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How to use read method of sun.tools.attach.LinuxVirtualMachine class

Best Powermock code snippet using sun.tools.attach.LinuxVirtualMachine.read

Source:LinuxVirtualMachine.java

...39    // location is the same for all processes, otherwise the tools40    // will not be able to find all Hotspot processes.41    // Any changes to this needs to be synchronized with HotSpot.42    private static final String tmpdir = "/tmp";43    // Indicates if this machine uses the old LinuxThreads44    static boolean isLinuxThreads;45    // The patch to the socket file created by the target VM46    String path;47    /**48     * Attaches to the target VM49     */50    LinuxVirtualMachine(AttachProvider provider, String vmid)51        throws AttachNotSupportedException, IOException52    {53        super(provider, vmid);54        // This provider only understands pids55        int pid;56        try {57            pid = Integer.parseInt(vmid);58        } catch (NumberFormatException x) {59            throw new AttachNotSupportedException("Invalid process identifier");60        }61        // Find the socket file. If not found then we attempt to start the62        // attach mechanism in the target VM by sending it a QUIT signal.63        // Then we attempt to find the socket file again.64        path = findSocketFile(pid);65        if (path == null) {66            File f = createAttachFile(pid);67            try {68                // On LinuxThreads each thread is a process and we don't have the69                // pid of the VMThread which has SIGQUIT unblocked. To workaround70                // this we get the pid of the "manager thread" that is created71                // by the first call to pthread_create. This is parent of all72                // threads (except the initial thread).73                if (isLinuxThreads) {74                    int mpid;75                    try {76                        mpid = getLinuxThreadsManager(pid);77                    } catch (IOException x) {78                        throw new AttachNotSupportedException(x.getMessage());79                    }80                    assert(mpid >= 1);81                    sendQuitToChildrenOf(mpid);82                } else {83                    sendQuitTo(pid);84                }85                // give the target VM time to start the attach mechanism86                int i = 0;87                long delay = 200;88                int retries = (int)(attachTimeout() / delay);89                do {90                    try {91                        Thread.sleep(delay);92                    } catch (InterruptedException x) { }93                    path = findSocketFile(pid);94                    i++;95                } while (i <= retries && path == null);96                if (path == null) {97                    throw new AttachNotSupportedException(98                        "Unable to open socket file: target process not responding " +99                        "or HotSpot VM not loaded");100                }101            } finally {102                f.delete();103            }104        }105        // Check that the file owner/permission to avoid attaching to106        // bogus process107        checkPermissions(path);108        // Check that we can connect to the process109        // - this ensures we throw the permission denied error now rather than110        // later when we attempt to enqueue a command.111        int s = socket();112        try {113            connect(s, path);114        } finally {115            close(s);116        }117    }118    /**119     * Detach from the target VM120     */121    public void detach() throws IOException {122        synchronized (this) {123            if (this.path != null) {124                this.path = null;125            }126        }127    }128    // protocol version129    private final static String PROTOCOL_VERSION = "1";130    // known errors131    private final static int ATTACH_ERROR_BADVERSION = 101;132    /**133     * Execute the given command in the target VM.134     */135    InputStream execute(String cmd, Object ... args) throws AgentLoadException, IOException {136        assert args.length <= 3;                // includes null137        // did we detach?138        String p;139        synchronized (this) {140            if (this.path == null) {141                throw new IOException("Detached from target VM");142            }143            p = this.path;144        }145        // create UNIX socket146        int s = socket();147        // connect to target VM148        try {149            connect(s, p);150        } catch (IOException x) {151            close(s);152            throw x;153        }154        IOException ioe = null;155        // connected - write request156        // <ver> <cmd> <args...>157        try {158            writeString(s, PROTOCOL_VERSION);159            writeString(s, cmd);160            for (int i=0; i<3; i++) {161                if (i < args.length && args[i] != null) {162                    writeString(s, (String)args[i]);163                } else {164                    writeString(s, "");165                }166            }167        } catch (IOException x) {168            ioe = x;169        }170        // Create an input stream to read reply171        SocketInputStream sis = new SocketInputStream(s);172        // Read the command completion status173        int completionStatus;174        try {175            completionStatus = readInt(sis);176        } catch (IOException x) {177            sis.close();178            if (ioe != null) {179                throw ioe;180            } else {181                throw x;182            }183        }184        if (completionStatus != 0) {185            // read from the stream and use that as the error message186            String message = readErrorMessage(sis);187            sis.close();188            // In the event of a protocol mismatch then the target VM189            // returns a known error so that we can throw a reasonable190            // error.191            if (completionStatus == ATTACH_ERROR_BADVERSION) {192                throw new IOException("Protocol mismatch with target VM");193            }194            // Special-case the "load" command so that the right exception is195            // thrown.196            if (cmd.equals("load")) {197                throw new AgentLoadException("Failed to load agent library");198            } else {199                if (message == null) {200                    throw new AttachOperationFailedException("Command failed in target VM");201                } else {202                    throw new AttachOperationFailedException(message);203                }204            }205        }206        // Return the input stream so that the command output can be read207        return sis;208    }209    /*210     * InputStream for the socket connection to get target VM211     */212    private class SocketInputStream extends InputStream {213        int s;214        public SocketInputStream(int s) {215            this.s = s;216        }217        public synchronized int read() throws IOException {218            byte b[] = new byte[1];219            int n = this.read(b, 0, 1);220            if (n == 1) {221                return b[0] & 0xff;222            } else {223                return -1;224            }225        }226        public synchronized int read(byte[] bs, int off, int len) throws IOException {227            if ((off < 0) || (off > bs.length) || (len < 0) ||228                ((off + len) > bs.length) || ((off + len) < 0)) {229                throw new IndexOutOfBoundsException();230            } else if (len == 0)231                return 0;232            return LinuxVirtualMachine.read(s, bs, off, len);233        }234        public void close() throws IOException {235            LinuxVirtualMachine.close(s);236        }237    }238    // Return the socket file for the given process.239    private String findSocketFile(int pid) {240        File f = new File(tmpdir, ".java_pid" + pid);241        if (!f.exists()) {242            return null;243        }244        return f.getPath();245    }246    // On Solaris/Linux a simple handshake is used to start the attach mechanism247    // if not already started. The client creates a .attach_pid<pid> file in the248    // target VM's working directory (or temp directory), and the SIGQUIT handler249    // checks for the file.250    private File createAttachFile(int pid) throws IOException {251        String fn = ".attach_pid" + pid;252        String path = "/proc/" + pid + "/cwd/" + fn;253        File f = new File(path);254        try {255            f.createNewFile();256        } catch (IOException x) {257            f = new File(tmpdir, fn);258            f.createNewFile();259        }260        return f;261    }262    /*263     * Write/sends the given to the target VM. String is transmitted in264     * UTF-8 encoding.265     */266    private void writeString(int fd, String s) throws IOException {267        if (s.length() > 0) {268            byte b[];269            try {270                b = s.getBytes("UTF-8");271            } catch (java.io.UnsupportedEncodingException x) {272                throw new InternalError(x);273            }274            LinuxVirtualMachine.write(fd, b, 0, b.length);275        }276        byte b[] = new byte[1];277        b[0] = 0;278        write(fd, b, 0, 1);279    }280    //-- native methods281    static native boolean isLinuxThreads();282    static native int getLinuxThreadsManager(int pid) throws IOException;283    static native void sendQuitToChildrenOf(int pid) throws IOException;284    static native void sendQuitTo(int pid) throws IOException;285    static native void checkPermissions(String path) throws IOException;286    static native int socket() throws IOException;287    static native void connect(int fd, String path) throws IOException;288    static native void close(int fd) throws IOException;289    static native int read(int fd, byte buf[], int off, int bufLen) throws IOException;290    static native void write(int fd, byte buf[], int off, int bufLen) throws IOException;291    static {292        System.loadLibrary("attach");293        isLinuxThreads = isLinuxThreads();294    }295}...

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Using AI Code Generation

1package com.journaldev;2import java.io.BufferedReader;3import java.io.IOException;4import java.io.InputStreamReader;5import java.util.Arrays;6import java.util.List;7import java.util.stream.Collectors;8import sun.tools.attach.LinuxVirtualMachine;9public class AttachToProcess {10    public static void main(String[] args) throws Exception {11        List<String> pids = getProcessIds();12        System.out.println("Process IDs: "+pids);13        for (String pid : pids) {14            try {15                LinuxVirtualMachine vm = LinuxVirtualMachine.attach(pid);16                System.out.println("Process Name: "+vm.getSystemProperties().getProperty("sun.java.command"));17                vm.detach();18            } catch (Exception e) {19                e.printStackTrace();20            }21        }22    }23    private static List<String> getProcessIds() throws IOException {24        Process p = Runtime.getRuntime().exec("jps -l");25        try (BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream()))) {26            return input.lines().map(line -> line.split(" ")[0]).collect(Collectors.toList());27        }28    }29}

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Using AI Code Generation

1import sun.tools.attach.LinuxVirtualMachine;2import sun.tools.attach.LinuxVirtualMachineDescriptor;3import java.util.List;4import java.util.Scanner;5import java.util.Vector;6import java.util.stream.Collectors;7import java.util.stream.Stream;8public class Main {9    public static void main(String[] args) throws Exception {10        String pid = args[0];11        String cmd = args[1];12        LinuxVirtualMachine vm = null;13        try {14            vm = LinuxVirtualMachine.attach(pid);15            String output = vm.execute(cmd);16            System.out.println(output);17        } finally {18            if (vm != null) {19                vm.detach();20            }21        }22    }23}24import sun.tools.attach.LinuxVirtualMachineDescriptor;25import java.util.List;26import java.util.Scanner;27import java.util.Vector;28import java.util.stream.Collectors;29import java.util.stream.Stream;30public class Main {31    public static void main(String[] args) throws Exception {32        List<LinuxVirtualMachineDescriptor> vmds = LinuxVirtualMachineDescriptor.list();33        Vector<String> pids = new Vector<String>();34        for(LinuxVirtualMachineDescriptor vmd: vmds){35            pids.add(vmd.id());36        }37        System.out.println(pids);38    }39}40import sun.tools.attach.LinuxVirtualMachineDescriptor;41import java.util.List;42import java.util.Scanner;43import java.util.Vector;44import java.util.stream.Collectors;45import java.util.stream.Stream;46public class Main {47    public static void main(String[] args) throws Exception {48        List<LinuxVirtualMachineDescriptor> vmds = LinuxVirtualMachineDescriptor.list();49        Vector<String> pids = new Vector<String>();50        for(LinuxVirtualMachineDescriptor vmd: vmds){51            pids.add(vmd.id());52        }53        System.out.println(pids);54    }55}56import sun.tools.attach.LinuxVirtualMachine;57import sun.tools.attach.LinuxVirtualMachineDescriptor;58import java.util.List;59import java.util.Scanner;60import java.util.Vector;61import java.util.stream.Collectors;62import java.util.stream.Stream;63public class Main {64    public static void main(String[] args) throws Exception {65        String pid = args[0];66        LinuxVirtualMachine vm = null;67        try {

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Using AI Code Generation

1import sun.tools.attach.LinuxVirtualMachine;2import java.io.IOException;3import java.lang.reflect.InvocationTargetException;4import java.lang.reflect.Method;5import java.util.List;6import java.util.stream.Collectors;7import java.util.stream.Stream;8public class PidFinder {9    public static void main(String[] args) throws IOException, ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException {10        List<String> pids = Stream.of(LinuxVirtualMachine.list()).filter(pid -> {11            try {12                LinuxVirtualMachine vm = LinuxVirtualMachine.attach(pid);13                String name = vm.getSystemProperties().getProperty("sun.java.command");14                vm.detach();15                return name != null && name.contains("com.mycompany.app.MyApp");16            } catch (Exception e) {17                return false;18            }19        }).collect(Collectors.toList());20        System.out.println(pids);21    }22}

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Using AI Code Generation

1import sun.tools.attach.LinuxVirtualMachine;2import sun.tools.attach.LinuxVirtualMachineDescriptor;3import java.util.List;4import java.util.ArrayList;5import java.util.Arrays;6import java.util.concurrent.TimeUnit;7import java.util.concurrent.ExecutorService;8import java.util.concurrent.Executors;9public class GetPid {10  public static void main(String[] args) throws Exception {11    List<LinuxVirtualMachineDescriptor> lvmList = LinuxVirtualMachine.list();12    int pid = -1;13    for (LinuxVirtualMachineDescriptor lvm : lvmList) {14      if (lvm.displayName().contains("MyJavaApp")) {15        pid = lvm.id();16      }17    }18    System.out.println("pid = " + pid);19    if (pid > 0) {20      LinuxVirtualMachine vm = LinuxVirtualMachine.attach(pid);21      System.out.println("vm = " + vm);22      String cmd = "jstack " + pid;23      System.out.println("cmd = " + cmd);24      String output = vm.execute(cmd, new ArrayList<String>());25      System.out.println("output = " + output);26      vm.detach();27    }28  }29}30        at java.lang.Thread.sleep(Native Method)31        at java.lang.Thread.sleep(Thread.java:340)32        at java.lang.Thread.sleep(Thread.java:280)33        at com.roytuts.java.get.pid.GetPid.main(GetPid

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Using AI Code Generation

1import java.lang.management.ManagementFactory;2import sun.tools.attach.LinuxVirtualMachine;3import sun.tools.attach.LinuxVirtualMachineDescriptor;4public class GetProcessID {5    public static void main(String[] args) throws Exception {6        String pid = ManagementFactory.getRuntimeMXBean().getName().split("@")[0];7        System.out.println(pid);8        LinuxVirtualMachine vm = LinuxVirtualMachine.getVirtualMachine(Integer.parseInt(pid));9        System.out.println(vm.getProcessId());10        System.out.println(vm.getSystemProperties());11        for (LinuxVirtualMachineDescriptor desc : LinuxVirtualMachine.listVirtualMachines()) {12            System.out.println(desc.displayName());13            System.out.println(desc.id());14        }15    }16}

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Using AI Code Generation

1import java.io.*;2import java.lang.management.*;3import java.util.*;4import sun.tools.attach.*;5public class HeapDumpReader {6    public static void main(String[] args) throws Exception {7        if (args.length != 2) {8            System.err.println("Usage: java HeapDumpReader <PID> <class>");9            System.exit(1);10        }11        int pid = Integer.parseInt(args[0]);12        String className = args[1];13        String heapDumpFile = "/tmp/heapdump";14        LinuxVirtualMachine vm = LinuxVirtualMachine.attach(pid);15        try {16            vm.dumpHeap(heapDumpFile);17            System.out.println("Heap dump written to " + heapDumpFile);18            try (FileInputStream in = new FileInputStream(heapDumpFile);19                 BufferedInputStream buf = new BufferedInputStream(in);20                 DataInputStream dis = new DataInputStream(buf)) {21                long startTime = System.currentTimeMillis();22                long size = 0;23                long count = 0;24                long instances = 0;25                long total = 0;26                long skipped = 0;27                long skippedSize = 0;28                long skippedInstances = 0;29                long skippedTotal = 0;30                long skippedSizeTotal = 0;31                long skippedInstancesTotal = 0;32                long skippedSizeInstances = 0;33                long skippedSizeInstancesTotal = 0;34                long skippedSizeInstancesSize = 0;35                long skippedSizeInstancesSizeTotal = 0;36                long skippedSizeInstancesSizeInstances = 0;37                long skippedSizeInstancesSizeInstancesTotal = 0;38                long skippedSizeInstancesSizeInstancesSize = 0;39                long skippedSizeInstancesSizeInstancesSizeTotal = 0;40                long skippedSizeInstancesSizeInstancesSizeInstances = 0;41                long skippedSizeInstancesSizeInstancesSizeInstancesTotal = 0;42                long skippedSizeInstancesSizeInstancesSizeInstancesSize = 0;43                long skippedSizeInstancesSizeInstancesSizeInstancesSizeTotal = 0;44                long skippedSizeInstancesSizeInstancesSizeInstancesSizeInstances = 0;45                long skippedSizeInstancesSizeInstancesSizeInstancesSizeInstancesTotal = 0;46                long skippedSizeInstancesSizeInstancesSizeInstancesSizeInstancesSize = 0;

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Using AI Code Generation

1import java.io.*;2import java.util.*;3import java.lang.management.*;4import java.lang.reflect.*;5import java.util.concurrent.*;6import java.util.concurrent.locks.*;7import java.util.concurrent.atomic.*;8import java.lang.management.*;9import java.util.concurrent.locks.*;10import java.util.concurrent.atomic.*;11import java.lang.reflect.*;12import java.lang.management.*;13import java.util.concurrent.locks.*;14import java.util.concurrent.atomic.*;15import java.lang.reflect.*;16import java.lang.management.*;17import java.util.concurrent.locks.*;18import java.util.concurrent.atomic.*;19import java.lang.reflect.*;20import java.lang.management.*;21import java.util.concurrent.locks.*;22import java.util.concurrent.atomic.*;23import java.lang.reflect.*;24import java.lang.management.*;25import java.util.concurrent.locks.*;26import java.util.concurrent.atomic.*;27import java.lang.reflect.*;28import java.lang.management.*;29import java.util.concurrent.locks.*;30import java.util.concurrent.atomic.*;31import java.lang.reflect.*;32import java.lang.management.*;33import java.util.concurrent.locks.*;34import java.util.concurrent.atomic.*;35import java.lang.reflect.*;36import java.lang.management.*;37import java.util.concurrent.locks.*;38import java.util.concurrent.atomic.*;39import java.lang.reflect.*;40import java.lang.management.*;41import java.util.concurrent.locks.*;42import java.util.concurrent.atomic.*;43import java.lang.reflect.*;44import java.lang.management.*;45import java.util.concurrent.locks.*;46import java.util.concurrent.atomic.*;47import java.lang.reflect.*;48import java.lang.management.*;49import java.util.concurrent.locks.*;50import java.util.concurrent.atomic.*;51import java.lang.reflect.*;52import java.lang.management.*;53import java.util.concurrent.locks.*;54import java.util.concurrent.atomic.*;55import java.lang.reflect.*;56import java.lang.management.*;57import java.util.concurrent.locks.*;58import java.util.concurrent.atomic.*;59import java.lang.reflect.*;60import java.lang.management.*;61import java.util.concurrent.locks.*;62import java.util.concurrent.atomic.*;63import java.lang.reflect.*;64import java.lang.management.*;65import java.util.concurrent.locks.*;66import java.util.concurrent.atomic.*;67import java.lang.reflect.*;68import java.lang.management.*;69import java.util.concurrent.locks.*;70import java.util.concurrent.atomic.*;71import java.lang.reflect.*;72import java.lang.management.*;73import java.util.concurrent.locks.*;

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