10 Common Java Errors Beginners Make – And How to Fix Them

*10 Common Java Error Beginners Make-And How to Fix Them*

Java is one of the most popular programming languages, but like every powerful tool, it comes with common beginner mistakes. These errors can be frustrating, but don’t worry — here are the most frequent issues beginners face and how to fix them.

 1. ❌ Missing `main` Method  

Java needs a starting point to run the program.

**Fix:**  

```java

public static void main(String[] args) {

  // your code

}

2. ❌ Case Sensitivity Confusion

System.out.println is not the same as system.out.Println.

Fix: Java is case-sensitive. Use exact class/method names.

3. ❌ Class Name Doesn’t Match File Name

File name and class name must match exactly.

Fix: If the file is HelloWorld.java, your class must be:

java

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public class HelloWorld { ... }

4. ❌ Forgetting Semicolon ;

Statements in Java must end with ;.

Fix: Always check for missing semicolons.

5. ❌ Unreachable Code

Code written after return, break, or continue that never runs.

Fix: Remove or move unreachable code logically.

6. ❌ NullPointerException

Accessing a method or property on a null object.

Fix: Always check if object is not null before use.

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if(obj != null) { obj.doSomething(); }

7. ❌ ArrayIndexOutOfBoundsException

Trying to access index beyond array limits.

Fix: Use correct bounds. Arrays start at 0!

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for(int i = 0; i < array.length; i++) { ... }

8. ❌ Loop Logic Mistake

Using wrong loop condition causes infinite or no loop.

Fix: Double-check your for, while, or do-while logic.

9. ❌ Scanner Skips Input

nextLine() may get skipped after nextInt() or next().

Fix: Consume the leftover newline with an extra nextLine().

10. ❌ Confusing == with .equals()

Using == for string comparison compares reference, not value.

Fix: Use .equals() to compare string content.

java

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if(name.equals("Pavan")) { ... }

✅ Conclusion

These common mistakes are part of every Java developer’s learning journey. The more you code and debug, the better you’ll understand how to avoid them. Happy coding! 😄

✅ तुमचा आवडता Java concept किंवा त्रासदायक error कोणता होता?  

💬 कमेंट करा आणि तुमचं अनुभव शेअर करा!