How to display JVM HEAP and PERMGEN using JMAP

ssunel@javabender:/space/bin$ jmap -heap 4028
Attaching to process ID 4028, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.4-b02

using thread-local object allocation.
Parallel GC with 4 thread(s)

Heap Configuration:
   MinHeapFreeRatio = 40
   MaxHeapFreeRatio = 70
   MaxHeapSize      = 1073741824 (1024.0MB)
   NewSize          = 1048576 (1.0MB)
   MaxNewSize       = 4294901760 (4095.9375MB)
   OldSize          = 4194304 (4.0MB)
   NewRatio         = 2
   SurvivorRatio    = 8
   PermSize         = 16777216 (16.0MB)
   MaxPermSize      = 67108864 (64.0MB)

Heap Usage:
PS Young Generation
Eden Space:
   capacity = 31326208 (29.875MB)
   used     = 9114008 (8.691795349121094MB)
   free     = 22212200 (21.183204650878906MB)
   29.09387564559362% used
From Space:
   capacity = 10944512 (10.4375MB)
   used     = 10937848 (10.431144714355469MB)
   free     = 6664 (0.00635528564453125MB)
   99.93911103574102% used
To Space:
   capacity = 13828096 (13.1875MB)
   used     = 0 (0.0MB)
   free     = 13828096 (13.1875MB)
   0.0% used
PS Old Generation
   capacity = 54329344 (51.8125MB)
   used     = 30716608 (29.29364013671875MB)
   free     = 23612736 (22.51885986328125MB)
   56.5377855473462% used
PS Perm Generation
   capacity = 39321600 (37.5MB)
   used     = 22346712 (21.311485290527344MB)
   free     = 16974888 (16.188514709472656MB)
   56.83062744140625% used


ssunel@javabender:/space/$ jmap -permstat 4028
Attaching to process ID 4028, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.4-b02
11313 intern Strings occupying 886336 bytes.
finding class loader instances ..Finding object size using Printezis bits and skipping over...
Finding object size using Printezis bits and skipping over...
Finding object size using Printezis bits and skipping over...
Finding object size using Printezis bits and skipping over...
Finding object size using Printezis bits and skipping over...
done.
computing per loader stat ..done.
please wait.. computing liveness......................................liveness analysis may be inaccurate ...
class_loader classes bytes parent_loader alive? type

<bootstrap> 2784 12492344  null   live <internal>
0xa1655e20 1 1784  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73a52dc8 6 18072 0x7447ada0 live sun/reflect/misc/MethodUtil@0x6fce5a10
0xa1682da8 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x74406470 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0xa16830d8 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73b660b8 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x7440c5b8 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73b66160 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x74406790 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73b66128 1 1216 0x73a52dc8 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x74b86370 1 1184  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x74405e30 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0xa15be7c0 1 1992  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73b660f0 1 1184  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73a52e60 1 1824  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x7447ade8 85 405928  null   live sun/misc/Launcher$ExtClassLoader@0x6f89e7b0
0x73a52e98 1 1992  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x7447ada0 2498 8514496 0x7447ade8 live sun/misc/Launcher$AppClassLoader@0x6f8ead78
0xa1683ad0 1 1808  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73b8f2e0 0 0 0x7447ada0 dead java/util/ResourceBundle$RBClassLoader@0x6fa09738
0xa16834a8 1 1184  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x73a52e08 1 1784  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0xa15beae0 1 2008  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x74406150 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0x74407ad0 1 1184 0x7447ada0 dead sun/reflect/DelegatingClassLoader@0x6f7a9c30
0xa16837c8 1 1184  null   dead sun/reflect/DelegatingClassLoader@0x6f7a9c30

total = 27 5395 21461824    N/A     alive=4, dead=23    N/A  

Attaching jdb debugger to a Core File or Hung Process

Sample Usage :jdb -connect sun.jvm.hotspot.jdi.SAPIDAttachingConnector:pid=20441

When this Connector attaches to a process it does so in read-only mode; that is the debugger can examine threads and the running application but it cannot change anything.

Alternative debuggers and descriptions

Connector : Description
SA Core Attaching Connector : This Connector can be used by a debugger to debug a core file.
SA PID Attaching Connector : This Connector can be used by a debugger to debug a process.
SA Debug Server Attaching Connector :  This Connector can be used by a debugger to debug a process or core file on a machine other than the machine upon which the debugger is running.

ssunel@javabender:/space$ jdb -connect sun.jvm.hotspot.jdi.SAPIDAttachingConnector:pid=20441
Initializing jdb...
> threads
Group system:
(java.lang.ref.Reference$ReferenceHandler)0x23 Reference Handler
unknown
(java.lang.ref.Finalizer$FinalizerThread)0x22
Finalizer unknown
(java.lang.Thread)0x21 Signal Dispatcher running
(java.lang.Thread)0x24 main running
[... more lines removed here to reduce output ...]
Group main:
(java.lang.Thread)0x1
TP-Monitor
unknown
(com.ecyrd.jspwiki.PageManager$LockReaper)0x0 Thread-33
sleeping
> thread 0x24
main[1] where
[1] java.net.PlainSocketImpl.socketAccept (native method)
[2] java.net.PlainSocketImpl.socketAccept (native method)
[3] java.net.PlainSocketImpl.accept (PlainSocketImpl.java:384)
[4] java.net.ServerSocket.implAccept (ServerSocket.java:450)
[5] java.net.ServerSocket.accept (ServerSocket.java:421)
[6] org.apache.catalina.core.StandardServer.await (StandardServer.java:552)
[7] org.apache.catalina.startup.Catalina.await (Catalina.java:634)
[8] org.apache.catalina.startup.Catalina.start (Catalina.java:596)
[9] sun.reflect.NativeMethodAccessorImpl.invoke0 (native method)
[10] sun.reflect.NativeMethodAccessorImpl.invoke
(NativeMethodAccessorImpl.java:39)
[11] sun.reflect.DelegatingMethodAccessorImpl.invoke
(DelegatingMethodAccessorImpl.java:25)
[12] java.lang.reflect.Method.invoke (Method.java:585)
[13] org.apache.catalina.startup.Bootstrap.start (Bootstrap.java:295)
[14] org.apache.catalina.startup.Bootstrap.main (Bootstrap.java:392)
main[1] up 13
main[14] where
[14] org.apache.catalina.startup.Bootstrap.main (Bootstrap.java:392)
47
main[14] locals
Method arguments:
args = instance of java.lang.String[1] (id=40)
Local variables:
command = "start"
> help
** command list **
connectors                -- list available connectors and transports in this VM

run [class [args]]        -- start execution of application's main class

threads [threadgroup]     -- list threads
thread <thread id>        -- set default thread
suspend [thread id(s)]    -- suspend threads (default: all)
resume [thread id(s)]     -- resume threads (default: all)
where [<thread id> | all] -- dump a thread's stack
wherei [<thread id> | all]-- dump a thread's stack, with pc info
up [n frames]             -- move up a thread's stack
down [n frames]           -- move down a thread's stack
kill <thread id> <expr>   -- kill a thread with the given exception object
interrupt <thread id>     -- interrupt a thread

print <expr>              -- print value of expression
dump <expr>               -- print all object information
eval <expr>               -- evaluate expression (same as print)
set <lvalue> = <expr>     -- assign new value to field/variable/array element
locals                    -- print all local variables in current stack frame

classes                   -- list currently known classes
class <class id>          -- show details of named class
methods <class id>        -- list a class's methods
fields <class id>         -- list a class's fields

threadgroups              -- list threadgroups
threadgroup <name>        -- set current threadgroup

stop in <class id>.<method>[(argument_type,...)]
                          -- set a breakpoint in a method
stop at <class id>:<line> -- set a breakpoint at a line
clear <class id>.<method>[(argument_type,...)]
                          -- clear a breakpoint in a method
clear <class id>:<line>   -- clear a breakpoint at a line
clear                     -- list breakpoints
catch [uncaught|caught|all] <class id>|<class pattern>
                          -- break when specified exception occurs
ignore [uncaught|caught|all] <class id>|<class pattern>
                          -- cancel 'catch' for the specified exception
watch [access|all] <class id>.<field name>
                          -- watch access/modifications to a field
unwatch [access|all] <class id>.<field name>
                          -- discontinue watching access/modifications to a field
trace [go] methods [thread]
                          -- trace method entries and exits.
                          -- All threads are suspended unless 'go' is specified
trace [go] method exit | exits [thread]
                          -- trace the current method's exit, or all methods' exits
                          -- All threads are suspended unless 'go' is specified
untrace [methods]         -- stop tracing method entrys and/or exits
step                      -- execute current line
step up                   -- execute until the current method returns to its caller
stepi                     -- execute current instruction
next                      -- step one line (step OVER calls)
cont                      -- continue execution from breakpoint

list [line number|method] -- print source code
use (or sourcepath) [source file path]
                          -- display or change the source path
exclude [<class pattern>, ... | "none"]
                          -- do not report step or method events for specified classes
classpath                 -- print classpath info from target VM

monitor <command>         -- execute command each time the program stops
monitor                   -- list monitors
unmonitor <monitor#>      -- delete a monitor
read <filename>           -- read and execute a command file

lock <expr>               -- print lock info for an object
threadlocks [thread id]   -- print lock info for a thread

pop                       -- pop the stack through and including the current frame
reenter                   -- same as pop, but current frame is reentered
redefine <class id> <class file name>
                          -- redefine the code for a class

disablegc <expr>          -- prevent garbage collection of an object
enablegc <expr>           -- permit garbage collection of an object

!!                        -- repeat last command
<n> <command>             -- repeat command n times
# <command>               -- discard (no-op)
help (or ?)               -- list commands
version                   -- print version information
exit (or quit)            -- exit debugger

<class id>: a full class name with package qualifiers
<class pattern>: a class name with a leading or trailing wildcard ('*')
<thread id>: thread number as reported in the 'threads' command
<expr>: a Java(tm) Programming Language expression.
Most common syntax is supported.




Attaching a Core File 

Usage : jdb -connect sun.jvm.hotspot.jdi.SACoreAttachingConnector:javaExecutable=$JAVA_HOME/bin/java,core=core.20441

Attaching to a Remote Machine

Usage  :jdb -connect sun.jvm.hotspot.jdi.SADebugServerAttachingConnector:debugServerName=machine1

Jgroups LockService Example

import org.jgroups.*;
import org.jgroups.blocks.locking.LockService;

import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.locks.Lock;

public class TheOne {

    private volatile AtomicBoolean becomeMaster = new AtomicBoolean (false);
    private JChannel channel;
    private LockService lock_service;
    private Thread acquiringThread;
    private Thread statusPrinter;

    public static void main(String[] args) throws Exception {
        Thread.currentThread().setName("MyMainThread");
        TheOne master = new TheOne();
        master.channel = new JChannel("/home/ssunel/udp.xml");
        master.channel.connect("lock-cluster");
        master.lock_service = new LockService(master.channel);
        master.startAcquiringThread();
        master.startStatusPrinterThread();
    }

    public void startAcquiringThread() {
        acquiringThread = new Thread() {
            @Override
            public void run() {
                try {
                    Thread.currentThread().setName("MyAcquiringThread");                   
                    getLock();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        };
        acquiringThread.setDaemon(true);
        acquiringThread.start();
       
    }

    private void getLock() throws Exception{
        Lock lock = lock_service.getLock("mylock");
        lock.lock();
        becomeMaster.set(true);
        System.out.println(" -- I GOT THE LOCK !!!");
    }

    private void startStatusPrinterThread() {
        statusPrinter = new Thread(){
            @Override
            public void run() {
                Thread.currentThread().setName("MyStatusPrinterThread");                   
               
                while (true) {
                    try {
                        System.out.println("becomeMaster ? -> { " + becomeMaster + " }");
                        System.out.println("thread state ? -> { " + acquiringThread.getState() + " }");
                        sleep(2000L);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        };
        statusPrinter.setDaemon(true);
        statusPrinter.start();
    }
}

Content of UDP.XML
open the jgroups.3.1-final.jar and edit the udp.xml inside it .
Add CENTRAL_LOCK tag 

Note : DistributedLockManager is Depracated in jgroups.3.1-final release .For older release example refer to http://javabender.blogspot.com/2010/10/solving-leader-election-problem-in.html


udp.xml content will be something like this :

<!--
  Default stack using IP multicasting. It is similar to the "udp"
  stack in stacks.xml, but doesn't use streaming state transfer and flushing
  author: Bela Ban
-->

<config xmlns="urn:org:jgroups"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="urn:org:jgroups http://www.jgroups.org/schema/JGroups-3.0.xsd">
    <UDP
        mcast_port="${jgroups.udp.mcast_port:45588}"
         tos="8"
         ucast_recv_buf_size="20M"
         ucast_send_buf_size="640K"
         mcast_recv_buf_size="25M"
         mcast_send_buf_size="640K"
         loopback="true"
         level="WARN"
         log_discard_msgs="false"
         discard_incompatible_packets="true"
         max_bundle_size="64K"
         max_bundle_timeout="30"
         ip_ttl="${jgroups.udp.ip_ttl:8}"
         enable_bundling="true"
         enable_diagnostics="true"
         thread_naming_pattern="cl"

         timer_type="new"
         timer.min_threads="4"
         timer.max_threads="10"
         timer.keep_alive_time="3000"
         timer.queue_max_size="500"

         thread_pool.enabled="true"
         thread_pool.min_threads="2"
         thread_pool.max_threads="8"
         thread_pool.keep_alive_time="5000"
         thread_pool.queue_enabled="true"
         thread_pool.queue_max_size="10000"
         thread_pool.rejection_policy="discard"

         oob_thread_pool.enabled="true"
         oob_thread_pool.min_threads="1"
         oob_thread_pool.max_threads="8"
         oob_thread_pool.keep_alive_time="5000"
         oob_thread_pool.queue_enabled="false"
         oob_thread_pool.queue_max_size="100"
         oob_thread_pool.rejection_policy="Run"/>

    <PING timeout="2000"
            num_initial_members="3"/>
    <MERGE2 max_interval="30000"
            min_interval="10000"/>
    <FD_SOCK/>
    <FD_ALL/>
    <VERIFY_SUSPECT timeout="1500"  />
    <BARRIER />
    <pbcast.NAKACK exponential_backoff="300"
                   xmit_stagger_timeout="200"
                   use_mcast_xmit="false"
                   discard_delivered_msgs="true"/>
    <UNICAST />
    <pbcast.STABLE stability_delay="1000" desired_avg_gossip="50000"
                   max_bytes="4M"/>
    <pbcast.GMS print_local_addr="true" join_timeout="3000"
                view_bundling="true"/>
    <UFC max_credits="2M"
         min_threshold="0.4"/>
    <MFC max_credits="2M"
         min_threshold="0.4"/>
    <FRAG2 frag_size="60K"  />
    <pbcast.STATE_TRANSFER />
    <CENTRAL_LOCK />
    <!-- pbcast.FLUSH  /-->
</config>

How to @Consume MediaType.APPLICATION_JSON with Jersey

Sit Back And get REST...

 Blahh Blahh Blahh and the Code !







    @GET
    @Path(value = "/json")
    @Produces(MediaType.APPLICATION_JSON)
    public JSON getJSON() {
        JSON json = new JSON();
        json.setName("json");
        json.setSurname("gson");
        json.setAge(32);
        json.setHasCar(true);
        json.setMarried(true);
        json.setSalary(123L);

        List childs = new ArrayList();
        childs.add("serkan");
        childs.add("volkan");
        childs.add("aybars");
        json.setChilds(childs);

        return json;
    }

    @PUT
    @Path(value = "/pson")
    @Consumes( { MediaType.APPLICATION_JSON })   
    @Produces( { MediaType.TEXT_PLAIN })   
    public String consumeJSONObject (JSON  pson) {
        System.out.println("Consumed json object is : " + pson);
        return pson.toString();
    }



import java.util.List;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class JSON {

    private String name;
    private String surname;
    private Integer age;
    private long salary;
    private boolean isMarried;
    private boolean hasCar;
    private List childs;
    
    public JSON() {
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSurname() {
        return surname;
    }

    public void setSurname(String surname) {
        this.surname = surname;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public long getSalary() {
        return salary;
    }

    public void setSalary(long salary) {
        this.salary = salary;
    }

    public boolean isMarried() {
        return isMarried;
    }

    public void setMarried(boolean isMarried) {
        this.isMarried = isMarried;
    }

    public boolean isHasCar() {
        return hasCar;
    }

    public void setHasCar(boolean hasCar) {
        this.hasCar = hasCar;
    }

    public List getChilds() {
        return childs;
    }

    public void setChilds(List childs) {
        this.childs = childs;
    }

    @Override
    public String toString() {
        return "JSON [name=" + name + ", surname=" + surname + ", age=" + age
                + ", salary=" + salary + ", isMarried=" + isMarried
                + ", hasCar=" + hasCar + ", childs=" + childs + "]";
    }
    
} 

Json data in soapui : {"name":"json","surname":"gson","married":true,"age":32,"salary":123,"hasCar":true,"childs":["serkan","volkan","aybars"]}

note : Using Jersey 1.8 ! (really important)

Line number information for SLF4J and LOG4J log messages

Briefly;

Line number information should be put into the log messages by processing classes and enhancing the byte code.


#Ant task definition and usage can be like below. Feel free to customize according to your requirements


<taskdefname="enhanceLogs"classname="your.lovely.company.LoggerEnhancement"classpathref="lib.ant.path"/>

<enhanceLogs classesDir="${classesDir}"loggerJarsDirectory="${logging.jars.dir}"/>

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

import javassist.CannotCompileException;
import javassist.ClassPool;
import javassist.CtClass;
import javassist.expr.ExprEditor;
import javassist.expr.MethodCall;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Task;

public class LoggerEnhancement extends Task {
    public String classesDir;
    public String loggerJarsDirectory;

    public String getLoggerJarsDirectory() {
        returnthis.loggerJarsDirectory;
    }

    public voidsetLoggerJarsDirectory(final String loggerJarsDirectory) {
        this.loggerJarsDirectory= loggerJarsDirectory;
    }

    public String getClassesDir() {
        returnthis.classesDir;
    }

    public voidsetClassesDir(final String classesDir) {
        this.classesDir= classesDir;
    }

    @Override
    public voidexecute() throws BuildException {
        try{
            this.enhanceClasses();
        } catch(final Exception e) {
            e.printStackTrace();
            throw new BuildException(e);
        }
    }

    private voidenhanceClasses() throws FileNotFoundException, Exception {
        finalList classFiles = this.getClassFiles(this.classesDir);
        for(final File file : classFiles) {
            String qualifiedClassName = file.toString().substring(this.classesDir.length() + 1, file.toString().length() - 6);
            qualifiedClassName = qualifiedClassName.replaceAll("\\\\", ".");
            this.enhanceClassFile(qualifiedClassName);
        }
    }

    private voidenhanceClassFile(final String className) throws Exception {
        finalClassPool pool = ClassPool.getDefault();
        pool.appendClassPath(this.classesDir);
        pool.appendClassPath(this.loggerJarsDirectory+ "\\" + "slf4j-api-1.6.1.jar");
        pool.appendClassPath(this.loggerJarsDirectory+ "\\" + "org.apache.log4j_1.2.15.v201005080500.jar");
        finalCtClass compiledClass = pool.get(className);
        if(compiledClass == null) {
            System.err.println("Class " + className + " not found");
        } else{
            final LoggerEnhancementExpEditor exp = new LoggerEnhancementExpEditor();
            exp.setClaz(compiledClass);
            compiledClass.instrument(exp);
            compiledClass.writeFile(this.classesDir);
        }
    }

    private List getClassFiles(final String classesDir) throws FileNotFoundException {
        finalList result = new ArrayList();

        finalFile startingDirectory = new File(classesDir);
        finalList files = this.getFileListing(startingDirectory);
        System.out.println(" -- Processing classes under directory:" + classesDir);
        for(final File file : files) {
            if (file.isFile() && file.getName().endsWith(".class")) {
                result.add(file);
            }
        }
        returnresult;
    }

    private List getFileListing(final File aStartingDir) throws FileNotFoundException {
        this.validateDirectory(aStartingDir);
        finalList result = this.getFileListingNoSort(aStartingDir);
        Collections.sort(result);
        returnresult;
    }

    private List getFileListingNoSort(final File aStartingDir) throws FileNotFoundException {
        finalList result = new ArrayList();
        finalFile[] filesAndDirs = aStartingDir.listFiles();
        finalList filesDirs = Arrays.asList(filesAndDirs);
        for(final File file : filesDirs) {
            result.add(file);
            if (!file.isFile()) {
                final List deeperList = this.getFileListingNoSort(file);
                result.addAll(deeperList);
            }
        }
        returnresult;
    }

    private voidvalidateDirectory(final File aDirectory) throws FileNotFoundException {
        if(aDirectory == null) {
            throw new IllegalArgumentException("Directory should not be null.");
        }
        if(!aDirectory.exists()) {
            throw new FileNotFoundException("Directory not exist: " + aDirectory.getAbsolutePath());
        }
        if(!aDirectory.isDirectory()) {
            throw new IllegalArgumentException("Is not a directory: " + aDirectory);
        }
        if(!aDirectory.canRead()) {
            throw new IllegalArgumentException("Directory cannot be read: " + aDirectory);
        }
    }

    static classLoggerEnhancementExpEditor extends ExprEditor {
        privateCtClass claz;

        publicCtClass getClaz() {
            return this.claz;
        }

        publicvoid setClaz(final CtClass claz) {
            this.claz= claz;
        }

        @Override
        publicvoid edit(final MethodCall m) throws CannotCompileException {

            if (this.isLoggerMethodCall(m)) {
                try {
                    System.out.println("      -- Enhancing log line: "
                                       + this.getClaz().getName()
                                       + "."
                                       + m.where().getName()
                                       + "("
                                       + this.getClaz().getSimpleName()
                                       + ".java:"
                                       + m.getLineNumber()
                                       + ")");

                    m.replace("{ $1 = $1 +\", "
                              + this.getClaz().getName()
                              + "."
                              + m.where().getName()
                              + "("
                              + this.getClaz().getSimpleName()
                              + ".java:"
                              + m.getLineNumber()
                              + ") "
                              + "\"; $_ = $proceed($$); }");
                } catch (final Exception e) {
                    throw new CannotCompileException(e);
                }
            }
        }

        privateboolean isLoggerMethodCall(final MethodCall m) {
            return this.isSlf4jLoggerMethod(m) || this.isLog4jLoggerMethod(m);
        }

        privateboolean isSlf4jLoggerMethod(final MethodCall m) {
            return m.getClassName().equals("org.slf4j.Logger") && this.isALogMethod(m);
        }

        privateboolean isLog4jLoggerMethod(final MethodCall m) {
            return m.getClassName().equals("org.apache.log4j.Logger") && this.isALogMethod(m);
        }

        privateboolean isALogMethod(final MethodCall m) {
            boolean result = false;

            final String[] slf4LogLevels = { "trace", "debug", "info", "warn", "error", "fatal" };
            final String methodName = m.getMethodName();
            for (final String logLevel : slf4LogLevels) {
                if (methodName.equals(logLevel)) {
                    result = true;
                }
            }
            return result;
        }

    }

}