Hi, Tomcat's JNDI implementation does not support sharing for that matter even external connections. (This is in the FAQ by the way). If you want to share an object among multiple Tomcat instances via JNDI, you must use a JNDI provider that supports this.
Yoav Shapira http://www.yoavshapira.com >-----Original Message----- >From: John Smith [mailto:[EMAIL PROTECTED] >Sent: Sunday, December 12, 2004 1:12 AM >To: "Tomcat Users List" >Subject: JNDI object not shared among TC instances > >Hi, > > as, I understand things, the JNDI can be used to share an object among >different JVMs even from J2SE applications running on different machines. >Right? > > I need a relatively light object (that is why I am avoiding EJBs >altogether) which would simply: > 1._ poll a backend database at configurable periods, and if some data has >changed > 2._ update its internal state, which is then > 3._ administered to and updated in a number of independent tomcat >instances > > Well, I did the following exp. and repeated it even compiling TC 5.5.5 >from >source in case I had to check it, but before I start diving deeper into >what >I think might be the reason for this anomaly, I want to check that I don't >have a silly conf problem I haven't seen or there is something I am not >quite understanding here. > > Here is the method to my madness: > > 1._ I first downloaded TC's source code, 'built it' with ant, ran and >tested it. > 2._ Then I set up a number (3) of separate instances running from >independent JVMs using the same files as in the original, plain >installation, as describe in 1; by: > 2.1_ setting up three independent directories, <...> /tc00/, /tc02/, and >/tc04/ off the original installation > 2.2_ just copying /conf/ and /bin/ from the original installation and >dumping similar files on each dir described in 2.1 > 2.3_ changing then in each of the /conf/server.xml > 2.3.1_ the Server port="8005" > 2.3.2_ the non-SSL HTTP/1.1 Connector port="8080" > 2.3.3_ the AJP 1.3 Connector port="8009" (<- will need it for later >tinkering with Apache) >for all three independent instances, and > 2.4_ making sure that the same absolute directory was used in the appBase >attribute of the <Host name="localhost" . . . context > 2.5_ then, making sure that the same; > 2.5.1_ JAVA_HOME > 2.5.2_ CATALINA_HOME >but different > 2.5.3_ CATALINA_BASE >was set in the respective .../tcXX/bin/catalina.bat files (client wants me >to 'try' windows 'too'), pointing to the respective .../tcXX > 3._ I then run all three instances and tested every thing was OK and scan >log files for any errors, warnings, . . . > > Everything seemed to be working just fine! > >// - - - - - - - - - - - - - - - - - - - - - > > Then I used the following slimmed down classes from example code sections >in the jakarta JNDI howto, in order to illustrate my point. > > Both classes were placed in the original installation's >/common/classes/JNDITest/ directory > >// - - - - - - - - - - - - - - - - - - - - - >package JNDITest; > >public class JNDI00{ > private int bar = 0; > private long lCreatTime = System.currentTimeMillis(); > private String foo = "Default Foo, created at " + lCreatTime + ""; >// __ > public String getFoo() { return (this.foo); } > public void setFoo(String foo) { this.foo = foo; } >// __ > public int getBar() { return (this.bar); } > public void setBar(int bar) { this.bar = bar; } >// __ > public long getCreatTime() { return (lCreatTime); } > public void setCreatTime(long l){} >// __ >} > >// - - - - - - - - - - - - - - - - - - - - - >package JNDITest; > >import java.util.*; >import javax.naming.*; >import javax.naming.spi.*; > >public class JNDI00Factory implements ObjectFactory { > > public Object getObjectInstance(Object obj, Name name, Context nameCtx, >Hashtable environment) throws NamingException { > > JNDI00 JNDI_Obj = new JNDI00(); > > Reference ref = (Reference) obj; > Enumeration addrs = ref.getAll(); > while (addrs.hasMoreElements()) { > RefAddr addr = (RefAddr) addrs.nextElement(); > String aSNm = addr.getType(); > String value = (String) addr.getContent(); > if (aSNm.equals("foo")) { > JNDI_Obj.setFoo(value); > } else if (aSNm.equals("bar")) { > try { > JNDI_Obj.setBar(Integer.parseInt(value)); > } catch (NumberFormatException e) { > throw new NamingException("Invalid 'bar' value " + >value); > } > } > } > > return (JNDI_Obj); > } >} > >// - - - - - - - - - - - - - - - - - - - - - > then included for each TC instance in the <GlobalNamingResources> element >of $CATALINA_HOME/conf/server.xml > > <Resource name="JNDICtxt/JNDI00Factory" > auth="Container" > type="JNDITest.JNDI00" > factory="org.apache.naming.factory.BeanFactory" > bar="23"/> > > >// - - - - - - - - - - - - - - - - - - - - - > in $CATALINA_HOME/conf/ Catalina/localhost/ROOT.xml > > <ResourceLink name="jndiName" > global="JNDICtxt/JNDI00Factory" > type="JNDITest.JNDI00"/> > > >// - - - - - - - - - - - - - - - - - - - - - > and at the end of $CATALINA_HOME/webapps/ROOT/WEB-INF/web.xml > > <resource-env-ref> > <description>JNDICtxt JNDI00Factory Test</description> > <resource-env-ref-name>jndiName</resource-env-ref-name> > <resource-env-ref-type>JNDITest.JNDI00</resource-env-ref-type> > </resource-env-ref> > >// - - - - - - - - - - - - - - - - - - - - - > Then included right on /ROOT/index.jsp code segments looking like: > ><%@ page language="java" %> ><%@ page import="java.util.*" %> ><%@ page import="java.io.*" %> ><%@ page import="javax.naming.*" %> > ><%@ page import="JNDItest.*" %> > ><%@ page session="false" %> > ><%! >// __ > private Context initCtxt; > private Context envCtxt; > private JNDI00 JNDIObj; >// __ > public void jspInit(){ >// __ JNDI resources > String aBug = "<ul>"; >// __ > try{ > initCtxt = new InitialContext(); > envCtxt = (Context)initCtxt.lookup("java:comp/env"); >// __ > String aInitCtxt = initCtxt.toString(); > String aEnvCtxt = envCtxt.toString(); >// __ > aBug += "<li>initCtxt: " + aInitCtxt + "</li>"; > aBug += "<li>EnvCtxt: " + aEnvCtxt + "</li>"; >// __ >System.err.println(" initCtxt: |" + initCtxt + "|"); >System.err.println(" envCtxt: |" + envCtxt + "|"); >// __ >System.err.println(" (new JNDI00()): |" + (new JNDI00()) + "|"); >// __ > String aCtxtURL = "JNDICtxt/JNDI00Factory"; > aCtxtURL = "jndiName"; > > JNDIObj = (JNDI00)envCtxt.lookup(aCtxtURL); >System.err.println(" JNDIObj: |" + JNDIObj + "|"); > if(JNDIObj != null){ >System.err.println(" JNDIObj: |" + JNDIObj + "|"); >System.err.println(" JNDIObj.getBar(): |" + (new >Integer(JNDIObj.getBar())).toString() + "|"); >System.err.println(" JNDIObj.getCreatTime(): |" + JNDIObj.getCreatTime() + >"|"); >System.err.println(" JNDIObj.getFoo(): |" + JNDIObj.getFoo() + "|"); >// __ > aBug += "<li>JNDIObj: |" + JNDIObj.toString() + "|</li>"; > aBug += "<li>JNDIObj.getBar(): |" + (new >Integer(JNDIObj.getBar())).toString() + "|</li>"; > aBug += "<li>JNDIObj.getCreatTime(): |" + JNDIObj.getCreatTime() + >"|</li>"; > aBug += "<li>JNDIObj.getFoo(): |" + JNDIObj.getFoo() + "|</li>"; > } >// __ > aBug += "</ul>"; > }catch(NamingException NmX){ NmX.printStackTrace(); } >// __ > }// jspInit() >// __ > public void JspDestroy(){} >%> > ><% >// __ Response Headers > response.setHeader("Cache-Control", "no-cache"); > response.setHeader("Pragma", "no-cache"); > response.setDateHeader("Expires", 0); >// __ >%> > >// - - - - - - - - - - - - - - - - - - - - - >and inside the actual page just after <body> > ><%=aBug%> > >// - - - - - - - - - - - - - - - - - - - - - > > You will see each TC instance has its own instances of: > * javax.naming.InitialContext > * org.apache.naming.NamingContext > * JNDITest.JNDI00 > > > What is it I am doing wrong here? > > How could you achieve what I want, namely, read (kind of a singleton >object >from different TOmcat instances? > > "Any help would be appreciated" > > > >--------------------------------------------------------------------- >To unsubscribe, e-mail: [EMAIL PROTECTED] >For additional commands, e-mail: [EMAIL PROTECTED] This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. 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