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If you want to extract from the nth token to the end of the line, following is how you can do that with awk:
Given a source file with the following:
line1 -- 01 0011 1
line2 -- 01 0011 2
line3 -- 01 0011 3
line4 -- 01 0011 4
line5 -- 01 0011 5
line6 -- 01 0011 6
line7 -- 01 0011 7
line8 -- 01 0011 8
line9 -- 01 0011 9
line10 -- 01 0011 By default (Java 1.6 or greater), the JVM will output, at most, 1024 lines of the stack trace.
In the situation where you have some recursion problem or some infinite loop that results in a stack overflow error you will need to increase this value with a JVM option to see the origin of your crash.
To do so, add the following option to the java command
$ java -XX:MaxJavaStackTraceDepth=-1 -jar some.jar some.package.Class etc, etc,-1 indicates no limit. Any → Continue reading “JVM Option for Increasing the Default Number of Lines in the StackTrace”
In some instances you cannot reproduce a failure or condition running a test in an IDE that manifests itself when you run it on your build server or via maven on the command line.
In that case, it is very helpful to be able to remotely attach your IDE to the running maven process and then step through the code.
To do so you will need to:
Execute maven on the command line as follows (adding any additional -D args → Continue reading “Debugging Maven Tests by Connecting an IDE to the Maven JVM”
If you are attempting to use jmap or another Java memory analysis tool to connect to a running JVM to generate a heap dump, even when running jmap as the same user as that of the running process, and encounter the following error:
Attaching to process ID 2712, please wait...
Error attaching to process: sun.jvm.hotspot.debugger.DebuggerException: Can't attach to the processFollowing is the (likely) solution to your problem.
It is likely that the ptrace_scope setting for your system is set → Continue reading “Error attaching to process: sun.jvm.hotspot.debugger.DebuggerException: Can’t attach to the process [SOLVED]”
For whatever reason, Ubuntu 14.04 does not seem to come with a firewall.
There are however two packages which provide, both a firewall and a handy GUI front-end for it. UncomplicatedFireWall is the main package (ufw) and the GUI is gufw.
To install:
apt-get install gufwThis will install the front-end and the dependent packages
To turn it on:
ufw enableThe default is to block all incoming traffic.
To update and add your own firewall rules and allow incoming → Continue reading “Firewall for Ubuntu 14.04 LTS”
By now, everyone is aware of the Stagefright vulnerability in Android. It isn’t as much the name of the vulnerability but a media player library used in Android.
It seems that one of the ways to remediate the vulnerability is to configure your text messaging application to NOT auto-retrieve Multimedia messages (MMS). On my phone that is under the Advanced Settings, “Auto-retrieve Automatically retrieve messages”.
The other thing that I did was disable Google Hangouts. I don’t use it on → Continue reading “Possible Remediation for Stagefright Android Vulnerability”
The following is a one-liner for generating a random string of a fixed size in bash, where the possible characters to use in the string are any digit, letter, and a newline.
By adding the newline, you are fairly sure to prevent getting one long line of text.
< /dev/urandom tr -dc "[:digit:][:alpha:][\n]" | head -c1000 file.outIf you are using Chef and Test Kitchen to test your cookbooks you may have need to connect to the Test Kitchen VM in some other fashion other than $ kitchen login instance-name.
To do so:
Do a $ kitchen list to see the running vms
kitchen list
Instance Driver Provisioner Verifier Transport Last Action
default-centos-66 Vagrant ChefSolo Busser Ssh ConvergedThen look in the .kitchen directory from where you ran your $ kitchen command and look for the corresponding → Continue reading “Connecting To a Test Kitchen Instance Via SFTP, SSH, or SCP”
By default maven sets the compiler version for you. Of course, you can always set it in the pom, but there are cases where you cannot modify the pom, and/or you might want to test compilation and tests with different versions of java.
Following are the specific arguments to pass the compiler version to maven from the command line:
mvn clean install -Dmaven.compiler.source=1.7 -Dmaven.compiler.target=1.7From Joshua Bloch’s Effective Java, 2nd Edition.
A good read for any Java programmer.→ Continue reading “An Excellent Article on finalize in Java”