Idea remote debugger

Preface

idea long-range debugger The project can find some that cannot be reproduced locally , But in jar Some problems in the package or on-site environment . The author takes a practical problem in work as an example , By the way, write down how to use idea long-range debugger

jar In bag File Troubleshooting and resolution of file missing exceptions

In one job , I will springboot The project into jar package , And then there was File Not Find It's abnormal . My code is as follows

public String getFileContent(Resource resource){
    
	File file = resource.getFile();
	try(FileInputStream fis = new FileInputStream(file)){
    
		byte[] bytes = new bytes[fs.available()];
		fs.read(bytes);
		return new String(bytes);
	} catch(Exception e){
    
		...
	}
	return null;
}

• No problem in the local environment , But in jar The reasons for the problems in the package environment are as follows （ Refer to blog portal ）：
  • Because the local environment obtains the target file in the form of relative path , So there's no problem ;
  • But it was a success jar After package , because jar A package is a separate file, not a folder , Therefore, it is not possible to obtain by relative path or absolute path jar Files inside the package .

//  resolvent ： Read in stream mode 
public String getFileContent(Resource resource){
    
	StringBuilder sb = new StringBuilder();
	try(InputStreamReader isr = new InputStreamReader(resource.getInputStream(), StandardCharset.UTF-8)){
    
		BufferedReader br = new BufferedReader(isr);
		String line;
		while((line = br.readLine) != null){
    
			sb.append(line);
		}
		return sb.toString();
	} catch(Exception e){
    
		...
	}
	return null;
}

Remote debugging and troubleshooting

In the local development environment , I have never been able to repeat this problem . But it doesn't work jar Package to start , It will be reported that the file cannot be found . At this time, I want to debug remotely jar To troubleshoot problems

• First step ： To configure idea Remote debugging
  

• The second step
  Make sure idea Your network can ping Pass target debugger Of jar Packet network

• The third step
  start-up jar package

java -Xdebug -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=8999 -jar ./xxx.jar

then jar Package printing is shown in the following figure , It means that the monitoring is successful 8999 port , Ready to be debugged remotely

• Step four
  Select the just configured remote To start the
  
  Then the console prints out this sentence , And it has been running . It means that remote debugging has been successfully started .
  
  It should be noted that , long-range debugger Of jar Bag classes Follow the local code classes Agreement , Otherwise, you may not be able to debug due to inconsistent code .

• Add
  idea long-range debugger Actual combat video portal