Loading...
More Java Posts
import javax.mail.*;import javax.mail.internet.*;import java.util.*;public void postMail( String recipients[ ], String subject, String message , String from) throws MessagingException{boolean debug = false;//Set the host smtp addressProperties props = new Properties();props.put("mail.smtp.host", "smtp.example.com");// create some properties and get the default SessionSession session = Session.getDefaultInstance(props, null);session.setDebug(debug);// create a messageMessage msg = new MimeMessage(session);// set the from and to addressInternetAddress addressFrom = new InternetAddress(from);msg.setFrom(addressFrom);InternetAddress[] addressTo = new InternetAddress[recipients.length];for (int i = 0; i < recipients.length; i++){addressTo[i] = new InternetAddress(recipients[i]);}msg.setRecipients(Message.RecipientType.TO, addressTo);// Optional : You can also set your custom headers in the Email if you Wantmsg.addHeader("MyHeaderName", "myHeaderValue");// Setting the Subject and Content Typemsg.setSubject(subject);msg.setContent(message, "text/plain");Transport.send(msg);}
public class Factorial{public static void main(String[] args){ final int NUM_FACTS = 100;for(int i = 0; i < NUM_FACTS; i++)System.out.println( i + "! is " + factorial(i));}public static int factorial(int n){ int result = 1;for(int i = 2; i <= n; i++)result *= i;return result;}}
import static java.lang.System.*;import java.util.Arrays;public class MergeSort{private static int passCount;public static void mergeSort(int[] list){passCount=0;mergeSort(list, 0, list.length);}private static void mergeSort(int[] list, int front, int back) //O( Log N ){int mid = (front+back)/2;if(mid==front) return;mergeSort(list, front, mid);mergeSort(list, mid, back);merge(list, front, back);}private static void merge(int[] list, int front, int back) //O(N){int dif = back-front;int[] temp = new int[dif];int beg = front, mid = (front+back)/2;int saveMid = mid;int spot = 0;while(beg < saveMid && mid < back) {if(list[beg] < list[mid]) {temp[spot++] = list[beg++];} else {temp[spot++] = list[mid++];}}while(beg < saveMid)temp[spot++] = list[beg++];while(mid < back)temp[spot++] = list[mid++];for(int i = 0; i < back-front; i++) {list[front+i] = temp[i];}System.out.println("pass " + passCount++ + " " + Arrays.toString(list) + "\n");}public static void main(String args[]){mergeSort(new Comparable[]{ 9, 5, 3, 2 });System.out.println("\n");mergeSort(new Comparable[]{ 19, 52, 3, 2, 7, 21 });System.out.println("\n");mergeSort(new Comparable[]{ 68, 66, 11, 2, 42, 31});System.out.println("\n");}}
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);elsewordCount.put(word, wordCount.get(word) + 1);}// show resultsfor(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.");}}}
import java.util.Arrays;public class LongestIncreasingSubsequence {public int lengthOfLIS(int[] nums) {if (nums.length == 0) {return 0;}int[] dp = new int[nums.length];Arrays.fill(dp, 1); // Initialize all elements in dp array to 1, as each element itself is a valid subsequence of length 1.int maxLength = 1; // Initialize the maximum length to 1, considering a single element as the sequence.for (int i = 1; i < nums.length; i++) {for (int j = 0; j < i; j++) {if (nums[i] > nums[j]) {dp[i] = Math.max(dp[i], dp[j] + 1); // If nums[i] is greater than nums[j], update the longest subsequence length ending at i.}}maxLength = Math.max(maxLength, dp[i]); // Update the maximum length if needed.}return maxLength;}public static void main(String[] args) {LongestIncreasingSubsequence lis = new LongestIncreasingSubsequence();int[] nums = {10, 9, 2, 5, 3, 7, 101, 18};int result = lis.lengthOfLIS(nums);System.out.println("Length of the Longest Increasing Subsequence: " + result); // Output: 4}}
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 hereSystem.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 userif (id < 0) {throw new Exception("Invalid user id");}// Return the user objectreturn 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;}}