Simple Repl on Java

README.md

Start

java -cp out/production/SimpleRepl/ repl.SimpleRepl

Profiling using JMX

Start app:

java -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.port=1098 -cp ~/bin/SimpleRepl/ repl.SimpleRepl

Check port:

netstat -nlp | grep 1098

Then connect remotely.

See also http://hackers.lookout.com/2014/06/profiling-remote-jvms/

SimpleRepl.java

package repl;

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

/**
 * @author Alexander Shabanov
 */
public class SimpleRepl {
  public static void printHelp() {
    System.out.println("Available commands: printTime, help, exit, quit");
  }

  public static void main(String[] args) throws IOException {
    try (final BufferedReader r = new BufferedReader(new InputStreamReader(System.in))) {
      for (;;) {
        System.out.print("> ");
        final String line = r.readLine();
        System.out.println();
        switch (line) {
          case "help":
            printHelp();
            break;
          case "printTime":
            System.out.println("Time=" + new Date());
            break;
          case "quit":case "exit":
            return;

          default:
            System.out.println("Unknown command: " + line);
            printHelp();
        }
      }
    }
  }
}