ONE SNIPPET PRO - PYTHON

One Snippet Pro is an initiative to learn and practice the programming in one snippet , We start learning a language or a technology using a simple hello world and we lean forward step by step to become a pro , But in this demo i am going to code it in to one snippet and cover as much as concepts possible. We have a lot of programming language and technologies in this series of "One Snippet Pro", The Post will have only two sections Simple introduction of the technology and One Snippet.

I am a big fan of game of thrones so most of the identifies , loops , destroying objects as a part of few snippets will have the logic play which you can relate to  Game of thrones.

You can email me at redhatvicky@gmail.com or twitter me at @rvigneshwaran88 for any queries ,suggestions and feedback. Would be very happy to take it.

Python :

Python is a general-purpose interpreted, interactive, object-oriented, and high-level programming language. It was created by Guido van Rossum during 1985- 1990. Like Perl, Python source code is also available under the GNU General Public License (GPL).

I have commit the same code in git , click here to get the git code

import time; #required inorder to use time module import calendar; #required inorder to use calender module

import math as mathInstance #user can import and rename and use the object

import os as osInstance #required inorder to use os module

import shutil as fileUtils #required in order to use high level file operations

import re as regexInstance #required in order to use regular expression

#Prints the content  (If you are running versions below 3)

#print "Hello, Python!"

#Prints the content (If you are running new version of Python)

print ("Hello World")

#Single and Multiline Commnets (All characters after the # and up to the end of the physical line is considered to be commented)

#print("Single line Comment")

#print("Multi Line Comment")

# ways of initializing the variables (5 Standard datatypes : Numbers,String,List,Tuple,Dictionary)

serialName = "Game of Thrones" #string data type

currentSeason = 7 #integer data type

averageDeathPerSeason = 177.57 #flating point datatype

gameOfThrones = aSongOfIceAndFire = createdBy = "George R. R. Martin" #multiLineAssignmnet

serialName,currentSeason,averageDeathPerSeason = " Game of Thrones ",7,177.57

# ways of concatinating and printing variables

print("Serial Name :: ",serialName," Current Season : ",currentSeason," Average Death Per Season : ",averageDeathPerSeason)

print(gameOfThrones,aSongOfIceAndFire)

# datatypes : Four types in the category numbers (int,long,float,complex)

# When user has multiline statements line continuation character (\) will solve the issue

total = "Game of Thrones " + \

"used seven writers " + \

"in six seasons"

print(total)

# datatypes : String

houseStark = 'EddardNedStark' #create String with single quote

houseStark = "EddardNedStark" #create String with double quote

#When we have multiple lines this triple quote is useful, we dont need a line contination character

houseStark = """EddardNedStark"""  #create String with triple quote

houseStark = '''EddardNedStark'''  #create String with triple quote

# Python allows negative indexing for its sequences,The index of -1 refers to the last item, -2 to the second last item and so on

print(houseStark)          # Prints full string

print(houseStark[0])      # Prints first character of the string

print(houseStark[-1])      # Prints last character of the string

print(houseStark[2:5])     # Prints characters starting from 3rd to 5th

print(houseStark[5:-2])   # Prints characters starting from 6th to 2nd last character

print(houseStark[2:])      # Prints string starting from 3rd character

print(houseStark * 2)     # Prints string two times

print(houseStark + "FROM WINTERFELL") # Prints concatenated string

print(houseStark * 2.5) #throws error "TypeError: string indices must be integers"

print(houseStark[125]) #throws error "IndexError: string index out of range"

print("Ned" in houseStark) #returns true if the string contains "Ned"

print("Ned" not in houseStark) #returns false as the string contains "Ned"

#Strings are immutable in python.

#houseStark[5] = 'a' #throws error "TypeError: 'str' object does not support item assignment"

#del my_string[1] #throws error "TypeError: 'str' object doesn't support item deletion"

#common python String methods

seasonOneEpisodeTwo = "the Kingsroad"

print(seasonOneEpisodeTwo.lower()) #Converts all uppercase letters in string to lowercase.

print(seasonOneEpisodeTwo.upper()) #Converts lowercase letters in string to uppercase.

print(seasonOneEpisodeTwo.split()) #Splits string according to delimiter str (space if not provided)

print("You#Win#or#You#Die".split("#")) #Splits string according to delimiter str (space if not provided)

print(" ".join(seasonOneEpisodeTwo)) #Merges (concatenates) the string representations of elements.

print(seasonOneEpisodeTwo.find('Kings')) #Determine if str occurs in string

print(seasonOneEpisodeTwo.capitalize()) #Capitalizes first letter of string

print(seasonOneEpisodeTwo.count("a")) #Counts how many times str occurs in string

print(seasonOneEpisodeTwo.endswith("road")) #Determines if string or a substring of string ends with suffix

print(seasonOneEpisodeTwo.isalnum()) #Returns true if string has at least 1 character and all characters are alphanumeric and false otherwise.

print(seasonOneEpisodeTwo.isalpha()) #Returns true if string has at least 1 character and all characters are alphabetic and false otherwise.

print(seasonOneEpisodeTwo.isdigit()) #Returns true if string contains only digits and false otherwise.

print(seasonOneEpisodeTwo.islower()) #Returns true if string has at least 1 cased character and all cased characters are in lowercase and false otherwise.

print(seasonOneEpisodeTwo.isnumeric()) #Returns true if a unicode string contains only numeric characters and false otherwise.

print(seasonOneEpisodeTwo.isspace()) #Returns true if string contains only whitespace characters and false otherwise.

print(seasonOneEpisodeTwo.istitle()) #Returns true if string is properly "titlecased" and false otherwise.

print(len(seasonOneEpisodeTwo)) #Returns the length of the string

print(max(seasonOneEpisodeTwo)) #Returns the max alphabetical character from the string seasonOneEpisodeTwo.

print(min(seasonOneEpisodeTwo)) #RReturns the min alphabetical character from the string seasonOneEpisodeTwo.

print(seasonOneEpisodeTwo.isdecimal()) #Returns true if a unicode string contains only decimal characters and false otherwise.

#pythonLists : similar to arrays but lists can hold items of hetrogeneous data type

listInstanceFirst = ["David Benioff & D. B. Weiss","Tim Van Patten"]

listInstanceSecond = ["Brian Kirk","Daniel Minahan","Alan Taylor"]

listConsolidated = listInstanceFirst + listInstanceSecond

nestedListInstance = ["Fire and Blood", ["Robb", "the king", "Jaime","captured by the Starks"], [10],'T'] #create a nested list

print(listInstanceFirst) #prints the whole list

print(listInstanceFirst[0]) #prints first element in the list

print(listInstanceFirst[-1]) #prints the last element in the list

print(listConsolidated[2:5])

print(listConsolidated[1:]) #prints from the elements starting from 2nd position

print(listConsolidated[:-5]) #prints from negining to the fourth

print(listConsolidated[:]) #prints element from beginning to the end

#add of delete any elements from the list

seasonOneEpisodesList = ["The Kingsroad","The Wolf and the Lion","A Golden Crown","You Win or You Die","The Pointy End",

"Baelor","Fire and Blood"]

seasonOneEpisodesList[0] = "Winter Is Coming" #insert in the respective index of the list

print(seasonOneEpisodesList)

seasonOneEpisodesList[1:4] = ["Lord Snow","Cripples, Bastards, and Broken Things"] #insert multiple items in position of the list

print(seasonOneEpisodesList)

seasonOneEpisodesList.append("The Kingsroad")

print(seasonOneEpisodesList)

seasonOneEpisodesList.append(["The Wolf and the Lion","A Golden Crown","You Win or You Die"])

print(seasonOneEpisodesList)

del seasonOneEpisodesList[0:2] # delete mltiple items in the list

print(seasonOneEpisodesList)

#More functions to manage a list

newListInstance = ['R','o','b','e','r','t','B','a','r','a','t','h','e','o','n']

newListInstance.remove('o') #removes the respective element from the list

print(newListInstance.pop(1)) #pops out respective element in the lisst

print(newListInstance.pop()) #pops out last element from the list

newListInstance.clear() # removes all the element from the list

print(newListInstance)

appendNewListInstance = ['H','a','m','m','e','r']

newListInstance.append(appendNewListInstance) # Add all elements of a list to the another list

print(newListInstance)

newListInstance.insert(4,appendNewListInstance) #Insert an item at the defined index

print(newListInstance)

print(appendNewListInstance.index('H')) #Returns the index of the first matched item

appendNewListInstance.sort()  #Sort items in a list in ascending order

print(appendNewListInstance)

appendNewListInstance.sort(reverse=True) #sort in descending order

print(appendNewListInstance)

newListInstance.reverse() #Reverse the order of items in the list

print(newListInstance)

print(newListInstance.copy()) #Returns a shallow copy of the list

#data type : Python Tuples : similar to the list but enclosed within parentheses.

# Tuple are immutable, iterating through tuple is faster than with list , write protected,

# Tuples that contain immutable elements can be used as key for a dictionary

tupleInstance = ()

tupleInstance = ("Catelyn Stark", "Sansa Stark", "Arya Stark","Robb Stark","Bran Stark")

tupleInstance = (22, "Jaime Lannister", 45)

tupleInstance = ("Viserys Targaryen", [82, 14, 63], (134, 221, 312))

tupleInstance = 3, 4.6, "Tyrion Lannister"

a, b, c = tupleInstance

print(a)

print(b)

print(c)

#creating tuple with one elements has a problem

tupleInstance = ("Cersei Lannister")

print(type(tupleInstance)) # this will result in the data type string <class 'str'>

tupleInstance = ("Daenerys Targaryen",)

print(type(tupleInstance)) # this will result in the data type tuple <class 'tuple'>

tupleInstance = "Jon Snow",

print(type(tupleInstance)) #this will result in the data type tuple <class 'tuple'>

# We can manage tuble as we manage the list

#additionals methods in a tuple

print(any(tupleInstance)) #Return True if any element of the tuple is true. If the tuple is empty, return False.

print(all(tupleInstance)) #Return True if all elements of the tuple are true (or if the tuple is empty).

print(len(tupleInstance)) #Return the length (the number of items) in the tuple.

print(max((82, 14, 63))) #Return the largest item in the tuple.

print(min((82, 14, 63))) #Return the smallest item in the tuple

print(sorted(tupleInstance)) #Take elements in the tuple and return a new sorted list (does not sort the tuple itself).

print(sum((82, 14, 63))) #             Retrun the sum of all elements in the tuple.

#Convert an iterable (list, string, set, dictionary) to a tuple.

print(tuple("Daenerys Targaryen"));

print(tuple(["Catelyn Stark", "Sansa Stark", "Arya Stark","Robb Stark","Bran Stark"]));

# data type : Dictionary : hash table type.

dictionaryInstance = {}

dictionaryInstance = {1: 'Winter Is Coming',2:'The Kingsroad',3:'Lord Snow'}

dictionaryInstance = {1: 'Winter Is Coming','WinterIsComing':["White Walkers","Eddard Ned Stark","Jon Arryn"

"King Robert Baratheon"]}

print(dictionaryInstance.get('WinterIsComing')) #using get to access elements

print(dictionaryInstance['WinterIsComing']) # directing acces using the key in dictionary

#create dictionary using the dict command

dictionaryInstance = dict({6:'A Golden Crown', 7:'You Win or You Die',8:'The Pointy End',9:'Baelor',10:'Fire and Blood'})

print(dictionaryInstance.get(7))

dictionaryInstance = dict([(4,'Cripples, Bastards, and Broken Things'), (5,'The Wolf and the Lion')])

print(dictionaryInstance[5])

# To print keys and values of the dictionary

print(dictionaryInstance.keys())   # Prints all the keys of the disctionary

print(dictionaryInstance.values()) # Prints all the values of the disctionary

#Arthimatic operators  a**b (exponential (power)) a//b (Floor Division)

a,b = 10,20

print(" a+b :",(a+b)," a–b :",(a-b)," a*b :",(a* b)," b/a :",(b / a)," b%a :",(b % a)," a**b :",(a**b)," a//b : ",a//b)

#Comparison Operators

print(" a == b :",(a == b)," a > b :",(a > b)," a < b :",(a < b)," a >= b :",(a >= b)," a <= b :",(a <= b))

#Bitwise Operators

print(" a & b :",(a & b)," a | b :",(a | b)," a ^ b :",(a ^ b)," ~a :",(~a)," a << 2 :",(a << 2)," a >> 2 :",(a >> 2))

#Membership Operators

listInstanceMem = [21,45,67,78,54,32]

print (75 in listInstanceMem) #Evaluates to true if it finds a variable in the specified sequence and false otherwise.

print (71 not in listInstanceMem) #Evaluates to true if it does not find a variable in the specified sequence and false otherwise.

#Identity Operators

print (a is b) #Evaluates to true if the variables on either side of the operator point to the same object and false otherwise.

print (a is not b) #Evaluates to false if the variables on either side of the operator point to the same object and true otherwise.

# Flow Control : if and else

# if Clause

king = "Robert Baratheon"

if king.endswith("Baratheon"):

print("Yes,He is a baratheon")

print("This is a common block which is printed always")

#if else and elif

if king.endswith("Targaryen"):

print("Yes,He is a Targaryen")

elif king.endswith("Stark"):

print("Yes,He is a stark")

elif king.endswith("Baratheon"):

print("Yes,He is a baratheon")

else:

print("random people in got")

#Flow Control : for loop

stark = ["Catelyn Stark", "Sansa Stark", "Arya Stark","Robb Stark","Bran Stark"]

for indv in stark:

print("Pointer is at :: ",indv)

print(range(10)) # generates sequence of numbers using range function

print(list(range(10))) # sets the range of numbers from 0 to 9 in a List and prints it

print(list(range(1,10))) # sets the range of numbers from index 1 to 9 in a List and prints it

print(list(range(2, 20, 3))) #firstParamter(2)=start,secondParamter(20)=stop,thirdParameter(3)=step

#using ranges to determine the length

for indv in  range(len(stark)):

print("Pointer is at :: ",indv," value is : ",stark[indv])

#use for with else : "Else is executed when there is no break in the for loop"

for indv in range(len(stark)):

print("killing :: ",stark[indv])

else:

print("No starks left to kill !!! Red Wedding " )

# Flow control : While Loop

# While with optional else (The else part is executed if the condition in the while loop evaluates to False)

totalNumber,sumOfItems,index = 10,0,1

while index <= totalNumber:

sumOfItems = sumOfItems + index

index = index+1

else:

print("Conditional false else")

print("The sumOfItems is", sumOfItems)

#Time functions

timeInstance = time.localtime(time.time())

print("Local current time :", timeInstance)

#Formattng Time according to the user requirement

timeInstance = time.asctime(time.localtime(time.time()) )

print("Local current time :", timeInstance)

#To Display calender of the respective month

calenderInstance = calendar.month(2017, 2)

print(calenderInstance)

# Function is a group of related statements that perform a specific task

# Function creation (def is a keyword) def functionname(parameter1,parameter2):

def greet(name):

"""This content is a docstring,generally docstrings are

enclosed within triple quoteswhich can extend

up to multiple lines , this is strored in __doc__

attribute"""

print("Good morning ",name)

greet("Samwell Tarly")

# docstring attribute with method call

print(greet.__doc__)

# if we dont provide arguement to the method it results in TypeError, but we can provide default arguements

def greet(name, msg = "Good morning !!! "):

print(msg + name)

greet("Samwell Tarly ","Good Noon !!! ")

greet("Samwell Tarly ")

#anonymous function : function without a name (represented using a keyword called lambda)

# will use the same function greet as the anonymous function

sendGreetings = lambda name : print ("Good Morning !!! ",name)

sendGreetings("Samwell Tarly ")

# Usage of map and Filter with anonymous functions

listRangeInstance = list(range(10))

filteredListinstance = list(filter(lambda x: (x%2 == 0),listRangeInstance))

mapListinstance = list(map(lambda x: x^2,listRangeInstance))

print("Map Applied Value ::",mapListinstance,"Filter Applied Value : ",filteredListinstance)

# Usage of variable arguements in a function

def sumOfItems(operation="add",*objectList):

sum = 0

for index in objectList :

sum = sum + index

print("The Sum of all elements in the list is :: ",sum)

#ret accessed globally from that function.

print(globals())

#If locals() is called from within a function, it will return all the names that can be accessed locally from that function.

print(locals())

sumOfItems("add",10,20,30) # this will yield the sum as 60

sumOfItems("add",10,20,30,40) #this will yield the sum as 100

#Mathematical Functions

print(mathInstance.pi) #mathematical Constant

print(mathInstance.factorial(22)) # factorial of a number

print(mathInstance.sqrt(225)) #factorial of a number

print(mathInstance.isnan(22)) #check whether its a number or not

print(mathInstance.exp(2)) #exponent function

print(mathInstance.e) #mathematical Constant

#The dir() built-in function returns a sorted list of strings containing the names defined by a module.

print(dir(calendar))

#Basic File Operations and exceptions

try:

fileInstance = open("test.txt",encoding = 'utf-8')

#Read the file line by line

for lineReader in fileInstance :

print(lineReader, end = '')

#method reads a file till the newline, including the newline character.

print(fileInstance.readlines())

finally:

fileInstance.close()

#Alternative way to open a file using "with" keyword,We don't need to explicitly call the close() method.

with open("pythonTags.txt",encoding = 'utf-8') as fileInstance:

print(fileInstance.read()) #Read the contends in the file

print(fileInstance.read(4)) #Read the first 4 data

print(fileInstance.tell()) #Get the current file position

print(fileInstance.seek(0)) #Bring the cursor to the zeroth position

print(fileInstance.name) #get the fileName from the file instance

print(fileInstance.closed) # to Know whethre the file is closed or not

print(fileInstance.mode) # to Know the opening mode of the file

#Directory Operations

print(osInstance.getcwd()) # get the current working directory

print(osInstance.getcwdb()) # get the current working directory as byte object

#osInstance.chdir("C:\\")

#print(osInstance.getcwd()) #printing after changing the directory

print(osInstance.listdir()) # to list all the directoris and files

#osInstance.mkdir('test') #make a new directory

#osInstance.rename('test','modfied') rename a directory

#osInstance.remove('test.txt') #to remove a file

#osInstance.rmdir('modfied') #to remove a directory

#fileUtils.rmtree('test') #Delete an entire directory tree;

class Playaround:

"""This is a docString for class, we can access using

__doc__ attribute"""

def __init__(self,firstNum=10,secondNum=10):

self.a = firstNum

self.b = secondNum

a,b = 20,30

def add(self):

print(a+b)

def greet(self):

print("Good Morning ,The Value of a is ",self.a,"The Value of b is ",self.b)

print("Playaround.a : ",Playaround.a,"Playaround.b : ",Playaround.b)

print("Playaround.add : ",Playaround.add) #call the method inside the class

print("Doc string of the class :: ",Playaround.__doc__) #display the doc string of the class

newObjectInstance = Playaround() # Object creation

print("The Value of a is ",newObjectInstance.a,"The Value of b is ",newObjectInstance.b)

print(newObjectInstance.add) #<bound method Playaround.add of <__main__.Playaround object at 0x004EA430>>

newObjectInstance.add() # method call from the object

newObjectInstance.greet() # method call from the object

#One More class Sample

class Targaryen:

count = 0

def __init__(self,name):

self.name = name

Targaryen.count += 1

def displayTargaryanCount(self):

print("The Count of the Targaryen is :: ",Targaryen.count)

def displayTargaryan(self):

print("The Targaryen is called :: ",self.name," Targaryen")

#Creating Objects

duncanInstance = Targaryen("Duncan")

rhaellaInstance = Targaryen("Rhaella")

aegonInstance = Targaryen("Aegon")

viserysInstance = Targaryen("Viserys")

#access using the object created

rhaegarInstance = Targaryen("Rhaegar")

rhaegarInstance.displayTargaryan()

# Manipulating attributes of an object

daenerysInstance = Targaryen("Daenerys")

print(hasattr(daenerysInstance, 'name')) # Returns true if 'name' attribute exists

print(getattr(daenerysInstance, 'name')) # Returns value of 'name' attribute

setattr(daenerysInstance, 'name', "Khaleesi") # Set attribute 'name' at Khaleesi

daenerysInstance.displayTargaryan()

#delattr(daenerysInstance, 'name') # Delete attribute 'age'

# Accessing the Glaobal varibale in the class

print("The Count of the Targaryen is ",Targaryen.count)

# More build in Attributes of the class

print("Targaryen.__doc__:", Targaryen.__doc__) #to get the class documentation

print("Targaryen.__name__:", Targaryen.__name__)  # to retrive the classname

print("Targaryen.__module__:", Targaryen.__module__) #to get the module name in which the class is defined

print("Targaryen.__dict__:", Targaryen.__dict__) #Dictionary containing the class's namespace.

#Inheritance #Stark Here is a Parent Class and Westeros is a Child Class

class Stark:

def __init__(self,firstName,secondName):

self.firstName = firstName

self.secondName = secondName

def displayFullName(self):

return self.firstName + " " +  self.secondName

class Westeros(Stark):

def __init__(self,firstName,secondName,placeName):

Stark.__init__(self,firstName,secondName) #refer the parent class init

self.placeName = placeName

def getDetails(self):

return "He is named :: ",self.displayFullName," from ",self.placeName

starkInstance = Stark("Ned","Stark")

print(starkInstance.displayFullName())

westerosInstance = Westeros("Catelyn","Stark","The Winterfell")

print(westerosInstance.getDetails())

#Regular Expression

inputLine = """Winterfell is the name given to the ancestral castle of House Stark.

It is built over a natural hot spring and the scalding water runs through the castle walls, warming halls and rooms."""

print(regexInstance.findall(r'is', inputLine)) # Find all instance of the word

matchInstance = regexInstance.search(r'is', inputLine) #Match the content any where

print(matchInstance.group(0))

#The match object can tell us the start and end indexes also here below is the sample

print(matchInstance.start())

print(matchInstance.end())

# parse by groups

westerosInformation = 'Essos, Climate: Mediterranean climate'

matchInstance = regexInstance.search(r'(\w+), (\w+): (\S+)', westerosInformation)

print("matchInstance.group(1) :: ",matchInstance.group(1))

print("matchInstance.group(2) :: ",matchInstance.group(2))

print("matchInstance.group(3) :: ",matchInstance.group(3))

# we can use find all with this snippet

print(regexInstance.findall(r'(\w+), (\w+): (\S+)', westerosInformation))

# we can set a name to that group and access by the name

matchInstance = regexInstance.search(r'(?P<placeInWesteros>\w+), (?P<type>\w+): (?P<info>\S+)', westerosInformation)

print("matchInstance.group(1) :: ",matchInstance.group("placeInWesteros"))

print("matchInstance.group(2) :: ",matchInstance.group("type"))

print("matchInstance.group(3) :: ",matchInstance.group("info"))

# Iterators two methods __iter__() and __next__()

westerosList = ["The North ","Winterfell","The Iron Islands","The Riverlands","The Stormlands"]

iteratorInstance = iter(westerosList)

while True:

try:

pointer = next(iteratorInstance)

print(pointer)

except StopIteration:

break

EXECUTING PYTHON SNIPPET FROM JAVA 

When i was researching on ways to call or execute python snippet in java landed up in three ways one is conventional way of doing it using old run time classes to call it , The next one is using Process builder classes to call it and the last one is using the Jython (serves as a python interpreter) which is written in java. 

In this current post i will be posting few snippets how to do it through process builder classes.

When the python program does not have any command line arguments

Code Snippet: 

package com.connectors.python;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

public class TestRuntimeConnector {

      

  public static void getOutputAsString(Process processInstance){

         String stringInstance = null;

         try {

         BufferedReader stdInput = new BufferedReader(new InputStreamReader

                       (processInstance.getInputStream()));

      BufferedReader stdError = new BufferedReader(new InputStreamReader

                (processInstance.getErrorStream()));

      while ((stringInstance = stdInput.readLine()) != null) {

        System.out.println(stringInstance);

      }

      System.out.println("Here is the standard error of the command (if any):\n");

      while ((stringInstance = stdError.readLine()) != null) {

        System.out.println(stringInstance);

      }

      System.exit(0);

    }catch (IOException e) {

      System.out.println("exception happened - here's what I know: ");

      e.printStackTrace();

      System.exit(-1);

    }

  }

  public static void main(String args[]) {

    try {

     long startTime = System.nanoTime();

     Process processInstance = Runtime.getRuntime().exec

                (new String[]{"python","sample.py"});

     long endTime = System.nanoTime();

     long duration = (endTime - startTime)/1000000;

     System.out.println("The Time taken to execute the method is "+duration+"milli seconds");

        getOutputAsString(processInstance);

       } catch (IOException exception) {

         exception.printStackTrace();

       }

  }

}

When the python program has command line arguments and you need to pass the command line arguments in method mentioned in the below snippet.

Process randomNumberInstance = Runtime.getRuntime().exec

     (new String[]{"python","randomNumber.py","10"});

Moreover if you need to pass multiple arguments, pass one by one separate it by comma.

Get the file Name from the Path using java.nio.file.Paths API

Code Snippet : 

import java.nio.file.Path;

import java.nio.file.Paths;

public class GetFileName {

       public static void main(String[] args) {

              String filePath = "MESSAGE_PATH";

              Path p = Paths.get(filePath);

              String fileName = p.getFileName().toString();

              int index = fileName.indexOf(".");

              String mainChapterNumber = fileName.substring(0,index);

              System.out.println(mainChapterNumber);

       }

}

Retrieve all Dependencies from the pom.xml

Code Snippet : 

package com.bnp.pomparser;

import java.io.FileReader;

import java.io.IOException;

import java.io.Reader;

import java.util.List;

import org.apache.maven.model.Dependency;

import org.apache.maven.model.Model;

import org.apache.maven.model.io.xpp3.MavenXpp3Reader;

import org.codehaus.plexus.util.xml.pull.XmlPullParserException;

public class ParseMe {

       public static void main(String[] args) throws IOException, XmlPullParserException {

         Reader reader = new FileReader("POM_XML_PATH");

         try {

           MavenXpp3Reader xpp3Reader = new MavenXpp3Reader();

           Model model = xpp3Reader.read(reader);

           List<Dependency> dependencyList = model.getDependencies();

           for(Dependency dependency : dependencyList){

             System.out.println("Group Id :: "+dependency.getGroupId());

             System.out.println("Artifact Id :: "+dependency.getArtifactId());

             System.out.println("Version Id :: "+dependency.getVersion());

           }

         } finally {

           reader.close();

         }

       }

}