JDK 11 jdk.jdi.jmod is the JMOD file for JDK 11 JDI (Java Debug Interface) tool.

JDK 11 JDI tool compiled class files are stored in \fyicenter\jdk-11.0.1\jmods\jdk.jdi.jmod.

JDK 11 JDI tool compiled class files are also linked and stored in the \fyicenter\jdk-11.0.1\lib\modules JImage file.

JDK 11 JDI tool source code files are stored in \fyicenter\jdk-11.0.1\lib\src.zip\jdk.jdi.

You can click and view the content of each source code file in the list below.

⏎ com/sun/tools/jdi/SocketConnection.java

/*
 * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
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 *
 *
 *
 *
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 *
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 *
 *
 */

package com.sun.tools.jdi;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;

import com.sun.jdi.connect.spi.ClosedConnectionException;
import com.sun.jdi.connect.spi.Connection;

/*
 * The Connection returned by attach and accept is one of these
 */
class SocketConnection extends Connection {
    private Socket socket;
    private boolean closed = false;
    private OutputStream socketOutput;
    private InputStream socketInput;
    private Object receiveLock = new Object();
    private Object sendLock = new Object();
    private Object closeLock = new Object();

    SocketConnection(Socket socket) throws IOException {
        this.socket = socket;
        socket.setTcpNoDelay(true);
        socketInput = socket.getInputStream();
        socketOutput = socket.getOutputStream();
    }

    public void close() throws IOException {
        synchronized (closeLock) {
           if (closed) {
                return;
           }
           socketOutput.close();
           socketInput.close();
           socket.close();
           closed = true;
        }
    }

    public boolean isOpen() {
        synchronized (closeLock) {
            return !closed;
        }
    }

    public byte[] readPacket() throws IOException {
        if (!isOpen()) {
            throw new ClosedConnectionException("connection is closed");
        }
        synchronized (receiveLock) {
            int b1,b2,b3,b4;

            // length
            try {
                b1 = socketInput.read();
                b2 = socketInput.read();
                b3 = socketInput.read();
                b4 = socketInput.read();
            } catch (IOException ioe) {
                if (!isOpen()) {
                    throw new ClosedConnectionException("connection is closed");
                } else {
                    throw ioe;
                }
            }

            // EOF
            if (b1<0) {
               return new byte[0];
            }

            if (b2<0 || b3<0 || b4<0) {
                throw new IOException("protocol error - premature EOF");
            }

            int len = ((b1 << 24) | (b2 << 16) | (b3 << 8) | (b4 << 0));

            if (len < 0) {
                throw new IOException("protocol error - invalid length");
            }

            byte b[] = new byte[len];
            b[0] = (byte)b1;
            b[1] = (byte)b2;
            b[2] = (byte)b3;
            b[3] = (byte)b4;

            int off = 4;
            len -= off;

            while (len > 0) {
                int count;
                try {
                    count = socketInput.read(b, off, len);
                } catch (IOException ioe) {
                    if (!isOpen()) {
                        throw new ClosedConnectionException("connection is closed");
                    } else {
                        throw ioe;
                    }
                }
                if (count < 0) {
                    throw new IOException("protocol error - premature EOF");
                }
                len -= count;
                off += count;
            }

            return b;
        }
    }

    public void writePacket(byte b[]) throws IOException {
        if (!isOpen()) {
            throw new ClosedConnectionException("connection is closed");
        }

        /*
         * Check the packet size
         */
        if (b.length < 11) {
            throw new IllegalArgumentException("packet is insufficient size");
        }
        int b0 = b[0] & 0xff;
        int b1 = b[1] & 0xff;
        int b2 = b[2] & 0xff;
        int b3 = b[3] & 0xff;
        int len = ((b0 << 24) | (b1 << 16) | (b2 << 8) | (b3 << 0));
        if (len < 11) {
            throw new IllegalArgumentException("packet is insufficient size");
        }

        /*
         * Check that the byte array contains the complete packet
         */
        if (len > b.length) {
            throw new IllegalArgumentException("length mis-match");
        }

        synchronized (sendLock) {
            try {
                /*
                 * Send the packet (ignoring any bytes that follow
                 * the packet in the byte array).
                 */
                socketOutput.write(b, 0, len);
            } catch (IOException ioe) {
                if (!isOpen()) {
                    throw new ClosedConnectionException("connection is closed");
                } else {
                    throw ioe;
                }
            }
        }
    }
}

⏎ com/sun/tools/jdi/SocketConnection.java

Or download all of them as a single archive file:

File name: jdk.jdi-11.0.1-src.zip
File size: 464844 bytes
Release date: 2018-11-04
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