Spring Batch Samples

Several examples of Spring Batch:

https://github.com/devwebcl/spring-batch

Simple HTTP Server

python -m SimpleHTTPServer 8000

if you face :
/usr/bin/python: No module named SimpleHTTPServer

it's because for python 3:

python3 -m http.server 8000

Cannot retrieve WLS app info

Cannot retrieve:

The configuration for app is still being loaded from your last request, please wait a moment and retry.

####<Oct 30, 2017 9:59:44 AM CLT> <Error> <Console> <lablnx297> <AdminServer> <[ACTIVE] ExecuteThread: '5' for queue: 'weblogic.kernel.Default (self-tuning)'> <weblogic> <> <cc19eb40-e1ae-46e5-80cb-dbf2a3509811-00000f0c> <1509368384819> <BEA-240003> <Administration Console encountered the following error: java.lang.NullPointerException
  at weblogic.application.internal.ApplicationRuntimeMBeanImpl.getComponentRuntimes(ApplicationRuntimeMBeanImpl.java:449)
  at sun.reflect.GeneratedMethodAccessor1348.invoke(Unknown Source)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:606)
  at weblogic.management.jmx.modelmbean.WLSModelMBean.getAttribute(WLSModelMBean.java:525)
  at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)
  at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)
  at weblogic.management.jmx.mbeanserver.WLSMBeanServerInterceptorBase$12.run(WLSMBeanServerInterceptorBase.java:326)
  at java.security.AccessController.doPrivileged(Native Method)
  at weblogic.management.jmx.mbeanserver.WLSMBeanServerInterceptorBase.getAttribute(WLSMBeanServerInterceptorBase.java:324)
  at weblogic.management.mbeanservers.internal.JMXContextInterceptor.getAttribute(JMXContextInterceptor.java:157)
  at weblogic.management.jmx.mbeanserver.WLSMBeanServerInterceptorBase$12.run(WLSMBeanServerInterceptorBase.java:326)
  at java.security.AccessController.doPrivileged(Native Method)
  at weblogic.management.jmx.mbeanserver.WLSMBeanServerInterceptorBase.getAttribute(WLSMBeanServerInterceptorBase.java:324)
  at weblogic.management.mbeanservers.internal.SecurityInterceptor.getAttribute(SecurityInterceptor.java:300)
  at weblogic.management.jmx.mbeanserver.WLSMBeanServer.getAttribute(WLSMBeanServer.java:279)
  at weblogic.management.mbeanservers.internal.JMXConnectorSubjectForwarder$5$1.run(JMXConnectorSubjectForwarder.java:327)
  at java.security.AccessController.doPrivileged(Native Method)
  at weblogic.management.mbeanservers.internal.JMXConnectorSubjectForwarder$5.run(JMXConnectorSubjectForwarder.java:325)
  at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363)
  at weblogic.management.mbeanservers.internal.JMXConnectorSubjectForwarder.getAttribute(JMXConnectorSubjectForwarder.java:320)
  at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468)
  at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:97)
  at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1332)
  at java.security.AccessController.doPrivileged(Native Method)
  at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1431)
  at javax.management.remote.rmi.RMIConnectionImpl.getAttribute(RMIConnectionImpl.java:661)
  at javax.management.remote.rmi.RMIConnectionImpl_WLSkel.invoke(Unknown Source)
  at weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:701)
  at weblogic.rmi.internal.BasicServerRef$1.run(BasicServerRef.java:527)
  at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363)
  at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:146)
  at weblogic.rmi.internal.BasicServerRef.handleRequest(BasicServerRef.java:523)
  at weblogic.rmi.internal.wls.WLSExecuteRequest.run(WLSExecuteRequest.java:118)
  at weblogic.work.ExecuteThread.execute(ExecuteThread.java:311)
  at weblogic.work.ExecuteThread.run(ExecuteThread.java:263)
>

HTTP Cluster WebLogic Server

Old Deprecated feature:

web.xml :

<servlet><servlet-name>ProxyServlet</servlet-name>
<servlet-class>weblogic.servlet.proxy.HttpProxyServlet</servlet-class>
<init-param>
<param-name>redirectURL</param-name>
<param-value>http://localhost:8080</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>ProxyServlet</servlet-name>
<url-pattern>/MyProducerApp/*</url-pattern>
</servlet-mapping>

.

Clear Cache WLS

Before deleting any directory, you need to shutdown all servers first.

The following provides a generic example path to the tmp directory in question:

WINDOWS: 
cd C:\wls\user_projects\domains\servers\

UNIX:
cd /wls/user_projects/domains/servers/

The following would be used to clear the cache:

WINDOWS:  
rd C:\wls\user_projects\domains\servers\tmp
rd C:\wls\user_projects\domains\servers\cache

UNIX: 
rm -rf /wls/user_projects/domains/servers/tmp
rm -rf /wls/user_projects/domains//servers/cache


 For WLS versions 9.2 and above, delete the following Admin and Managed server cache directories:

    /servers/cache
    /servers/stage (if exists)
    /servers/tmp
 

WLS JMS Configuration

Essential steps to configure a JMS environment


CORE_WLS_Domain --> Services --> Persistent Stores -->

New:

Name: FileStore-Mensajeria1
Target: Managed Server 1 (WLS01)
Directory: jmsMensajeria_1
(Activate Changes)

Name: FileStore-Mensajeria2
Target: Managed Server 2 (WLSS02)
Directory: jmsMensajeria_2
(Activate Changes)


CORE_WLS_Domain --> Services --> Messaging --> JMS Servers

New:

Name: JMSServer-Mensajeria_1
Persistent Store: FileStore-Mensajeria1
Target: WLS01 (migratable)
(finish)

Name: JMSServer-Mensajeria_2
Persistent Store: FileStore-Mensajeria2
Target: WLS02 (migratable)
(finish)

(Activate Changes)


CORE_WLS_Domain --> Services --> Messaging --> JMS Modules

Name: JMSModule_Mensajeria
Target: wls_core_cluster
(next/finish)
(Activate Changes)


entrar a JMS Module creado: (crear subdeployment)
CORE_WLS_Domain --> Services --> Messaging --> JMS Modules --> JMSModule_Mensajeria --> Subdeployments

New:

name: MensajeriaSubdeployment
Target: JMSServer-Mensajeria_1, JMSServer-Mensajeria_2
(Activate Changes)


CORE_WLS_Domain --> Services --> Messaging --> JMS Modules --> JMSModule_Mensajeria

New:

Connection Factory (next)

Name: ConnectionFactory-Mensajeria
JNDI Name: jms/ConnectionFactory-Mensajeria (next)
(finish)
(Activate Changes)

New:

Distributed Queue (next)

Name: DistributedQueue-Mensajeria
JNDI Name: jms/journal-standar (next)
Advanced Targeting: MensajeriaSubdeployment

JMS Servers: JMSServer-Mensajeria_1, JMSServer-Mensajeria_2
(finish)
(Activate Changes)

Opatch WLS 12c

Backup Oracle Home:
It is highly recommended that you back up the Oracle home before any patch operation. You can back up the Oracle home using your preferred method. You can use any method such as zip, cp -r, tar, and cpio to compress the Oracle home.

Opatch path:
/Users/German/Oracle/Middleware/Oracle_Home/OPatch

List patches:
./opatch lsinventory
./opatch lsinventory -detail

Check if it's feasible:
./opatch apply /Users/German/tmp/patches/23639929 -report

if the next message appears:

JAVA_HOME is not set or does not exist

then add (jre path) :

-jre /Library/Java/JavaVirtualMachines/jdk1.7.0_201.jdk/Contents/Home

Apply patch:
./opatch apply /Users/German/tmp/patches/23639929

Rollback patch
./opatch rollback -id 23639929

logs:

ORACLE_HOME/cfgtoollogs/opatch/

More info:
https://docs.oracle.com/middleware/1213/core/OPATC/toc.htm

Too many open files

The following problem may occurr in WLS:

Caused By: java.net.SocketException: Too many open files
  at java.net.Socket.createImpl(Socket.java:447)
  at java.net.Socket.connect(Socket.java:577)
  at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:161)
  at oracle.net.nt.ConnOption.connect(ConnOption.java:159)
  at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:428)
  at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:506)
  at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:595)
  at oracle.net.ns.NSProtocol.connect(NSProtocol.java:230)

This is a common issue when  File Descriptors are not enough for the OS processes.

Checking the most open FD appear WLS Managed Servers and they are almost on the limit:

4076 376 /u04/Middleware/WLS12c/jdk/bin/java-server-Xms1024m-Xmx2048m-XX:PermSize=256m-XX:MaxPermSize=512m-Dweblogic.Name=WLS02

4063 32526 /u04/Middleware/WLS12c/jdk/bin/java-server-Xms1024m-Xmx2048m-XX:PermSize=256m-XX:MaxPermSize=512m-Dweblogic.Name=WLS01

Checking with lsof -p <pid> we see a lot of open jar files from war files, because we have several war files deployed.

Check:

$ ulimit -n
4096

Therefore the solution is to set a bigger soft & hard limit.

How to know OHS version

$ ./httpd.worker -v
./httpd.worker: error while loading shared libraries: libexpat.so.0: cannot open shared object file: No such file or directory

$ ps -fea | grep httpd

$ export ORACLE_HOME=/u04/Middleware/P_OHS12c/product

$ export LD_LIBRARY_PATH=/u04/Middleware/P_OHS12c/product/lib

$ cd /u04/Middleware/P_OHS12c/product/wlserver/../ohs/bin/

$ ./httpd.worker -v
Server version: Oracle-HTTP-Server/2.2.22 (Unix)
Server built:   Sep  3 2015 01:14:57
Server label:   APACHE_12.1.3.0.0_LINUX.X64_RELEASE

Sed cheat sheet

Sometimes we need to clean-up a file (ie: log prod file).

(or gsed for gnu-sed in macosx

* delete a match and backup of original file:

sed -i.bak '/<ConnectionEnv.cleanup, jconn=oracle.jdbc.driver.T4CConnection/d' ./infile

sed -i.bak '/INFO: true/d' ./infile

gsed -i.bak '/INFORMACIÓN: true> /d' ./infile


* delete two lines and the match string

gsed -i -e '/match1/,+2d'

* delete one line and the match string

gsed -i -e '/OPTIONS/,+1d' *uml*.puml

* execute more than one command in sed (use -e flag)

sed -i -e 's/File//g' -e 's/MINvac.pdb//g'

* recursive find and replace

find . -type f -print0 | xargs -0 sed -i 's/MYSQL_USER/MYSQL_ROOT_USER/g'

* no lookups by default

use: -E o -r ( -E, -r, --regexp-extended )