I want to unpack resources from my jar file. The structure of jar looks like this:
my.jar
META-INF
resources
my.exe
my.dll
my
namespace
UnpackResourceFromThisClass.class
I want to unpack my.exe and my.dll from jar file. I tried to unpack those files using this code:
try {
InputStream is = getClass().getResourceAsStream("/resources/my.exe")
OutputStream os = new FileOutputStream(new File(destDir))
Files.copy(is, os)
os.close()
is.close()
}
catch (NullPointerException e) {
e.printStackTrace();
}
catch (FileNotFoundException e) {
e.printStackTrace();
}
catch (SecurityException e) {
e.printStackTrace();
}
but it doesn't work. Any ideas? As a result I get this error:
java.lang.NullPointerException
at java.nio.file.Files.provider(Files.java:65)
at java.nio.file.Files.newInputStream(Files.java:106)
at java.nio.file.Files.copy(Files.java:2884)
at java_nio_file_Files$copy.call(Unknown Source)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:42)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:120)
at pl.ydp.gradle.Is2k8Task.getResources(Is2k8Task.groovy:84)
at pl.ydp.gradle.Is2k8Task.build(Is2k8Task.groovy:30)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:90)
at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:233)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1047)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:877)
at org.gradle.api.internal.BeanDynamicObject$MetaClassAdapter.invokeMethod(BeanDynamicObject.java:216)
This is groovy code which will be used in gradle custom task.
You seem to be writing Java... Not sure if this will get you round your problem, but the above could be written in Groovy as:
this.getClass().getResource( '/resources/my.exe' ).withInputStream { ris ->
new File( destDir ).withOutputStream { fos ->
fos << ris
}
}
Delete the leading slash, getResourceAsStream will use the absolute path if the first character is a slash.
Related
I tried to connect and download a file from a Linux server but faced the following exception when connecting to the server using the jscape java library.
Code
package com.example.util;
import com.jscape.inet.sftp.Sftp;
import com.jscape.inet.ssh.util.SshParameters;
public class TestFTPManager
{
private static final String hostname = "mycompany.example.com";
private static final String username = "exampleuser";
private static final String password = "examplepassword";
private static final int port = 22;
private Sftp sftpClient;
public TestFTPManager()
{
this.sftpClient = new Sftp( new SshParameters(hostname, port, username, password ));
}
public void connect() throws Exception
{
this.sftpClient.connect();
}
public void setAscii() throws Exception
{
this.sftpClient.setAscii();
}
public void setBinary() throws Exception
{
this.sftpClient.setBinary();
}
public Sftp getSftpClient()
{
return sftpClient;
}
public void setSftpClient( Sftp sftpClient )
{
this.sftpClient = sftpClient;
}
public static void main(String[] args)
{
try
{
TestFTPManager sftpManager = new TestFTPManager();
sftpManager.getSftpClient().connect(); // Error
System.out.println( "Connection successful!" );
// download operation is done here.
sftpManager.getSftpClient().disconnect();
System.out.println( "Disconnection successful!" );
} catch (Exception e)
{
e.printStackTrace();
}
}
}
Error
com.jscape.inet.sftp.SftpException: cause: java.util.NoSuchElementException: no common elements found
at com.jscape.inet.sftp.SftpConfiguration.createClient(Unknown Source)
at com.jscape.inet.sftp.Sftp.connect(Unknown Source)
at com.jscape.inet.sftp.Sftp.connect(Unknown Source)
at com.example.util.TestFTPManager.main(TestFTPManager.java:54)
Caused by: com.jscape.inet.ssh.transport.TransportException: cause: java.util.NoSuchElementException: no common elements found
at com.jscape.inet.ssh.transport.AlgorithmSuite.<init>(Unknown Source)
at com.jscape.inet.ssh.transport.TransportClient.getSuite(Unknown Source)
at com.jscape.inet.ssh.transport.Transport.exchangeKeys(Unknown Source)
at com.jscape.inet.ssh.transport.Transport.exchangeKeys(Unknown Source)
at com.jscape.inet.ssh.transport.TransportClient.<init>(Unknown Source)
at com.jscape.inet.ssh.transport.TransportClient.<init>(Unknown Source)
at com.jscape.inet.ssh.SshConfiguration.createConnectionClient(Unknown Source)
at com.jscape.inet.ssh.SshStandaloneConnector.openConnection(Unknown Source)
... 4 more
Caused by: java.util.NoSuchElementException: no common elements found
at com.jscape.inet.ssh.types.SshNameList.getFirstCommonNameFrom(Unknown Source)
at com.jscape.inet.ssh.transport.AlgorithmSuite.a(Unknown Source)
at com.jscape.inet.ssh.transport.AlgorithmSuite.h(Unknown Source)
... 12 more
However, when I commented down the following lines (lines no 23,23,25) in the /etc/ssh/sshd_config file in the server. I could successfully connect and download the file from the server without any exceptions.
Question: How to get rid of getting this exception without commenting down (lines no 23,23,25) the /etc/ssh/sshd_config file in the server? I would appreciate having an explanation why I get this exception too.
If you are facing this issue please check the following findings.
I used JSCAPE (Java) library version 8.8.0. According to my understanding, this version is not supported some of the Ciphers and KexAlgorithms specified in the sshd_config file.
When you refer to the JSCAPE documentation, com.jscape.inet.sftp class contains what you need to set key exchanges, ciphers, macs and compressions if needed. Please click here to see the official documentation, there you can see how you can put these things into code.
However, the JSCAPE (Java) library that I use (version 8.8.0) does not contain these classes and methods to set key exchanges, ciphers, macs and compressions if needed.
One of the things you can try is to use the latest version of the JSCAPE library, but I doubt it is available for free.
I try to evaluate math expression in string form using scriptengine, but it throws me NullPointerException
java.lang.NullPointerException
at Math.main(Math.java:12)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at edu.rice.cs.drjava.model.compiler.JavacCompiler.runCommand(JavacCompiler.java:272)
Here is the code:
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Math{
public static void main(String[] args){
ScriptEngineManager mgr = new ScriptEngineManager();
ScriptEngine jsEngine = mgr.getEngineByName("JavaScript");
try {
System.out.println("scriptEngine result: "+jsEngine.eval("{2+4*3*[1+(1+2+4)]}"));
} catch (ScriptException ex) {
Logger.getLogger(Math.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
i tried the same code in netbeans and it works, but i also need it to work in DrJava development environment.
Is it possible to resolve this or is there any other library that can evaluate string like this with combination of all parenthesis "{[()]}"?
I am using Apache POI for reading excel file (in xls and xlsx format).
It runs fine in IDE (I am using IntelliJ), but when I make the project to JAR, it can't read the excel file. I tried by giving full path of excel file, but not working.
File name spelling is right, file is not protected or read only format. Everything is good until I run JAR.
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(Unknown Source)
at com.sun.javafx.application.LauncherImpl.launchApplication(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.launcher.LauncherHelper$FXHelper.main(Unknown Source)
Caused by: java.lang.NoClassDefFoundError: org/apache/poi/hssf/usermodel/HSSFWorkbook
at TakeInput.Take(TakeInput.java:25)
at MainGUI.main(MainGUI.java:53)
... 11 more
Caused by: java.lang.ClassNotFoundException: org.apache.poi.hssf.usermodel.HSSFWorkbook
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 13 more
Exception running application MainGUI
Here is my TakeInput Class:
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import java.io.*;
import java.util.Arrays;
import java.util.Comparator;
import java.util.StringTokenizer;
public class TakeInput {
public void Take() throws Exception{
System.out.println("Inside TakeInput class..");
File f = new File("courses.xls");
FileInputStream fs = new FileInputStream(f);
HSSFWorkbook wb = new HSSFWorkbook(fs);
HSSFSheet sheet = wb.getSheetAt(0);
int CSECourseCounter=0;
for(int i=0;i<=sheet.getLastRowNum();i++){
String tempCode = sheet.getRow(i).getCell(0).getStringCellValue();
StringTokenizer tok = new StringTokenizer(tempCode);
String codeTok=tok.nextToken();
if(codeTok.equals("CSE") || codeTok.equals("CSI")) {
CSECourseCounter++;
}
}
CourseInfo[] courses = new CourseInfo[CSECourseCounter];
for(int i=0;i<CSECourseCounter;i++)
courses[i]=new CourseInfo();
System.out.println(sheet.getLastRowNum());
for(int i=0,j=0;i<=sheet.getLastRowNum();i++){
String tempCode = sheet.getRow(i).getCell(0).getStringCellValue();
StringTokenizer tok = new StringTokenizer(tempCode);
String codeTok=tok.nextToken();
if(codeTok.equals("CSE") || codeTok.equals("CSI")) {
courses[j].code = sheet.getRow(i).getCell(0).getStringCellValue();
courses[j].title = sheet.getRow(i).getCell(1).getStringCellValue();
courses[j].section = sheet.getRow(i).getCell(2).getStringCellValue();
courses[j].day = sheet.getRow(i).getCell(4).getStringCellValue();
courses[j].time = sheet.getRow(i).getCell(5).getStringCellValue();
//courses[i].room = sheet.getRow(i).getCell(6).getNumericCellValue();
//System.out.println(courses[j].code);
j++;
//CSECourseCounter++;
}
}
Arrays.sort(courses, new Comparator<CourseInfo>() {
#Override
public int compare(CourseInfo o1, CourseInfo o2) {
return o1.title.compareTo(o2.title);
}
});
System.out.println("CSE courses = "+CSECourseCounter);
for(int i=0;i<CSECourseCounter;i++){
courses[i].setCampus();
courses[i].setLabCLassAndTimeSlot();
courses[i].setDay();
}
//***************************** CourseInfo to a linked list ******************
for(int i=0;i<courses.length;i++){
CourseToLinkedList temp = AddSearchCourse.searchCourse(courses[i].code);
if(temp==null) {
AddSearchCourse.addCourse(courses[i].title,courses[i].code,courses[i].islabClass);
CourseToLinkedList temp1 = AddSearchCourse.searchCourse(courses[i].code);
temp1.addSections(courses[i].code,courses[i].title,courses[i].section,courses[i].day,courses[i].time,
courses[i].timeStart,courses[i].timeEnd,courses[i].room,
courses[i].faculty,courses[i].credit,courses[i].assigned,
courses[i].campus,courses[i].dept,courses[i].islabClass,
courses[i].timeSlot,courses[i].labTimeSlot,courses[i].day1,courses[i].day2
);
}
else{
CourseToLinkedList temp1 = AddSearchCourse.searchCourse(courses[i].code);
temp1.addSections(courses[i].code,courses[i].title,courses[i].section,courses[i].day,courses[i].time,
courses[i].timeStart,courses[i].timeEnd,courses[i].room,
courses[i].faculty,courses[i].credit,courses[i].assigned,
courses[i].campus,courses[i].dept,courses[i].islabClass,
courses[i].timeSlot,courses[i].labTimeSlot,courses[i].day1,courses[i].day2
);
}
}
System.out.println("outside try catch..");
}
}
I put a copy of this excel file which is in the project folder to that folder where JAR file situated. No problem with location.
As I can see the logs, this issue may happen because of dependency jars for your code. try to add the jar(may be 'jakarta-poi-version.jar') having class 'HSSFWorkbook' into your class path and then try to run it again.
I am trying to import some guest layouts from a larFile(exported from another instance) in to a liferay instance (can be an already installed_and_configured OR can be a fresh installation) by creating a class which extends SimpleAction in a Start up Hook ( ) and then pointing 'application.startup.events' to this class in the portal-ext.properties file. I want this to run every time the server starts as my larFile version may change over the time. My Code is as follows...
File larFile=new File("/Users/grai001/Desktop/default_guest_public_new_light.lar");
//using absolute path for now -need help in accessing the relative path to ${liferay.home}??
Group guestGroup = GroupLocalServiceUtil.getGroup(1, GroupConstants.GUEST);
LayoutLocalServiceUtil.importLayouts(guestGroup.getCreatorUserId(), guestGroup.getGroupId(), false, new HashMap<String,String[]>(), larFile);
//I want them to be a public layouts which are visible to every one even when a user is not logged in - like the default WHAT-WE-DO kind ofpages in liferay6.1 - I am using 6.1GA2 at both ends
How ever this is giving me null pointer exception and the stack trace is as below..
com.liferay.portal.kernel.exception.SystemException: java.lang.NullPointerException
at com.liferay.portal.service.impl.LayoutLocalServiceImpl.importLayouts(LayoutLocalServiceImpl.java:1398)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:122)
at com.liferay.portal.service.impl.LayoutLocalServiceVirtualLayoutsAdvice.invoke(LayoutLocalServiceVirtualLayoutsAdvice.java:197)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.service.impl.LayoutLocalServiceStagingAdvice.invoke(LayoutLocalServiceStagingAdvice.java:107)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.transaction.TransactionInterceptor.invoke(TransactionInterceptor.java:71)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.security.pacl.PACLAdvice.invoke(PACLAdvice.java:51)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ServiceBeanAopProxy.invoke(ServiceBeanAopProxy.java:211)
at $Proxy27.importLayouts(Unknown Source)
at com.liferay.portal.service.LayoutLocalServiceUtil.importLayouts(LayoutLocalServiceUtil.java:1037)
at com.walmart.services.mpportal.liferay.startup.StartupHook.run(StartupHook.java:88)
at com.liferay.portal.events.EventsProcessorImpl.processEvent(EventsProcessorImpl.java:106)
at com.liferay.portal.events.EventsProcessorImpl.process(EventsProcessorImpl.java:58)
at com.liferay.portal.events.EventsProcessorUtil.process(EventsProcessorUtil.java:53)
at com.liferay.portal.util.PortalInstances._initCompany(PortalInstances.java:462)
at com.liferay.portal.util.PortalInstances.initCompany(PortalInstances.java:92)
at com.liferay.portal.servlet.MainServlet.initCompanies(MainServlet.java:798)
at com.liferay.portal.servlet.MainServlet.init(MainServlet.java:355)
at javax.servlet.GenericServlet.init(GenericServlet.java:160)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1266)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1185)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1080)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5015)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5302)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:895)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:871)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:615)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:649)
at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1585)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:439)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:680)
Caused by: java.lang.NullPointerException
at com.liferay.portal.kernel.util.ParamUtil.getLong(ParamUtil.java:616)
at com.liferay.portal.service.impl.LayoutLocalServiceStagingAdvice.deleteLayout(LayoutLocalServiceStagingAdvice.java:70)
at com.liferay.portal.service.impl.LayoutLocalServiceStagingAdvice.invoke(LayoutLocalServiceStagingAdvice.java:113)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.transaction.TransactionInterceptor.invoke(TransactionInterceptor.java:71)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ChainableMethodAdvice.invoke(ChainableMethodAdvice.java:57)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.security.pacl.PACLAdvice.invoke(PACLAdvice.java:51)
at com.liferay.portal.spring.aop.ServiceBeanMethodInvocation.proceed(ServiceBeanMethodInvocation.java:118)
at com.liferay.portal.spring.aop.ServiceBeanAopProxy.invoke(ServiceBeanAopProxy.java:211)
at $Proxy27.deleteLayout(Unknown Source)
at com.liferay.portal.service.LayoutLocalServiceUtil.deleteLayout(LayoutLocalServiceUtil.java:435)
at com.liferay.portal.lar.LayoutImporter.deleteMissingLayouts(LayoutImporter.java:196)
at com.liferay.portal.lar.LayoutImporter.doImportLayouts(LayoutImporter.java:774)
at com.liferay.portal.lar.LayoutImporter.importLayouts(LayoutImporter.java:147)
at com.liferay.portal.service.impl.LayoutLocalServiceImpl.importLayouts(LayoutLocalServiceImpl.java:1382)
... 50 more
And now doing LayoutLocalServiceUtil.importLayouts(guestGroup.getCreatorUserId(), guestGroup.getGroupId(), true, new HashMap<String,String[]>(), larFile);
ie...importing them as private layouts is working fine - unfortunately I want them to be public and be visible to every one. Also logging in as portal adminstrator and
importing from the UI as public layouts is working well and good. How ever I want this to be done in an automated way.
Trying to solve this problem of mine from the past 1 week - did enough research - but still couldn't. Any kind of help is appreciated..!
Thanks in advance
public void larTest() {
LiferayFacesContext liferayFacesContext = LiferayFacesContext
.getInstance();
ActionRequest request = (ActionRequest) liferayFacesContext
.getPortletRequest();
ThemeDisplay td = (ThemeDisplay) request
.getAttribute(WebKeys.THEME_DISPLAY);
long userId = td.getUserId();
long groupId = td.getScopeGroupId();
File larFile=new File("C:\\Users\\youssef\\dahar\\Downloads\\ok.lar");
//using absolute path for now -need help in accessing the relative path to ${liferay.home}??
Group guestGroup = null;
try {
guestGroup = GroupLocalServiceUtil.getGroup(groupId);
} catch (Exception e) {
System.out.println("catch 1");
e.printStackTrace();
}
try {
LayoutLocalServiceUtil.importLayouts(guestGroup.getCreatorUserId(), guestGroup.getGroupId(), false, new HashMap<String,String[]>(), larFile);
} catch (PortalException e) {
System.out.println("catch 2");
e.printStackTrace();
} catch (SystemException e) {
System.out.println("catch 3");
e.printStackTrace();
}
//I want them to be a public layouts which are visible to every one even when a user is not logged in - like the default WHAT-WE-DO kind ofpages in liferay6.1 - I am using 6.1GA2 at both ends
}
may be can help you this function
it worked for me sometimes and sometimes no :)
Updated:
This is true not only for AsyncAppender. Happens for console one as well.
I faced with wierd behavior of AsyncAppender that occurs rarely but with sufficient harm.
Here is code snippet:
public void testNPE() {
try {
try {
throw new NullPointerException();
} catch (NullPointerException e) {
throw new RuntimeException(e);
}
} catch (RuntimeException e) {
logger.error("Catcha!" + e.getLocalizedMessage(), e);
}
}
Probable result should be:
07.12.12 10:21:34,904 ERROR [main] >> [com.ubs.eqdel.markitfeed.core.RetrieverTest:74] Catcha! java.lang.NullPointerException
java.lang.RuntimeException: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:71)
...
Caused by: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:69)
... 25 more
But for 5 of 20 attempts I see:
Exception in thread "Dispatcher-Thread-0" java.lang.NullPointerException
at java.io.Writer.write(Writer.java:140)
at org.apache.log4j.helpers.CountingQuietWriter.write(CountingQuietWriter.java:45)
at org.apache.log4j.WriterAppender.subAppend(WriterAppender.java:309)
at org.apache.log4j.RollingFileAppender.subAppend(RollingFileAppender.java:263)
at org.apache.log4j.WriterAppender.append(WriterAppender.java:160)
at org.apache.log4j.AppenderSkeleton.doAppend(AppenderSkeleton.java:251)
at org.apache.log4j.helpers.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:66)
at org.apache.log4j.AsyncAppender$Dispatcher.run(AsyncAppender.java:583)
at java.lang.T07.12.12 10:23:54,972 ERROR [main] >> [com.ubs.eqdel.markitfeed.core.RetrieverTest:74] Catcha! java.lang.NullPointerException
java.lang.RuntimeException: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:71)
...
Caused by: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:69)
... 25 more
What's wrong with AsyncAppender? Did anybody face the same? And what is the workaround on this?
Looks like this bug.
Edit: Based on the release notes, 1.2.16 (released on 2010-04-06) should contain the fix for this.