Java vs. Python: Which Is the Best Programming Language for You?

Java and Python are both excellent choices for a beginning programmer. You really can’t go wrong by choosing either one. Here are some things these languages have in common.

• Both are popular and in high demand.
• Both are open source and don’t require a paid license to use for developers.  In the case of Java, if you use the official Oracle Java version, there may be a fee for commercial use payable by your customer/employer when deploying your Java application.  However, there are free runtime versions available from multiple vendors as well. 
• You can get started coding in either language today as long as you have an internet connection to download the installation files and a computer that runs Windows, OS X, or Linux.

The two languages do have their differences, and developers sometimes prefer one or the other for various reasons. Below is a discussion of those reasons, with hopefully enough information to help you decide which language is the one for you.

Learning curve and readability

This factor matters to a lot of developers when they are beginning. How easy is the programming language to read and learn? And the answer is: It depends.

Java

The learning curve for anything depends on what you already know, how interested you are in learning the topic, and the learning environment. For example, if you have already done some type of coding or scripting, even if it is pasting some JavaScript into a web page, you may be familiar with the code structure you will run into with a language like Java. Here is an example of Java code:

public class AddTwoIntegers {
public static void main(String[] args) {
int first = 10;
int second = 20;
System.out.println("Enter two numbers: " + first + " " + second);
int sum = first + second;
System.out.println("The sum is: " + sum);
}
}

Java also supports multiple programming paradigms, including object-oriented programming and functional programming.

Writing code in Java is heavily tied to using classes and then using those classes to create objects.  Although possible, it’s not a language that you would generally use for a simple one-off script. 

Python

If you are a beginner and find the code above hard to read, then Python may be a good choice. Readability is only one of this language’s claims to fame. Here is an example of Python code:

# This program adds two numbers
num1 = 10
num2 = 10
# Add two numbers
sum = num1 + num2
# Display the sum
print('The sum of {0} and {1} is {2}'.format(num1, num2, sum))

If you never programmed before, Python code is usually easier to read. You can also use simpler code structures to get the result you want. For this reason, it is a very popular language for writing quick scripts. It is also used widely in the scientific community, where the programming language is just considered another tool to use, not a career choice.

Python is also a multiparadigm language. It supports object-oriented programming, functional programming, and procedural programming, and you can use all of these paradigms in the same application. This means you can customize parts of your application to their functionality instead of relying on just one programming paradigm.

Syntax

We touched on syntax in the last section. Now we are going to look at it in depth. There are quite a few differences in syntax between the two languages, and these differences are a big reason developers choose one language or the other.

Java

Here is another sample of Java code:

public class Fruit {
String name;
String color;

public Fruit(String name, String color) {
this.color = color;
this.name = name;
}

public void myname() {
System.out.println("Hello I'm a :" +name);
}

public void mycolor() {
System.out.println("Hello my color is:" + color);
}
}

Fruit fruit = new Fruit("Apple", "red");
fruit.myname(); // prints: Hello I'm an Apple
fruit.mycolor(); // prints: Hello my color is red

Here is what you should know about the code above:

• Curly braces define the blocks of code. The Fruit class above and its methods are surrounded by {}. Curly braces also define loops in Java code.
• Each statement must end in a semicolon.
• Each time you create a new variable, it must have a type. When we instantiate the fruit object, we have to declare it as a Fruit type.
• Whitespace does not matter with Java. The Java code above is formatted nicely, but it would also run if everything were on one line as long as the code follows other syntax rules.
• You will also notice how verbose the code is. You will usually end up typing more writing Java code than you would with Python code.

This is a similar syntax that you will run into with other programming languages, including:

• C++
• JavaScript
• Objective C
• C#

The syntax might be complicated, but what you learn from Java will give you a head start learning these other popular languages.

Python

Here is a sample of Python code that does the same as the Java code above:

class Fruit:

def_init_(self, name, color):
self.name = name
self.color = color

def myname(self):
print("Hello I'm a "+ self.name)

def mycolor(self):
print("Hello my color is " + self.color)

fruit = Fruit("Apple", "red")
fruit.myname() # prints: Hello I'm a Apple
fruit.mycolor() # prints: Hello my color is red

Here’s what you should notice about the Python code above:

• Line breaks define blocks of code in Python. Everywhere there is a set of brackets in the Java code, there is an indentation in the Python code. This means hitting tab or space (or multiple spaces) to start a new line of code; there are no extra symbols. The indentions have to be consistent. If you use two spaces in your first indention, you must continue to use two spaces throughout the code file, or it will throw an error.
• There is no need for semicolons. But Python does use a colon to start classes, methods, and loops. You see that in the Fruit class above and its methods.
• We can create a fruit object without using new or assigning it the type of Fruit.
• Whitespace is important to Python. Developers use it to define blocks of code, so the lines in the code above could not run on one line.
• The Python Fruit class is more compact than the equivalent Java Fruit class.

The syntax of Python is fairly unique to programming languages. There are a few languages that come close to its syntax — like CoffeeScript, which compiles to JavaScript — but not many. Still, many developers find the Python syntax easier to manage, especially when they are beginning.

Types

Another difference is in the way both languages handle types. In short, Java is statically typed, while Python is dynamically typed.

Java

In Java, when you create an object, you always need to specify its type. For example, let’s say we want to create an integer and a String type. You must explicitly specify the type for each one:

int var1 = 10
String var2 = "Hello World";

Once variables in Java initialize, we cannot assign any other value that doesn’t match their original type. Going off the example above, var1, an integer, can never be assigned a String like “Hello World.” This might seem restrictive on some levels, but your code will naturally be less prone to errors, as the restriction will catch any typos or mistakes while the code is compiling.

Python

Variables in Python are strongly but dynamically typed, meaning any variable can take on any type — it doesn’t matter. For example:

x = 10 + 12
x = "Hello World"

The above statements are totally legal in Python. The reason for this is Python’s interpreter, which reads and handles variables as they come. Because Python interprets your code, it doesn’t have the typing checks that Java would have. This lack of restriction can be pretty convenient, but accidentally using variables as the wrong type can also cause a lot of issues while your program is running, so it’s a trade-off.

Building and running

A big difference between Java and Python is how both languages are built and run.

Java

Once your code is ready in Java, you need to compile it into Java Bytecode in order to be able to execute the code.

The build output (or the artifact) of your code comes in the form of .class files.

In order to execute a .class file, you need a Java RunTime Environment (JRE) installed on that computer.  A .class file can execute on any platform that has a version of the JRE, and almost all modern operating systems have a version available.

You can also build your project as a .jar file that conveniently packages up your .class files and there are commercial products that make it possible to package the code into an executable format.

As mentioned, a .java file won’t do you much good because they need to compile it first into a .class file.  In order to do this, you need to have the Java Development Kit (JDK) installed which includes the Java compiler.

So in a nutshell, Java code needs to be compiled into Java Bytecode in the form of a .class file to then execute under the JRE.

There are a lot of steps to set up your program.

Python

Python, on the other hand, is a scripting language. When you code a .py file, you don’t need to compile the code before running it. For Python, and other scripting languages as well, you need an interpreter to run your code. You can download Python’s interpreter from its official website.

When you launch the Python interpreter, it will display a prompt where you can input lines of Python code and present results for each line. While you can compile Python into .pyc files, which allows the interpreter to run your program more efficiently, you aren’t required to in order to build your project. Once you code something in Python, you just need to run the interpreter with your .py file, and that’s it!

Both languages are cross-platform, so you can run them on Windows, OS X, Linux, and other platforms.

Performance

Programmers consider interpreted languages to be slow. Since Python is interpreted and Java is compiled, Python is slower than Java —  but sometimes it does not matter as much as you think.

If the requirements for your application are to squeeze every bit of performance out of a machine, then you should choose Java. But most of the time, you do not need this type of performance. And often, the difference in performance between Java and Python for a particular use case won’t be in magnitudes, it will only be in percentages.

In addition, modern, fast computers execute Java and Python code quickly and help to reduce the requirement to pick a language purely for performance reasons.

It depends on what you need to do and the environment you are working in. The libraries and the coding style you use also matter a lot. Python offers multiple coding styles, and the one you choose will affect the performance of your application. The version of Python you use also matters. Python 3.x will generally run faster than Python 2.x.

It’s highly recommended to use Python 3.x because as of January 2020, Python 2.x has no official support.

Performance can be a hard metric to measure. It depends on the environment, libraries, and versions of the language you are using and the hardware the code is executing on.

If performance is the top requirement of your project, then Java is probably the language you want, but if it doesn’t matter that much, you can still write Python code that performs well.

Community and popularity

When you are a beginner, learning a popular language means that you will be able to find plenty of tutorials and articles on the language. When you are building a full-scale application, a popular language will have plenty of third-party libraries that you can add to your project to make development quicker and more bug-free.

Is Python or Java more popular? It is hard to tell. The contest between these two languages and JavaScript for the top 3 slots in popular programming languages has been going on for years, and the trend seems to be continuing.

If you are interested in learning Java, you can find a Java User Group (JUG) in most areas of the world. There is probably one in your city. You can find more information about those groups at the Java Community Process Program site. There are also high-profile Java conferences to attend, like JavaOne.

If you are leaning toward Python, there are just as many groups out there that can help you find your way. There are over 1,637 Python user groups in 191 cities and 37 countries with over 860,000 members. Python also has popular conferences like PyCon where Python developers from around the world meet up.

As far as community and popularity go, Java and Python are pretty equal.

Use cases

While both Python and Java have been used to create the same type of software and can be interchangeable in a few projects, there are applications where one language is more preferable. Here are some places where both languages are frequently used:

• Web applications
• Game development

Now let’s look at where each of these languages shine.

Java

You may have heard the phrase: Java is everywhere. The Java Virtual Machine has been ported to not just operating systems, but mobile phones, smart TVs, and other devices. Its object-oriented paradigm is also suited to large-scale applications like those you will find in enterprise development. Here are some places you will find Java used:

• Android phone app development
• Desktop applications
• Enterprise software
• Embedded systems

Python

Python is popular among scientists and mathematicians, so while both languages are used for machine learning, you will find more libraries for processing data in Python. Here are some places you will find Python:

• Machine learning
• Scientific computing
• Data processing
• Scripting
• DevOps

Jobs and salaries

The use cases above will give you an idea of what kind of work you will do with either Python or Java. So you could end up working on different projects depending on your choice, but as far as salary goes, you can find a well-paying job writing either Python or Java code. Both languages are consistently in the top three popular programming languages, so it figures that the pay would be around the same. This is another category where other factors may matter more in your choice, like the type of projects you will be working on.

Conclusion

There are many things you need to consider when choosing a programming language. Here is a breakdown of what we just covered:

Comparison	Python	Java
Learning curve and readability	Easy	Not as easy
Syntax	Whitespace and indentions	Brackets and semicolons
Types	Dynamic	Static
Building and running	Executed by the Python Interpreter	Compiled, then run on the JVM
Performance	Slower than Java	Relatively fast
Community and popularity	Very popular	Very popular
Use cases	Android, enterprise development	Machine learning, data processing
Jobs and salaries	Well paying	Well paying

You can’t really go wrong with either choice. You will find many tutorials and much support, no matter which language you choose. If you are new to programming languages, then Python may be an excellent choice. Many beginning programmers say that the syntax is more like a regular language and is easier to understand. If you want to get into enterprise development, then you may want to take a look at Java. It all comes down to what you prefer. Try each language and form your own opinion. And it never hurts to learn both eventually.