이미지를 byte[]로 변환import java.io.File;import java.io.FileInputStream;import java.io.IOException;public byte[] readImage(String filePath) throws IOException { File file = new File(filePath); FileInputStream fis = new FileInputStream(file); byte[] imageBytes = new byte[(int) file.length()]; fis.read(imageBytes); fis.close(); return imageBytes;}mybatis 사용하지 않고, BLOB 저장import java.sql..

데이터XML SELECT id, name, age FROM users WHERE name IN #{name} Javaimport java.util.HashMap;import java.util.List;import java.util.Map;public class UserService { private final UserMapper userMapper; public UserService(UserMapper userMapper) { this.userMapper = userMapper; } public List> getUsersByNames(List nameList) { // Create a parameter map for ..

import java.time.LocalDate;import java.time.format.DateTimeFormatter;public class DateExample { public static void main(String[] args) { LocalDate today = LocalDate.now(); DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMdd"); String formattedDate = today.format(formatter); System.out.println("Today's date in yyyymmdd format: " + formattedDate); }}

row.get("name")에서 형변환을 잘해줘야 함import java.util.ArrayList;import java.util.List;import java.util.Map;import java.util.stream.Collectors;public class ColumnExtractor { public static void main(String[] args) { List> data = new ArrayList(); data.add(Map.of("id", 1, "name", "Alice", "age", 25)); data.add(Map.of("id", 2, "name", "Bob", "age", 30)); data.add(Map.of("id", 3..

중복 데이터 삭제(차집합)import java.util.ArrayList;import java.util.List;public class RemoveDuplicates { public static void main(String[] args) { List list1 = new ArrayList(List.of("apple", "banana", "orange", "grape")); List list2 = new ArrayList(List.of("banana", "kiwi", "grape", "melon")); // Remove duplicates from list1 that are in list2 list1.removeAll(list2); //..

public class FileUtils { public static List getFiles(String directory) { try(Stream filePaths = Files.walk(Paths.get(directory))) { return filePaths .filter(Files::isRegularFile) .collect(Collectors.toList()); } catch(IOException e) { e.printStackTrace(); return List.of(); } }}public class Main { public static void main(String[] args) { List files = FileUtils.getFiles(..