Java : ProcessHandle.Info with Examples

ProcessHandle.Info (Java SE 19 & JDK 19) API Examples.
You will find code examples on most ProcessHandle.Info methods.

Summary

Information snapshot about the process. The attributes of a process vary by operating system and are not available in all implementations. Information about processes is limited by the operating system privileges of the process making the request.

Class diagram

Please see also : Process, ProcessHandle

public class Main {
    public static void main(String[] args) {
        final var handle = ProcessHandle.current();
        final var info = handle.info();
        System.out.println("user = " + info.user());
        System.out.println("total cpu time = " + info.totalCpuDuration());
    }
}

// Result
// ↓
//> java Main
//user = Optional[MY-PC\xxxx]
//total cpu time = Optional[PT0.09375S]

Methods

Optional<String[]> arguments ()

Returns an array of Strings of the arguments of the process.

The following code runs on Linux.

public class Main {
    public static void main(String[] args) {
        System.out.println("args : " + Arrays.toString(args));

        final var handle = ProcessHandle.current();
        final var info = handle.info();

        info.command().ifPresent(command -> {
            System.out.println("command = " + command);
        });
        info.commandLine().ifPresent(commandLine -> {
            System.out.println("commandLine = " + commandLine);
        });
        info.arguments().ifPresent(arguments -> {
            System.out.println("arguments = " + Arrays.toString(arguments));
        });
    }
}

// Result
// ↓
//$ java Main aaa bbb
//args : [aaa, bbb]
//command = /home/xxxx/openjdk/jdk-19.0.2/bin/java
//commandLine = /home/xxxx/openjdk/jdk-19.0.2/bin/java Main aaa bbb
//arguments = [Main, aaa, bbb]

Optional<String> command ()

Returns the executable pathname of the process.

Please see arguments().

Optional<String> commandLine ()

Returns the command line of the process.

Please see arguments().

Optional<Instant> startInstant ()

Returns the start time of the process.

public class Main {
    public static void main(String[] args) {
        System.out.println("current time : " + Instant.now());

        // Uses about 15 seconds of CPU time.
        final var start = System.nanoTime();
        while (true) {
            if (System.nanoTime() - start >= 1000000000L * 15) {
                break;
            }
        }

        final var handle = ProcessHandle.current();
        final var info = handle.info();

        info.startInstant().ifPresent(instant -> {
            System.out.println("start instant = " + instant);
        });
        info.totalCpuDuration().ifPresent(duration -> {
            System.out.println("total cpu time = " + duration);
        });
    }
}

// Result
// ↓
//> java Main
//current time : 2023-03-25T07:52:44.806974500Z
//start instant = 2023-03-25T07:52:44.727Z
//total cpu time = PT14.828125S

Optional<Duration> totalCpuDuration ()

Returns the total cputime accumulated of the process.

Please see startInstant().

Optional<String> user ()

Return the user of the process.

public class Main {
    public static void main(String[] args) {
        final var handle = ProcessHandle.current();
        final var info = handle.info();
        info.user().ifPresent(user -> {
            System.out.println("user = " + user);
        });
    }
}

// Result
// ↓
//> java Main
//user = MY-PC\xxxx

API Examples