wlkid 0600001KH8 1,584 Views
Android's task manager (long pressing HOME key) will list both the recently closed Application(s) and Running Application(s), thus it obscure the traditional border, which is clear to both the user and developer in past time, between this two concepts/semantics, and, hence, put much more effort/confusion/complexity on developers to adapt to this new model, and the end users will be confused/mislead by this new model too - thought the app closed as usual (the user thought), but due this new model, the app still kept the data (the app's developer designed to follow Android's way) the user entered which the user do not want it be viewed at late time for some reason, or due to the developers design, the data did not persisted as the application seems to be "closed", but at late time, the device crashed and so the data lost, or due to developers on purpose design to do some user unwanted background jobs when the application "closed"!
It changed the semantics of closing application which adopted for decades, and make things much more unnecessary complex and put the user in front of PRIVACY LEAKING, DATA LOST, UNWANTED and UNSTOPPABLE BEHAVIOUS/APPLICATIONS, and LOST CONTROL!
I DO NOT LIKE THIS DESIGN REALLY!
the difference between normal git repo and bare git
The code doesn't tell the whole story
it's hard work and if you don't ask the right questions, you won't get the right answers.
you don't know what you don't know
What is software architecture? http://www.codingthearchitecture.com/pages/what.html
How do you define software architecture? http://www.codingthearchitecture.com/pages/define.html
for struts2 2.1.8
it seems that there must have class attribute set and optionally specify which packages to scan, only after that the url mapping will work, failed with above and occupied much time, the reason is just a guess, not verified yet
OS A can connect to both intranet and internet
OS B can connect to internet only
OS A is Windows XP
install OpenSSH for Windows on OS A and start the OpenSSHd service that comes with it
on OS B
ssh -D 6507 username@OsA -f 'ping -t somehost' > /dev/null
above command will let ssh tunnel run on OS B in background, and, thus you can continue your work in console on OS B
now OS B has a socks server on port 6507
you can set the proxy in browser to localhost:6507 so you can connect to servers run in intranet
if use putty on OS B, then follow settings as below screenshot
in addition, with SocksCap, you can tunnel the applications you desired only, or tunnel the applications that do not support proxy
PS: proxifier support both auto and manual tunnel applications (for example, let TortoiseSVN to connect to server in intranet)
PPS: to securely transfer files from and to remote, WinSCP which like the scp/sftp command is available on Windows platform
PPPS: OS A and OS B can on same physical machine (with the help of VirtualBox or VMware) - this is for the scenario that VPN software works on specified OS only, but unfortunately, which is not your favorite OS
wlkid 0600001KH8 2,676 Views
jmap -histo <pid>
(to connect to running process and print histogram of java object heap
jmap -dump:<dump-options> <pid>
(to connect to running process and dump java heap)
format=b binary default
file=<file> dump heap to <file>
Example: jmap -dump:format=b,file=heap.bin
or, run jconsole, select MBeans -> com.sun.management -> HotSpotDiagnostic -> Operations -> dumpHeap, fill p0 as deisred dump file path (if using Eclipse Mempry Analyzer to analyze it, the file extension is better to be .hprof), click dumpHeap button to dump it.
or, generate it using Eclipse Memory Analyzer directly
or, let jvm generate it when out of memory: add -XX:+HeapDumpOnOutOfMemoryError or -XX:+HeapDumpOnCtrlBreak, more details here: http://wiki.eclipse.org/index.php/MemoryAnalyzer#Getting_a_Heap_Dump
ps: dump file can be parsed by Eclipse Memory Analyzer
Finding Memory Leaks
Start by running the leak report to automatically check for memory leaks.
This blog details How to Find a Leaking Workbench Window.
The Memory Analyzer grew up at SAP. Back then, Krum blogged about Finding Memory Leaks with SAP Memory Analyzer. The content is still relevant! Analyzing Java Collection Usage
Check out Krum’s blog about Analyzing Java Collections Usage with Memory Analyzer. Also, Memory for Nothing looks unused collections and the memory kept alive.
Perm Space Issus
good starting point is the blog The Unknown Generation: Perm by Andreas.
Also, Vedran has blogged some hints how to address Perm Space Issues.