public static String addBinary(){
 // The two input Strings, containing the binary representation of the two values:
    String input0 = "1010";
    String input1 = "10";

    // Use as radix 2 because it's binary    
    int number0 = Integer.parseInt(input0, 2);
    int number1 = Integer.parseInt(input1, 2);

    int sum = number0 + number1;
    return Integer.toBinaryString(sum); //returns the answer as a binary value;
}

//sample code to write 100 random ints to a file, 1 per line

import java.io.PrintStream;
import java.io.IOException;
import java.io.File;

import java.util.Random;

public class WriteToFile {
    public static void main(String[] args) {
        try {
            PrintStream writer = new PrintStream(new File("randInts.txt"));
            Random r = new Random();
            final int LIMIT = 100;

            for (int i = 0; i < LIMIT; i++) {
                writer.println(r.nextInt());
            }
            writer.close();
        } catch (IOException e) {
            System.out.println("An error occured while trying to write to the file");
        }
    }
}

import java.util.Arrays;

public class Main {
    public static int findMinNonCreatableSum(int[] coins) {
        // Sort the array
        Arrays.sort(coins);
        
        // Initialize max creatable sum
        int maxCreatable = 0;
        
        // Iterate through coins
        for (int coin : coins) {
            // If current coin is greater than maxCreatable + 1,
            // we found our answer
            if (coin > maxCreatable + 1) {
                return maxCreatable + 1;
            }
            // Add current coin to maxCreatable
            maxCreatable += coin;
        }
        
        // If we can create all sums up to maxCreatable,
        // the answer is maxCreatable + 1
        return maxCreatable + 1;
    }

    public static void main(String[] args) {
        int[] coins = {2, 9, 1, 2, 7};
        int result = findMinNonCreatableSum(coins);
        System.out.println("Smallest sum that cannot be created: " + result);
    }
}

public class UserService {

  private UserRepository userRepository;

  public UserService(UserRepository userRepository) {
    this.userRepository = userRepository;
  }

  public User getUserById(long id) {
    try {
      return userRepository.getUserById(id);
    } catch (Exception e) {
      // Log the exception here
      System.out.println("An error occurred while fetching the user: " + e.getMessage());
      return null;
    }
  }
}

public class UserRepository {

  public User getUserById(long id) throws Exception {
    // Database query to fetch the user
    if (id < 0) {
      throw new Exception("Invalid user id");
    }
    // Return the user object
    return new User(id, "John Doe");
  }
}

public class User {

  private long id;
  private String name;

  public User(long id, String name) {
    this.id = id;
    this.name = name;
  }

  public long getId() {
    return id;
  }

  public String getName() {
    return name;
  }
}

import java.io.File;
import java.io.IOException;
import java.util.Map;
import java.util.Scanner;
import java.util.TreeMap;

public class SimpleWordCounter {
    
    public static void main(String[] args) {
        try {
            File f = new File("ciaFactBook2008.txt");
            Scanner sc;
            sc = new Scanner(f);
            // sc.useDelimiter("[^a-zA-Z']+");
            Map<String, Integer> wordCount = new TreeMap<String, Integer>();
            while(sc.hasNext()) {
                String word = sc.next();
                if(!wordCount.containsKey(word))
                    wordCount.put(word, 1);
                else
                    wordCount.put(word, wordCount.get(word) + 1);
            }
            
            // show results
            for(String word : wordCount.keySet())
                System.out.println(word + " " + wordCount.get(word));
            System.out.println(wordCount.size());
        }
        catch(IOException e) {
            System.out.println("Unable to read from file.");
        }
    }
}