[kaffe] Running Tomcat 5.0

[Rei Odaira]

Fernando Lozano wrote:
> Having read many reports on the archieve of success running Tomcat under 
> Kaffe, I decided to try myself using Tomcat 5.0.28. Although many JSP 
> pages and Servlets do run ok (icluding the Tomcat Manager and most 
> samples) many applications, including some examples and the Tomcat 
> Administrator fail with the following exception
> 
> java.lang.IllegalStateException: Zip file already closed: 
> /d/local/jakarta-tomcat-5.0.28/common/lib/commons-pool-1.2.jar
> 
> Any idea on how to workaround this, or should I fill a bug report? And 
> the bug report should go to Kaffe or Jakarta?

I have just found the cause of the problem.

org.apache.jasper.compiler.TldLocationsCache#scanJar() opens
commons-pool-1.2.jar, reads some entries, and finally closes it
when redeployMode == true, as shown below.

##################################################
    private void scanJar(JarURLConnection conn, boolean ignore)
                throws JasperException {

        JarFile jarFile = null;
        String resourcePath = conn.getJarFileURL().toString();
        try {
            if (redeployMode) {
                conn.setUseCaches(false);
            }
            jarFile = conn.getJarFile();
            Enumeration entries = jarFile.entries();
...<snip>...

        } finally {
            if (redeployMode) {
                // if in redeploy mode, always close the jar
                if (jarFile != null) {
                    try {
                        jarFile.close();
                    } catch (Throwable t) {
                        // ignore
                    }
                }
            }
        }
    }
##################################################

Since a JarURLConnection can internally cache JarFile objects,
scanJar() first disables the caching by calling setUseCaches(false)
when it wants to close the JarFile later.  However,
gnu.java.net.protocol.jar.Connection, which extends JarURLConnection,
does not check for the useCaches flag when it opens a connection.
Therefore, the unintendedly cached JarFile object becomes stale
after it gets closed by scanJar().  If Tomcat re-opens
commons-pool-1.2.jar through JarURLConnection, it will get
the already closed JarFile object.

The attached patch fixes this problem.

Rei
-------------- next part --------------
Index: libraries/javalib/gnu/java/net/protocol/jar/Connection.java
===================================================================
RCS file: /cvs/kaffe/kaffe/libraries/javalib/gnu/java/net/protocol/jar/Connection.java,v
retrieving revision 1.8
diff -a -u -r1.8 Connection.java
--- libraries/javalib/gnu/java/net/protocol/jar/Connection.java	8 Mar 2005 21:03:53 -0000	1.8
+++ libraries/javalib/gnu/java/net/protocol/jar/Connection.java	9 Apr 2005 15:22:59 -0000
@@ -69,13 +69,18 @@
     private static Hashtable cache = new Hashtable();
     private static final int READBUFSIZE = 4*1024;
     
-    public static synchronized JarFile get (URL url) throws IOException
+    public static synchronized JarFile get (URL url, boolean use_caches) throws IOException
     {
-      JarFile jf = (JarFile) cache.get (url);
+      JarFile jf;
+
+      if (use_caches)
+	{
+	  jf = (JarFile) cache.get (url);
+
+	  if (jf != null)
+	    return jf;
+	}
 
-      if (jf != null)
-        return jf;
-      
       if ("file".equals (url.getProtocol()))
 	{
 	  File f = new File (url.getFile());
@@ -101,7 +106,8 @@
 			    ZipFile.OPEN_READ | ZipFile.OPEN_DELETE);
 	}
           
-      cache.put (url, jf);
+      if (use_caches)
+	cache.put (url, jf);
       
       return jf;
     }
@@ -120,7 +126,7 @@
       return;
 
     jar_url = getJarFileURL();
-    jar_file = JarFileCache.get (jar_url);
+    jar_file = JarFileCache.get (jar_url, useCaches);
     String entry_name = getEntryName();
     
     if (entry_name != null