import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class ThreadPoolExample {
public static void main(String[] args) {
ExecutorService executor = Executors.newFixedThreadPool(5);
for (int i = 0; i < 10; i++) {
Runnable worker = new WorkerThread("" + i);
executor.execute(worker);
}
executor.shutdown();
while (!executor.isTerminated()) {
}
System.out.println("Finished all threads");
}
}
class WorkerThread implements Runnable {
private String message;
public WorkerThread(String s){
this.message=s;
}
public void run() {
System.out.println(Thread.currentThread().getName()+" (Start) message = "+message);
processMessage();
System.out.println(Thread.currentThread().getName()+" (End)");
}
private void processMessage() {
try { Thread.sleep(2000); } catch (InterruptedException e) { e.printStackTrace(); }
}
}
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import java.util.concurrent.TimeUnit;
public class CacheExample {
public static void main(String[] args) {
LoadingCache<String, String> cache = CacheBuilder.newBuilder()
.maximumSize(100)
.expireAfterWrite(10, TimeUnit.MINUTES)
.build(
new CacheLoader<String, String>() {
public String load(String key) throws Exception {
}
}
);
try {
} catch (Exception e) {
e.printStackTrace();
}
}
private static String getFromDatabase(String key) {
System.out.println("Fetching data from database for key: " + key);
// ...
return "value1";
}
}
import java.util.concurrent.CompletableFuture;
public class AsyncExample {
public static void main(String[] args) {
CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> {
return "hello";
});
CompletableFuture<String> newFuture = future.thenApplyAsync(str -> {
return str.toUpperCase();
});
newFuture.thenAccept(result -> {
System.out.println("Result: " + result);
});
}
}
