Java Applet in iframe fails to load in Mac Safari

For a Facebook iframe app, we load a file browser Java applet. This works fine in all major browsers on PC, and Firefox on the Mac. It also loads fine outside of an iframe in Safari on the Mac.

However, as soon as the page is called from within an iframe in Safari/Mac, the applet will not load. We do get the signed applet permission pop-up, but after that the loading just spins until it times out.

I have tested this in an iframe outside of Facebook, as well as within, so I know it is not a Facebook issue. Have also made sure Java is enabled and up-to-date in Safari, and observed no relevant error messages in the console.

Has anyone else run into this issue, and if so, is there a solution or workaround that can be implemented?

UPDATE: Output from Java console below. Always hangs at the same place on the liveconnect call, no error thrown.

Java Plug-in 1.6.0_22
Using JRE version 1.6.0_22-b04-307-10M3261 Java HotSpot(TM) Client VM
User home directory = /Users/user
Java Plug-in 1.6.0_22
Using JRE version 1.6.0_22-b04-307-10M3261 Java HotSpot(TM) Client VM
User home directory = /Users/user
network: Loading user-defined proxy configuration…
network: Done.
network: Loading proxy configuration from Netscape Navigator…
network: Done.
network: Loading direct proxy configuration…
network: Done.
network: Proxy Configuration: No proxy
basic: Referencing classloader: sun.plugin.ClassLoaderInfo@da90c, refcount=1
basic: Added progress listener: sun.plugin.util.GrayBoxPainter$GrayBoxProgressListener@1797795
basic: Loading applet…
basic: Initializing applet…
basic: Starting applet…
basic: completed perf rollup
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Connecting http://[server_address_removed]/testutility10_21_2009_10_27_45.jar with proxy=DIRECT
network: Connecting socket://[server_address_removed]:80 with proxy=DIRECT
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Connecting http://[server_address_removed]/testutility10_21_2009_10_27_45.jar with proxy=DIRECT
network: Downloading resource: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar
Content-Length: 3,686
Content-Encoding: null
security: Blacklist revocation check is enabled
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Connecting http://[server_address_removed]/testutility10_21_2009_10_27_45.jar with proxy=DIRECT
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/testutility10_21_2009_10_27_45.jar, version: null]
BaseApplet:init-complete
applet:start
invoking startup callback testAppletInitialized
liveconnect: JSObject::call: name=open
basic: Referencing classloader: sun.plugin.ClassLoaderInfo@602b6b, refcount=1
basic: Added progress listener: sun.plugin.util.GrayBoxPainter$GrayBoxProgressListener@18a6e6e
basic: Loading applet…
basic: Initializing applet…
basic: Starting applet…
basic: completed perf rollup
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Connecting http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar with proxy=DIRECT
network: Connecting socket://[server_address_removed]:80 with proxy=DIRECT
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Connecting http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar with proxy=DIRECT
network: Downloading resource: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar
Content-Length: 33,019
Content-Encoding: null
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
security: Loading Root CA certificates from /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/lib/security/cacerts
security: Loaded Root CA certificates from /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/lib/security/cacerts
security: Loading certificates from Deployment session certificate store
security: Loaded certificates from Deployment session certificate store
security: Loading Root CA certificates from from keychain
security: Loaded Root CA certificates from from keychain
security: Validate the certificate chain using CertPath API
security: Obtain certificate collection in Root CA certificate store
security: Obtain certificate collection in Root CA certificate store
security: Obtain certificate collection in Root CA certificate store
security: jpicertstore.cert.getkeystore
security: No timestamping info available
security: Cannot find jurisdiction list file
security: The CRL support is disabled
security: The OCSP support is disabled
security: This OCSP End Entity validation is disabled
security: Checking if certificate is in Deployment denied certificate store
security: Checking if certificate is in Deployment permanent certificate store
security: Checking if certificate is in Deployment session certificate store
security: Creating MacOSXTrust
security: Evaluating MacOSXTrust
security: MacOSXTrust: cert chain is valid, no explict intent
security: MacOSXTrust: cert chain is valid, keychain explicity requested user confirmation
security: Evaluating trust of site: [server_address_removed]
security: Did not find a trusted site record for: http://[server_address_removed]<ab7662bf>
security: Showing MacOSXTrustSiteDialog
security: User permitted app to continue with priviledges
security: MacOSXTrustUI.evaluateTrustAfterShow: returning GrantThisSession
security: User has granted the privileges to the code for this session only
security: Adding certificate in Deployment session certificate store
security: Added certificate in Deployment session certificate store
security: Saving certificates in Deployment session certificate store
security: Saved certificates in Deployment session certificate store
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Connecting http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar with proxy=DIRECT
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
network: Cache entry not found [url: http://[server_address_removed]/fileutility10_21_2009_10_27_45.jar, version: null]
calling workaround: javascript:testAppletInitialized("1.6.0_22");BaseApplet:init-complete
SingleFileServer23196574: server at http://127.0.0.1:3145
SingleFileServer23196574: server running
XMLSocketServer18107298:server at xmlsocket://127.0.0.1:7711
XMLSocketServer18107298:policy <cross-domain-policy><allow-access-from domain='[server_address_removed]' secure='false' to-ports='7711' /></cross-domain-policy>
applet:init-complete
XMLSocketServer18107298:running
applet:start
SingleFileServer23196574: now serving certificate e848b62e2782e2cef20fe2d075d9e633 at http://127.0.0.1:3145/certificate1290016856751
invoking startup callback
calling workaround: javascript:appletInitialized("http://127.0.0.1:3145","xmlsocket://127.0.0.1:7711","http://127.0.0.1:3145/certificate1290016856751");running on Mac OS X
applet:start-complete
liveconnect: JSObject::call: name开发者_StackOverflow=open

UPDATE: the solution below doesn't work consistently; in equal environments (Safari version, OS version, all settings the same), this only has worked on 1 of 4 Macs I tested on. Still looking for a consistent solution.

We were able to resolve this by modifying the Java Preferences in Mac OS:

1. Open Java Preferences (Applications > Utilities > Java Preferences)
2. On the General tab, change the default "Within the browser process" to "In their own process"
3. Make sure to empty the cache when restarting Safari.

Mac version: 10.6.5; Safari version: 5.0.2 ; Java version: 1.6.0_22-604-307

I still do not know the cause but I have found a workaround that works for us. What I accidently discovered was if you reload the applet frame it will load the applet the second time. One catch was if you did it too fast it would not work so I added setTimeout to it with a one second delay. This seems to work for us.

if ((navigator.platform.toUpperCase().indexOf("MAC") != -1) && (navigator.vendor.toUpperCase().indexOf("APPLE") != -1)) { 
 setTimeout("ReloadImageFrame('028-2007-009844', '', " + currentAppID + ")", 1000); }