1.15.2 Get console command output

Spoiler: logger class

Code (Java):

import java.util.ArrayList;
import java.util.List;

import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.appender.AbstractAppender;
import org.apache.logging.log4j.core.layout.PatternLayout;

public class MessageLogger extends AbstractAppender {
    private boolean isLogging;
    private List<String> loggedData;

    @SuppressWarnings("deprecation")
    public MessageLogger() {
     
        super("YourPluginNameAppenderOrSomething", null, PatternLayout.newBuilder().withPattern("%m%n").build());

        isLogging = false;
        loggedData = new ArrayList<String>();
    }

    public void startLogging() {
        isLogging = true;
    }

    public void stopLogging() {
        isLogging = false;
    }

    public void clearData() {
        loggedData.clear();
    }

    public List<String> getData() {
        return new ArrayList<String>(loggedData);
    }

    public void log(String message) {
        if (isLogging) {
            loggedData.add(message);
        }
    }

    @Override
    public boolean isStarted() {
        return true;
    }

    @Override
    public void append(LogEvent event) {
        log(event.getMessage().getFormattedMessage());
    }
}

and then, on plugin load:

Code (Java):

MessageLogger cmdLogger = new MessageLogger();

Logger log = (Logger) LogManager.getRootLogger();
log.addAppender(cmdLogger);

 

you save somewhere the MessageLogger instance you made in your onEnable method, and when you want to execute a command you perform

Code (Text):

yourMessageLoggerInstance.startLogging();
//execute your command(s) here
yourMessageLoggerInstance.stopLogging();
List<String> result = yourMessageLoggerInstance.getData();
yourMessageLoggerInstance.clearData();