Java to Python

With the support of auto-completion and AI, syntax has become less critical, but you still need to understand the code.

I have compiled a comparison of Java and Python code to reinforce your understanding, as familiarity comes with exposure.

1. Declaration and Output

Java:

public class Main {
    public static void main(String[] args) {
        int x = 10;
        String name = "Alice";
        System.out.println("Hello, " + name + ", x=" + x);
    }
}

Python:

x = 10
name = "Alice"
print(f"Hello, {name}, x={x}")

2. Conditional Statements

Java:

if (x > 5) {
    System.out.println("Big");
} else {
    System.out.println("Small");
}

Python:

if x > 5:
    print("Big")
else:
    print("Small")

3. Arrays

Java:

List<Integer> nums = new ArrayList<>();
nums.add(1); // Add element
nums.add(2);
System.out.println(nums.get(0));

Python:

nums = [1, 2]
nums.append(3) # Add element
print(nums[0])

4. Loops

Java:

for (int i = 0; i < 5; i++) {
    System.out.println(i);
}

Python:

for i in range(5):
    print(i)

5. Functions

Java:

int add(int a, int b) {
    return a + b;
}

Python:

def add(a, b):
    return a + b

6. Dictionaries

Java:

Map<String, Integer> ages = new HashMap<>();
ages.put("Alice", 20);
System.out.println(ages.get("Alice"));

Python:

ages = {"Alice": 20} # Similar to JSON
print(ages["Alice"])  # A bit odd

7. Objects

Java:

public class Person {
    private String name;
    public Person(String name) { this.name = name; }
    public void sayHi() { System.out.println("Hi " + name); }
}
Person p = new Person("Tom");
p.sayHi();

Python:

class Person:
    def __init__(self, name): # Constructor
        self.name = name  # Equivalent to this.name
    def say_hi(self):
        print("Hi", self.name)

p = Person("Tom")
p.say_hi()