide 的 windows 环境中测试了代码，它工作正常。但我想在 linux 机器（运行 debian 10）中运行它命令行。现在 postgresql-42.2.23.jar 文件和 java 类文件位于 Music 文件夹中。

当我使用 “chathu@giottestserver:~/Music$ javac -cp Music/postgresql-42.2.23.jar serverinsert.java” 命令编译程序时，它会编译并创建类文件。

但是当我使用 “chathu@giottestserver:~/Music$ java -cp .:Music/postgresql-42.2.23.jar:serverinsert”运行 它时，它会给出以下消息，在此处输入图像描述

我也尝试过使用以下命令。但没有输出。 " chathu@giottestserver:~/Music$ java -cp .:Music/postgresql-42.2.23.jar serverinsert"

谁能帮我解决这个问题？

import java.sql.*;
import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;

public class serverinsert {
    public static void main(String []V){
        Connection c = null;
        Statement stmt = null;
        try
        {
            //Connecting to the database in local machine

            Class.forName("org.postgresql.Driver");
            c = DriverManager
                    .getConnection("jdbc:postgresql://localhost/",
                            "postgres", "gflow123");
            System.out.println("Opened database successfully");

            //Creation of a table to insert data in the local machine

            stmt = c.createStatement();
            String sql = "CREATE TABLE jason " +
                    "(ID INT      NOT NULL," +
                    " sendata json NOT NULL)";
            stmt.executeUpdate(sql); //updates the table
            System.out.println("Table created successfully");

            //Opening connection for DLC client

            ServerSocket ss = new ServerSocket(4000);
            Socket s = ss.accept();
            StringBuilder sb = new StringBuilder();
            BufferedReader br = new BufferedReader(new InputStreamReader(s.getInputStream()));
            String line;

            // DataOutputStream Dout = new DataOutputStream(s.getOutputStream());
            // BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            //String MsgIn="",MsgOut="";

            // inserting the DLC Data into a string variable called content
            String content="";
            while((line = br.readLine()) != null){
                sb.append(line).append(System.lineSeparator());
                content = sb.toString();

            }


            //Removing the http header content from the DLC Data

            String jsn=content.substring(content.indexOf("{"));

            //DLC received data processing
            System.out.println(jsn);
            String jsonreplacd=jsn.replace("[{\"name","\"name");
            System.out.println(jsonreplacd);
            String jsonreplacd1=jsonreplacd.replace("\"name","[\"INSERT INTO jason (ID,sendata) \" + \"VALUES ('1','')");
            System.out.println(jsonreplacd1);
            String jsonreplacd2=jsonreplacd1.replace("')\":\"press\",\"datatype\":\"float\",\"content\":","");
            System.out.println(jsonreplacd2);
            String jsn2=jsonreplacd2.substring(jsonreplacd2.indexOf("["));
            System.out.println(jsn2);
            String jsn3=jsn2.replace("[{","{");
            System.out.println(jsn3);
            String jsn4=jsn3.replace("\"t\"","\\\"t\\\"");
            System.out.println(jsn4);
            String jsn5=jsn4.replace("\"v\"","\\\"v\\\"");
            System.out.println(jsn5);
            String jsn6=jsn5.replace(":",":\\\"");
            System.out.println(jsn6);
            String jsn7=jsn6.replace(",\\","\\\",\\");
            System.out.println(jsn7);
            String jsn8=jsn7.replace("},","\\\"},");
            System.out.println(jsn8);
            String jsn9=jsn8.replace("}]}]}}","\\\"}')\"");
            System.out.println(jsn9);
            String jsn10=jsn9.replace("[","");
            System.out.println(jsn10);
            String jsn11=jsn10.replace("},{","}')\",\"INSERT INTO jason (ID,sendata) \" + \"VALUES ('1','{");
            System.out.println(jsn11);
            String jsn12=jsn11.replace("\",\"","\"@\"");
            System.out.println(jsn12);
           // String jsn3=jsn2.replace("\"","\\\"");
           //
           //
          //  String jsn6=jsn5.replace(",","\\\",");
          //  String jsn7=jsn6.
          //
           // String jsn9=jsn8.replace("}\\\"","}");

           // System.out.println(jsn9);

            // Creation of string array type to execute sql command

            //String[] strArray = new String[] {jsn11};
            //System.out.println(strArray[0]);

//String hi="hi";
            //String[] data = {"INSERT INTO jason (ID,sendata) " + "VALUES ('1','{\"t\":\"2104492460\",\"v\":\"-0.000769\"}')"};
            String[] data = jsn12.split("@");
            for(int i=0;i<5;i++) {
                //stmt.executeUpdate(data[i]);
                System.out.println(data[i]);
         }





            s.close();
        }

        catch(Exception e){

        }

    }
}

标签： javalinuxpostgresqlcommand-linejar

Answer 1

You are trying to run application with postgresql-42.2.23.jar dependency.

• "javac -cp Music/postgresql-42.2.23.jar serverinsert.java" - works, as syntax is correct
• "java -cp .:Music/postgresql-42.2.23.jar:serverinsert" - does not work, because serverinsert is not a .jar file (see also this)
• "java -cp .:Music/postgresql-42.2.23.jar serverinsert" - normally it shall work, but you did not post your "serverinsert" code. Instead we have "writedbtst", which I believe is your entry point (method main) and you shall run it instead of "serverinsert". You could save it as "serverinsert.java" if it was not public.

To sum up, If it works in your IDE, try running it on the same platform using command line and replacing main class accordingly. And please follow java class naming conventtion.