Subduing CLASSPATH

# !python
"""
SetClasspath.pybyBruceEckel,2006www.MindView.net
Permissiongrantedforfreeuseanddistributionaslongasthisnoticeismaintained.

Warning!ThisprogrammodifiestheWindowsRegistry!Useatyourownrisk.

Withnoarguments:
Iftherearejarfilesinthecurrentdirectory,eachoneisaddedtotheCLASSPATH.
Iftherearenojarfiles,thecurrentdirectoryisaddedtotheCLASSPATH.

Witharguments:
Eachargumentmustbeajarfilename.EachargumentisaddedtotheCLASSPATH.

DuplicateCLASSPATHentriesandnonexistentpathsareremoved.

IrecommendcreatingC:jarsdirectory,andaddingthisprogramtothatdirectory.
Wheneveryouneedtoaddanewjar,throwitinC:jarsanddouble-clickthisprogram.
Thatway,ifyouneedthesamesetofjarsonanothermachine,justcopythe
directoryandrunthisprogram.

It'salsousefultocreateabatch/cmdfiletorunthisprogram,andtoplace
thatfileinyourWindowsPATH.Thenyoucanruntheprogramfromanydirectory.
Thebatchfilemightlooklikethis:
pythonC:jarsSetClassPath.py%1%2%3%4%5%6%7%8%9
Ifyou'rerunningCygwin,youcanmakeashellfiletodothesamething:
pythonC:/jars/SetClassPath.py$1$2$3$4$5$6$7$8$9

ThisprogramrequiresPythonWin,whichyoucanfindat:
http://starship.python.net/crew/mhammond/win32/
"""
from _winreg import *
import os,glob,sys
import win32gui,win32con # FromPythonWin
path = r ' SYSTEMCurrentControlSetControlSessionManagerEnvironment '

def getClassPath():
try :
reg = ConnectRegistry(None,HKEY_LOCAL_MACHINE)
key = OpenKey(reg,path,0,KEY_ALL_ACCESS)
i = 0
while True:
try :
name,value,valueType = EnumValue(key,i)
if name == ' CLASSPATH ' :
return value
i += 1
except EnvironmentError:
return ""
finally :
CloseKey(key)
CloseKey(reg)

def setClassPath(newPath):
try :
reg = ConnectRegistry(None,HKEY_LOCAL_MACHINE)
key = OpenKey(reg,path,0,KEY_ALL_ACCESS)
SetValueEx(key, ' CLASSPATH ' ,0,REG_SZ,newPath)
win32gui.SendMessage(win32con.HWND_BROADCAST,win32con.WM_SETTINGCHANGE,0, ' Environment ' )
finally :
CloseKey(key)
CloseKey(reg)

if __name__ == ' __main__ ' :
# setpreventsduplicates,'ifos.path.exists(p)'prunesnonexistentpaths:
pathparts = set([p for p in getClassPath().split(os.pathsep) if os.path.exists(p)])
pathparts.add( " . " )
pathparts.add( " .. " )
if len(sys.argv) > 1 :
for arg in sys.argv[ 1 :]:
if not arg.endswith( " .jar " ):
print " Argumentsmustbejarfilenames:problemwith[ " + arg + " ] "
sys.exit( 1 )
if not os.path.exists(arg):
print arg, " doesnotexistinthisdirectory "
sys.exit( 1 )
pathparts.add(os.path.abspath(arg))
else :
jars = glob.glob( " *.jar " )
if jars:
for jar in jars:
pathparts.add(os.path.abspath(jar))
else :
pathparts.add(os.getcwd())
result = list(pathparts)
result.sort()
newClasspath = os.pathsep.join(result) + os.pathsep
setClassPath(newClasspath)
print getClassPath()