If you ever need to search and replace strings throughout a bunch of files here’s a neat, somewhat alternative, way to do it.
for file in `ls **/*.txt`;do perl -pi -w -e ’s/SEARCH_FOR_THIS/REPLACE_WITH_THIS/g;’ $file; done
The nested ‘perl’ command can work kind of like ’sed’. Here are what the arguments being passed in mean:
-e means execute the following line of code.
-i means edit in-place
-w write warnings
-p loop
OK – I admit it – my IDE and tools make me weak in many ways. I was just having the hardest time getting my maven-managed project to run from a basic “java my.class.ClassName” command line invocation. Why? Because the freaking classpath is a million miles away from being a concern to me anymore. So, jog the memory and immediately remember the -cp ( or -classpath ) option. Also remember that I cannot specify a directory if I want to include all of the jars in that directory ( specifying a directory in the classpath will only load exploded .class files! ).
What I’ve got before me is a target/lib directory full of all of my maven2-managed dependencies. I need to add each jar file explicitly into the classpath – barf!
Well, here’s a handy little shell script which will build that string for you:
for file in `ls lib`; do echo -n ‘lib/’ >> classpath.txt;echo -n $file >> classpath.txt;echo -n ‘:’ >> classpath.txt;done
Awesome – so just open the classpath.txt file and use that big ‘ol path however you want to. Windows users would use a semi-colon instead of a colon above. Also, remember that you need to specify the classpath option prior to the name of the class to run – otherwise the classpath is ignored ( as it is assumed to be an argument to the program and not a jvm option ).
