src/java.base/share/classes/jdk/internal/event/SocketReadEvent.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package jdk.internal.event;


import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.net.UnixDomainSocketAddress;

/**
 * A JFR event for socket read operations.  This event is mirrored in
 * {@code jdk.jfr.events.SocketReadEvent } where the metadata for the event is
 * provided with annotations.  Some of the methods are replaced by generated
 * methods when jfr is enabled.  Note that the order of the arguments of the
 * {@link #commit(long, long, String, String, int, long, long, boolean)} method
 * must be the same as the order of the fields.
 */
public class SocketReadEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String host;
    public String address;
    public int port;
    public long timeout;
    public long bytesRead;
    public boolean endOfStream;

    /**
     * Actually commit a socket read event.  The implementation
     * of this method is generated automatically if jfr is enabled.
     * The order of the fields must be the same as the parameters in this method.
     * {@code commit(..., String, String, int, long, long, boolean)}
     *
     * @param start     timestamp of the start of the operation
     * @param duration  time in nanoseconds to complete the operation
     * @param host      remote host of the transfer
     * @param address   remote address of the transfer
     * @param port      remote port of the transfer
     * @param timeout   timeout setting for the read
     * @param bytes     number of bytes that were transferred
     * @param endOfStream  has the end of the stream been reached
     */
    public static void commit(long start, long duration, String host, String address, int port, long timeout, long bytes, boolean endOfStream) {
        // Generated by JFR
    }

    /**
     * Determine if an event should be emitted.  The duration of the operation
     * must exceed some threshold in order to commit the event.  The implementation
     * of this method is generated automatically if jfr is enabled.
     *
     * @param duration  time in nanoseconds to complete the operation
     * @param end  timestamp at the end of the operation
     * @return  true if the event should be commited
     */
    public static boolean shouldThrottleCommit(long duration, long end) {
        // Generated by JFR
        return false;
    }

    /**
     * Determine if this kind of event is enabled.  The implementation
     * of this method is generated automatically if jfr is enabled.
     *
     * @return true if socket read events are enabled, false otherwise
     */
    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    /**
     * Fetch the current timestamp in nanoseconds.  This method is used
     * to determine the start and end of an operation.  The implementation
     * of this method is generated automatically if jfr is enabled.
     *
     * @return  the current timestamp value
     */
    public static long timestamp() {
        // Generated by JFR
        return 0L;
    }

    /**
     * Helper method to offer the data needed to potentially commit an event.
     * The duration of the operation is computed using the current
     * timestamp and the given start time.  If the duration is meets
     * or exceeds the configured value (determined by calling the generated method
     * {@link #shouldCommit(long)}), an event will be emitted by calling
     * {@link #emit(long, long, long, SocketAddress, long)}
     *
     * @param start  the start time
     * @param nbytes  how many bytes were transferred
     * @param remote  the address of the remote socket
     * @param timeout  maximum time to wait
     */
    public static void offer(long start, long nbytes, SocketAddress remote, long timeout) {
        long end = timestamp();
        long duration = end - start;
        if (shouldThrottleCommit(duration, end)) {
            emit(start, duration, nbytes, remote, timeout);
        }
    }

    /**
     * Helper method to perform a common task of getting event data ready and
     * then emitting the event by calling
     * {@link #commit(long, long, String, String, int, long, long, boolean)}.
     *
     * @param start  the start time
     * @param duration the duration
     * @param nbytes  how many bytes were transferred
     * @param remote  the address of the remote socket
     * @param timeout  maximum time to wait
     */
    public static void emit(long start, long duration, long nbytes, SocketAddress remote, long timeout) {
        boolean eof = nbytes < 0 ? true : false;
        nbytes = nbytes < 0 ? 0 : nbytes;
        if (remote instanceof InetSocketAddress isa) {
            commit(start, duration, isa.getHostString(), isa.getAddress().getHostAddress(), isa.getPort(), timeout, nbytes, eof);
        } else if (remote instanceof UnixDomainSocketAddress udsa) {
            String path = "[" + udsa.getPath().toString() + "]";
            commit(start, duration, "Unix domain socket", path, 0, timeout, nbytes, eof);
        }
    }

}