Skip to content

Create performance Issues #5

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
mayanksingh0307 wants to merge 2 commits into
base: main
Choose a base branch
from
Open

Create performance Issues #5

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
b0ea966
Create permonaceIssues
mayanksingh0307 Jun 28, 2024
1c8f874
Rename permonaceIssues to permonaceIssues.java
mayanksingh0307 Jun 28, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
49 changes: 49 additions & 0 deletions permonaceIssues.java
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,49 @@
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

public class PerformanceIssues {
public static void main(String[] args) {
String result = "";
for (int i = 0; i < 10000; i++) {
result += "a";
}
System.out.println(result);
Comment on lines +7 to +11
Copy link
Copy Markdown
Owner Author

@mayanksingh0307 mayanksingh0307 Jun 28, 2024

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Bito Code Review Agent Run #904618 - 06/28/2024, 11:15 am

🔴 High importance
Issue: String concatenation in a loop using the '+' operator is highly inefficient as it creates a new String object on each iteration, leading to significant performance overhead.
Fix: Use 'StringBuilder' for string concatenation in a loop to improve performance.
Code suggestion 
 @@ -7,7 +7,7 @@
      String result = "";
      for (int i = 0; i < 10000; i++) {
          result += "a";
      }
      System.out.println(result);
 +    StringBuilder result = new StringBuilder();
 +    for (int i = 0; i < 10000; i++) {
 +        result.append("a");
 +    }
 +    System.out.println(result.toString());


List<Integer> list = new ArrayList<>();
for (int i = 0; i < 10000; i++) {
list.add(i);
}

for (int i = 0; i < 10000; i++) {
Random random = new Random();
int num = random.nextInt();
System.out.println(num);
}
Comment on lines +18 to +22
Copy link
Copy Markdown
Owner Author

@mayanksingh0307 mayanksingh0307 Jun 28, 2024

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Bito Code Review Agent Run #904618 - 06/28/2024, 11:15 am

🔴 High importance
Issue: Creating a new 'Random' object inside a loop is inefficient and can lead to performance issues. It is better to create a single 'Random' instance and reuse it.
Fix: Create a single 'Random' instance outside the loop and reuse it.
Code suggestion 
 @@ -18,7 +18,7 @@
      for (int i = 0; i < 10000; i++) {
          Random random = new Random();
          int num = random.nextInt();
          System.out.println(num);
      }
 +    Random random = new Random();
 +    for (int i = 0; i < 10000; i++) {
 +        int num = random.nextInt();
 +        System.out.println(num);
 +    }


int count = 0;
for (int i = 2; i < 10000; i++) {
if (isPrime(i)) {
count++;
}
}
System.out.println("Number of primes: " + count);

try (FileReader fileReader = new FileReader("largefile.txt")) {
int ch;
while ((ch = fileReader.read()) != -1) {
System.out.print((char) ch);
}
Comment on lines +32 to +36
Copy link
Copy Markdown
Owner Author

@mayanksingh0307 mayanksingh0307 Jun 28, 2024

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Bito Code Review Agent Run #904618 - 06/28/2024, 11:15 am

🔴 High importance
Issue: Reading a file character by character using 'FileReader' is inefficient for large files. It is better to use a buffered reader to improve performance.
Fix: Use 'BufferedReader' to read the file more efficiently.
Code suggestion 
 @@ -32,7 +32,7 @@
      try (FileReader fileReader = new FileReader("largefile.txt")) {
          int ch;
          while ((ch = fileReader.read()) != -1) {
              System.out.print((char) ch);
          }
      } catch (IOException e) {
          e.printStackTrace();
      }
 +    try (BufferedReader bufferedReader = new BufferedReader(new FileReader("largefile.txt"))) {
 +        String line;
 +        while ((line = bufferedReader.readLine()) != null) {
 +            System.out.println(line);
 +        }
 +    } catch (IOException e) {
 +        e.printStackTrace();
 +    }

} catch (IOException e) {
e.printStackTrace();
}
}

private static boolean isPrime(int n) {
if (n <= 1) return false;
for (int i = 2; i < n; i++) {
if (n % i == 0) return false;
}
return true;
}
}