Python vs Java comparison

1. Difference Between Python vs Java

The last session was on the pros and cons of Python. In this Python Vs Java Tutorial, we will study a basic difference between java and python. The comparison between Java and Python on the basis of syntax, simplicity, speed, interpreted, database accessibility etc.

So, let’s start Python Vs Java.

2. Hello World in Java and Python

To rigorously compare Python and java, we first compare the first program in any programming language- to print “Hello World”.

• java

• Python

Now, let’s try printing the same thing in Python.

As you can see, what we could do with 7 lines of code in Java, we can do with 1 line in Python.

Let’s further discuss parts of this program, and other things.

3. Python vs Java — Syntax

A striking characteristic of Python is simple python syntax. Let’s see the subtle differences.

a. Semicolon

Python statements do not need a semicolon to end, thanks to its syntax.

But it is possible to append it. However, if you miss a semicolon in Java, it throws an error.

Compilation error #stdin compilation error #stdout 0.09s 27828KB

Main.java:10: error: ‘;’ expected

1 error

b. Curly Braces and Indentation

In Java, you must define blocks using semicolons. Without that, your code won’t work. But Python has never seen a sight of curly braces. So, to define blocks, it mandates indentation. Some lazy programmers don’t go the extra mile to indent their code, but with Python, they have no other choice. This indentation also aids readability. But you must compliment the indentation with a colon ending the line before it.

Greater

This code would break if we added curly braces.

SyntaxError: expected an indented block

Now, let’s see if we can skip the curly braces and indentation in Java.

Success #stdin #stdout 0.09s 28020KB

Lesser
As you can see here, 2 isn’t less than 1, so the if statement’s body isn’t executed. Since we don’t have curly braces here, only the first print statement is considered to be its body. This is why here, only the second statement is executed; it isn’t in the if’s body.

c. Parentheses

Starting Python 3.x, a set of parentheses is a must only for the print statement. All other statements will run with or without it.

Hello

SyntaxError: Missing parentheses in call to ‘print’

This isn’t the same with Java, where you must use parentheses.

d. Comments

Comments are lines that are ignored by the interpreter. Java supports multiline comments, but Python does not. The following are comments in Java.

Now, let’s see what a comment looks like in Python.

Here, documentation comments can be used in the beginning of a function’s body to explain what

it does. These are declared using triple quotes (“””).

These were the Python vs Java Syntax comparison

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4. Python vs Java — Dynamically Typed

One of the major differences is that Python is dynamically-typed. This means that we don’t need to declare the type of the variable, it is assumed at run-time. This is called Duck Typing. If it looks like a duck, it must be a duck, mustn’t it?

You could reassign it to hold a string, and it wouldn’t bother.

In Java, however, you must declare the type of data, and you need to explicitly cast it to a different type when needed. A type like int can be casted into a float, though, because int has a shallower range.

Success #stdin #stdout 0.09s 27788KB

10.0

However then, at runtime, the Python interpreter must find out the types of variables used. Thus, it must work harder at runtime.

Java, as we see it, is statically-typed. Now if you declare an int an assign a string to it, it throws a type exception.

Compilation error #stdin compilation error #stdout 0.09s 27920KB

Main.java:12: error: incompatible types: String cannot be converted to int

1 error

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5. Python vs Java — Verbosity/ Simplicity

Attributed to its simple syntax, a Python program is typically 3–5 times shorter than its counterpart in Java. As we have seen earlier, to print “Hello World” to the screen, you need to write a lot of code in Java. We do the same thing in Python in just one statement. Hence, coding in Python raises programmers’ productivity because they need to write only so much code needed. It is concise.
To prove this, we’ll try to swap two variables, without using a third, in these two languages. Let’s begin with Java.

Success #stdin #stdout 0.1s 27660KB

20 10

Now, let’s do the same in Python.

(3, 2)

As you can see here, we only needed one statement for swapping variables a and b. The statement before it is for assigning their values, and the one after is for printing them out to verify that swapping has been performed. This is the main point in Python vs Java.
Winner– Python

6. Python vs Java — Speed

When it comes to speed, Java is the winner. Since Python is interpreted, we expect them to run slower than their counterparts in Java. They are also slower because the types are assumed at run time. This is extra work for the interpreter at runtime. The interpreter follows REPL (Read Evaluate Print Loop). Also, the IDLE has built-in syntax highlighting, and to get the previous and next commands, we press Alt+p and Alt+n respectively.

However, they also are quicker to develop, thanks to Python’s brevity. Therefore, in situations where speed is not an issue, you may go with Python, for the benefits it offers more than nullify its speed limitations. However, in projects where speed is the main component, you should go for Java. An example of such a project is where you may need to retrieve data from a database. So if you ask Python or Java as far as speed is concerned, Java wins.

Winner– Java

7. Python vs Java — Portability

Both Python and Java are highly portable languages. But due to the extreme popularity of Java, it wins this battle. The JVM (Java Virtual Machine) can be found almost everywhere. In the Python versus Java war of Portability, Java wins.

Winner– Java

8. Python vs Java — Database Access

Like we’ve always said, Python’s database access layers are weaker than Java’s JDBC (Java DataBase Connectivity). This is why it isn’t used in enterprises rarely use it in critical database applications.

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9. Python vs Java — Interpreted

With tools like IDLE, you can also interpret Python instead of compiling it. While this reduces the program length, and boosts productivity, it also results in slower overall execution.

10. Python vs Java — Easy to Use

Now because of its simplicity and shorter code, and because it is dynamically-typed, Python is easy to pick up. If you’re just stepping into the world of programming, beginning with Python is a good choice. Not only is it easy to code, it is also easy to understand. Readability is another advantage. However, this isn’t the same with Java. Because it is so verbose, it takes some time to really get used to it.

This was all about the Difference between Python vs Java Tutorial.

11. Python Vs Java — Conclusion

So, after all that we’ve discussed here in Python vs Java Tutorial, we come to conclude that both languages have their own benefits. It really is up to you to choose one for your project. While Python is simple and concise, Java is fast and more portable. While Python is dynamically-typed, Java is statically-typed. Both are powerful in their own realms, but we want to know which one you prefer. Furthermore, if you have any query/question, feel free to share with us!