Apache Tomcat Version 4.0.6 =========================== Release Notes ============= $Id: RELEASE-NOTES-4.0.6.txt,v 1.1.2.1 2002/10/08 13:34:54 remm Exp $ ============ INTRODUCTION: ============ This document describes the changes that have been made in the current release candidate release of Apache Tomcat, relative to the previous release. The release notes for all prior releases of Tomcat 4.0 are also included, for your reference. Bug reports should be entered at the bug reporting system for Jakarta projects at: http://nagoya.apache.org/bugzilla/ Please report bugs and feature requests under product name "Tomcat 4". ============ NEW FEATURES: ============ -------------------- General New Features: -------------------- ***** Please note the revised documentation below related to ***** ***** using XML parsers with Tomcat 4.0 based applications. ***** [F] Coyote: Upgrade to latest version. --------------------- Catalina New Features: --------------------- ------------------- Jasper New Features: ------------------- -------------------- Webapps New Features: -------------------- ========================== BUG FIXES AND IMPROVEMENTS: ========================== ------------------ Generic Bug Fixes: ------------------ ------------------ Catalina Bug Fixes: ------------------ [F] InvokerServlet: Improve class filter to prevent invocation of internal Catalina servlets. ---------------- Jasper Bug Fixes: ---------------- ----------------- Webapps Bug Fixes: ----------------- ---------------------- Bugzilla Bugs Resolved: ---------------------- ============================ KNOWN ISSUES IN THIS RELEASE: ============================ * Tomcat 4.0 and JNI Based Applications * Tomcat 4.0 Standard APIs Available * Tomcat 4.0 and XML Parsers * Web application reloading and static fields in shared libraries * JAVAC leaking memory * Linux and Sun JDK 1.2.x - 1.3.x * Jasper and Jikes * Tomcat 4.0 and Apache Cocoon 2.0 * Enabling SSI and CGI Support * Tomcat 4.0 and Sun JDK 1.4 beta 3 ------------------------------------- Tomcat 4.0 and JNI Based Applications: ------------------------------------- Applications that require native libraries must ensure that the libraries have been loaded prior to use. Typically, this is done with a call like: static { System.loadLibrary("path-to-library-file"); } in some class. However, the application must also ensure that the library is not loaded more than once. If the above code were placed in a class inside the web application (i.e. under /WEB-INF/classes or /WEB-INF/lib), and the application were reloaded, the loadLibrary() call would be attempted a second time. To avoid this problem, place classes that load native libraries outside of the web application, and ensure that the loadLibrary() call is executed only once during the lifetime of a particular JVM. ---------------------------------- Tomcat 4.0 Standard APIs Available: ---------------------------------- A standard installation of Tomcat 4 makes all of the following APIs available for use by web applications (by placing them in "common/lib" or "lib"): * activation.jar (Java Activation Framework) * jdbc2_0-stdext.jar (JDBC 2.0 Optional Package, javax.sql.*) * jndi.jar (JNDI 1.2 base API classes) * jta-spec1_0_1 (Java Transacation APIs) * mail.jar (JavaMail 1.2) * servlet.jar (Servlet 2.3 and JSP 1.2 APIs) * tyrex-0.9.7.0.jar (Tyrex XA-compatible data source from tyrex.exolab.org) * xerces.jar (Xerces 1.4.3) You can make additional APIs available to all of your web applications by putting unpacked classes into a "classes" directory (not created by default), or by placing them in JAR files in the "lib" directory. -------------------------- Tomcat 4.0 and XML Parsers: -------------------------- As described above, Tomcat 4.0 makes an XML parser (and many other standard APIs) available to web applications. This parser is also used internally to parse web.xml files and the server.xml configuration file. If you wish, you may replace the "xerces.jar" file in "common/lib" with another XML parser, as long as it is compatible with the JAXP/1.1 APIs. --------------------------------------------------------------- Web application reloading and static fields in shared libraries: --------------------------------------------------------------- Some shared libraries (many are part of the JDK) keep references to objects instantiated by the web application. To avoid class loading related problems (ClassCastExceptions, messages indicating that the classloader is stopped, ...), the shared libraries state should be reinitialized. Something which could help is to avoid putting classes which would be referenced by a shared static field in the web application classloader, and put them in the shared classloader instead (the JARs should be put in the "lib" folder, and classes should be put in the "classes" folder). -------------------- JAVAC leaking memory: -------------------- The Java compiler leaks memory each time a class is compiled. Web applications containing hundreds of JSP files may as a result trigger out of memory errors once a significant number of pages have been accessed. The memory can only be freed by stopping Tomcat and then restarting it. The JSP command line compiler (JSPC) can also be used to precompile the JSPs. ------------------------------- Linux and Sun JDK 1.2.x - 1.3.x: ------------------------------- Virtual machine crashes can be experienced when using certain combinations of kernel / glibc under Linux with Sun Hotspot 1.2 to 1.3. The crashes were reported to occur mostly on startup. Sun JDK 1.4 does not exhibit the problems, and neither does IBM JDK for Linux. The problems can be fixed by reducing the default stack size. At bash shell, do "ulimit -s 2048"; use "limit stacksize 2048" for tcsh. GLIBC 2.2 / Linux 2.4 users should also define an environment variable: export LD_ASSUME_KERNEL=2.2.5 ---------------- Jasper and Jikes: ---------------- Jikes can be used with the Jasper JSP page compiler, but the runtime classes JAR of the JDK or JRE (depending on what is installed on the computer) must be added to the system classpath. This can be achieved by editing the main catalina script, and adding the rt.jar file: On Windows: line 71 of %CATALINA_HOME%\bin\catalina.bat, change set CP=%CATALINA_HOME%\bin\bootstrap.jar;%JAVA_HOME%\lib\tools.jar to set CP=%JAVA_HOME%\jre\lib\rt.jar;%CATALINA_HOME%\bin\bootstrap.jar;%JAVA_HOME%\lib\tools.jar On Unix or Unix-like OSes: line 89 of $CATALINA_HOME/bin/catalina.sh, change CP="$CATALINA_HOME/bin/bootstrap.jar" to CP="$JAVA_HOME/jre/lib/rt.jar:$CATALINA_HOME/bin/bootstrap.jar" -------------------------------- Tomcat 4.0 and Apache Cocoon 2.0: -------------------------------- For optimal performance with Apache Cocoon 2.0, it is recommended to use the HTTP/1.0 connector. ---------------------------- Enabling SSI and CGI Support: ---------------------------- Having CGI and SSI available to web applications created security problems when using a security manager (as a malicious web application could use them to sidestep the security manager access control). In Tomcat 4.0, they have been disabled by default, as our goal is to provide a fully secure default configuration. However, CGI and SSI remain available. On Windows: * rename the file %CATALINA_HOME%\server\lib\servlets-cgi.renametojar to %CATALINA_HOME%\server\lib\servlets-cgi.jar. * rename the file %CATALINA_HOME%\server\lib\servlets-ssi.renametojar to %CATALINA_HOME%\server\lib\servlets-ssi.jar. * in %CATALINA_HOME%\conf\web.xml, uncomment the servlet declarations starting line 165 and 213, as well as the associated servlet mappings line 265 and 274. Alternately, these servlet declarations and mappings can be added to your web application deployment descriptor. On Unix: * rename the file $CATALINA_HOME/server/lib/servlets-cgi.renametojar to $CATALINA_HOME/server/lib/servlets-cgi.jar. * rename the file $CATALINA_HOME/server/lib/servlets-ssi.renametojar to $CATALINA_HOME/server/lib/servlets-ssi.jar. * in $CATALINA_HOME/conf/web.xml, uncomment the servlet declarations starting line 165 and 213, as well as the associated servlet mappings line 265 and 274. Alternately, these servlet declarations and mappings can be added to your web application deployment descriptor. --------------------------------- Tomcat 4.0 and Sun JDK 1.4 beta 3: --------------------------------- Some unpredictable classloading behavior has been reported when Tomcat is used with Sun JDK 1.4 beta 3. The problem has been fixed with Sun JDK 1.4 Realease Candidate or later.