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Created by Dr. Xi on June 17, 2012 13:14:25
Last update: June 17, 2012 13:14:25
Link to official Java networking properties page: http://docs.oracle.com/javase/7/docs/technotes/guides/net/properties.html
http.keepAlive (default: true)
Indicates if keep alive (persistent) connections should be supported. Persistent connections improve performance by allowing the underlying socket connection be reused for multiple http requests.
The default is true and thus persistent connections will be used with http 1.1 servers. Set to 'false' to disable the use of persistent connections.
http.maxConnections (default: 5)
If HTTP keep-alive is enabled, this value is the number of idle connections that will be simultaneously kept alive, per-destination.
Created by nogeek on November 27, 2011 12:24:27
Last update: November 27, 2011 12:24:27
There is no XSLT 2.0 support in the JDK as of 7.0. According to Stackoverflow , there are three Java packages that support XSLT 2.0: Saxon IBM WebSphere XML Feature Pack Oracle XDK There are no known support for XSLT in browsers. According to Wikipedia : XSLT is developed by the World Wide Web Consortium (W3C). The most recent version is XSLT 2.0, which reached W3C recommendation status on 23 January 2007. As of 2010, however, XSLT 1.0 is still widely used, as there are no products that support XSLT 2.0 running in the browser, nor on some important server environments such as LAMP. Expressions like this:
format-date(xs:date('1999-12-31'), '[D01] [MNn] ... where format-date is a XSLT 2.0 function and date is a XPath 2.0 constructor...
Created by Fang on September 07, 2009 20:44:15
Last update: November 03, 2011 14:43:19
Step 1: Repackage a web app as EAR A Java EE application is a multimodule Maven project. At the very least you'll need to package a WAR and an EAR. To get started, I'll simply re-package the simple webapp as an EAR. Create a directory named javaee-app Copy the webapp from here to javaee-app . Rename struts1app to webapp . Create pom.xml under javaee-app :
<project> <modelVersion>4.0.0</modelVersion>... Create a directory named ear under javaee-app . Create pom.xml under ear : <project> <modelVersion>4.0.0</modelVersion>... Modify pom.xml in the webapp directory so that it looks like this: <project> <modelVersion>4.0.0</modelVersion> ... Build with " mvn package " in the javaee-app directory. You can see that ear-1.0.ear is successfully generated in javaee-app/ear/target . Maven successfully resolves dependencies between the sub-projects....
Created by Fang on October 22, 2011 20:43:31
Last update: October 22, 2011 20:45:13
The only explanation of why some Java EE API classes are stripped off methods implementations I can find is this JBos forum post: What's the cause of this exception: java.lang.ClassFormatError: Absent Code? which also provides some workarounds for these crippled API classes. The explanation offered was: When one compiles, they want to run as well. By the way, we have been promoting full set of Java EE APIs which can only be used for compilation - they are stripped off method details. That way, user can't take those artifacts and try to use it in runtime. Honestly, I don't see any logic in those statements. This is the only place any such explanation is offered. Yes only from this JBos forum post! There's no public...
Created by alfa on May 20, 2011 15:54:23
Last update: May 20, 2011 15:54:23
From Oracle : The simplest and most reliable way to achieve short garbage collection times over the lifetime of a production server is to use a fixed heap size with the default collector and the parallel young generation collector, restricting the new generation size to at most one third of the overall heap. The following example JVM settings are recommended for most engine tier servers:
-server -XX:MaxPermSize=128m -XX:+UseParNewGC -XX:... If the engine tier server enables caching for call state data, the example settings are: -server -XX:MaxPermSize=128m -XX:+UseParNewGC -XX:... For replica servers, use the example settings: -server -XX:MaxPermSize=128m -XX:+UseParNewGC -XX:... The above options have the following effect: -XX:+UseTLAB - Uses thread-local object allocation blocks. This improves concurrency by reducing contention on the shared heap lock. -XX:+UseParNewGC...
Created by meiu on February 09, 2010 03:26:14
Last update: March 31, 2011 09:00:19
Simple JDBC code for Oracle.
import java.sql.*;
public class JDBCHelloWo...
Created by voodoo on November 25, 2010 00:03:53
Last update: November 25, 2010 00:03:53
It seems that the JDBC standard way to create a BLOB is to call Connection.createBlob . However, this does not work for PostgreSQL (as of version 9.0-801 jdbc4):
Exception in thread "main" org.postgresql.util.PSQ...
The workaround is to call a PostgreSQL function to create the Blob, then use JDBC to update it:
Connection conn = jdbcTemplate.getDataSource().get...
Oracle Note: the Oracle way function to create an empty BLOB is EMPTY_BLOB() .
stmt.execute ("INSERT INTO my_blob_table VALUES ('...
Created by meiu on July 22, 2010 20:16:59
Last update: July 22, 2010 20:17:28
By this thread on OTN, JRockit mission control and JRockit real time are exactly the same!
JRockit Mission Control x JRockit Real Time
But Oracle is offering downloads with two separate links with no explanation what so ever?!
Created by Dr. Xi on September 20, 2009 16:52:19
Last update: March 22, 2010 01:28:49
When I assemble a session bean without the proprietary deployment descriptor ( orion-ejb-jar.xml ), OC4J generates one like this (as can be seen from the OC4J management console):
<?xml version="1.0" encoding="utf-8"?>
<ori...
So I use this code to lookup the EJB:
import javax.naming.Context;
import javax.namin...
OC4J throws ClassCastException :
java.lang.ClassCastException: com.evermind[Oracle ...
The JNDI browser (OC4J container home -> Administration -> JNDI browser) shows that the name simpleEjb_SimpleBeanLocal is bound to: com.evermind.server.ejb.StatelessSessionDefaultLocalHomeImpl
Solution:
Change the local name in the OC4J generated orion-ejb-jar.xml to simpleEjb_SimpleBeanLocal2 and put it in the EJB package. Redeploy.
The JNDI browser shows that simpleEjb_SimpleBeanLocal is still bound to com.evermind.server.ejb.StatelessSessionDefaultLocalHomeImpl . But simpleEjb_SimpleBeanLocal2 is bound to the right proxy: SimpleBean_LocalProxy_5f4b5e5 .
Created by Dr. Xi on February 12, 2010 22:39:15
Last update: February 12, 2010 22:39:15
When you start Tomcat for the first time, you may get the "port 8080 is already in use" error. Indeed, port 8080 is commonly used by a lot of development servers by default (Oracle XE for another example). Luckily, it's quite easy to ask Tomcat to use a different port. I use port 8086, which is a natural next step and superior to 8080.
Simply edit $CATALINA_BASE/conf/server.xml and change 8080 to 8086:
<!-- A "Connector" represents an endpoint by w...
If you have not configured Tomcat 6 for multiple instances by setting a CATALINA_BASE directory, then $CATALINA_BASE will be set to the value of $CATALINA_HOME , the directory into which you have installed Tomcat 6.