import java.util.ArrayList;
import java.util.List;
public class CollectionExample {
public static void main(String[] args) {
List<String> names = new ArrayList<>();
names.add("Alice");
names.add("Bob");
names.add("Charlie");
for (String name : names) {
System.out.println(name);
}
}
}
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class ConcurrencyExample {
public static void main(String[] args) {
ExecutorService executor = Executors.newFixedThreadPool(5);
for (int i = 0; i < 10; i++) {
final int taskNumber = i;
executor.execute(() -> {
System.out.println("Running task number: " + taskNumber);
});
}
executor.shutdown();
}
}
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
public class IOExample {
public static void main(String[] args) {
try (BufferedReader reader = new BufferedReader(new FileReader("input.txt"));
FileWriter writer = new FileWriter("output.txt")) {
String line;
while ((line = reader.readLine()) != null) {
writer.write(line);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
public class ExceptionExample {
public static void main(String[] args) {
try {
int result = divide(10, 0);
System.out.println("Result: " + result);
} catch (ArithmeticException e) {
System.out.println("Error: " + e.getMessage());
}
}
public static int divide(int dividend, int divisor) {
return dividend / divisor;
}
}
