Java 运行 curl 命令在 Windows 和 ZEDC9F0A5A5D577978368E3736Z47 之间是不同的

Question

I use Spring Boot to write a api server, run on 192.168.24.102:7000,which accept restful api to create an app. Here is the problem I meet and even I finally solve it but I don't understand why?

When the curl command run on Linux, it is success, like this:

curl " https://192.168.24.102:7000/app/registerbyip " -X POST -H "Content-Type: application/json" -k -d "{\"ip\": \"192.168.24.102\", \"appType\": 5, \"appName\": \"efg\"}"

When the curl command run on Windows cmd it is also success, like this:

So the curl command is right, then I write it into Java code

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class TestDemo {
    public static String exeCurl(String[] cmds) {
        ProcessBuilder process = new ProcessBuilder(cmds);
        Process p;
        try {
            p = process.start();

            BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream()));
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line);
                sb.append(System.getProperty("line.separator"));
            }
            return sb.toString();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    public static void main(String[] args) {        
        String[] cmd = {"curl",
            "https://192.168.24.102:7000/app/registerbyip", "-k", "-H",
            "Content-Type: application/json;charset=UTF-8",
            "-X", "POST",
            "-d", "{\"ip\": \"192.168.24.102\", \"appType\": 5, \"appName\": \"efg\"}"};
        System.out.println(exeCurl(cmd));
    }
}

when this java code run on windows, the server will report exception like below:

{"timestamp":"2019-11-15T02:09:33.261+0000","status":400,"error":"Bad Request","message":"JSON parse error: Unexpected character ('i' (code 105)): was expecting double-quote to start field name; nested exception is com.fasterxml.jackson.core.JsonParseException: Unexpected character ('i' (code 105)): was expecting double-quote to start field name\n at [Source: (PushbackInputStream); line: 1, column: 3]","path":"/app/registerbyip"}

But I copy the java.class file to the linux, the run it will be success. Why? the same code run on Windows will fail but in linux will success.

Finally I fix the java curl code like this:

String[] cmd = {"curl",
    "https://192.168.24.102:7000/app/registerbyip", "-k", "-H",
    "Content-Type: application/json;charset=UTF-8",
    "-X", "POST",
    "-d", "{\"\"ip\"\": \"\"192.168.24.102\"\", \"\"appType\"\": 5, \"\"appName\"\": \"\"efg\"\"}"};

Then it will be success by add another \", but this java code will fail when run on Linux.

So here is my question? Why will it happen? Why the java code should add another \" sign? Please help, Thanks a lot.

Answer 1

Any specific reason why you're using curl for this? You can do exactly what you are doing there in pure Java with no curl and it will be easier and work great on Windows, Linux and whatever else. In Java 11 and later, use the new HttpClient . It's very simple. In earlier versions of Java, you can use the HttpURLConnection , but it's probably better to upgrade to 11 at this point.

Answer 2

It is because the client curl perform differently on different platform!

On windows, the param curl -d content,the string content show like:

{\"a\":\"123\"}  (in java "{\\\"a\\\" : \\\"123\\\"}")

or

{""a"":""123""}  (in java "{\"\"a\"\" : \"\"123\"\"}")

can be considered as {"a":"123"} by client curl.

On linux or mac, the -d content shown like: {"a":"123"} , the curl consider it as {"a":"123"} .