package wwww;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.RecursiveTask;
import java.util.concurrent.TimeUnit;
public class FolderProcessor extends RecursiveTask<List<String>> {
private static final long serialVersionUID = -590727688578356028L;
private String path;
private String extension;
public static void main(String[] args) {
ForkJoinPool pool = new ForkJoinPool(12);
// 创建3个FolderProcessor任务。用不同的文件夹路径初始化每个任务。
FolderProcessor system = new FolderProcessor("C:\\", "txt");
FolderProcessor apps = new FolderProcessor("D:\\", "txt");
FolderProcessor documents = new FolderProcessor("E:\\", "txt");
// 在池中使用execute()方法执行这3个任务。
pool.execute(system);
pool.execute(apps);
pool.execute(documents);
// 将关于池每秒的状态信息写入到控制台，直到这3个任务完成它们的执行。
do {
System.out.printf("******************************************\n");
System.out.printf("Main: Parallelism: %d\n", pool.getParallelism());
System.out.printf("Main: Active Threads: %d\n", pool.getActiveThreadCount());
System.out.printf("Main: Task Count: %d\n", pool.getQueuedTaskCount());
System.out.printf("Main: Steal Count: %d\n", pool.getStealCount());
System.out.printf("******************************************\n");
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
} while ((!system.isDone()) || (!apps.isDone())
|| (!documents.isDone()));
// 使用shutdown()方法关闭ForkJoinPool。
pool.shutdown();
// 将每个任务产生的结果数量写入到控制台。
List<String> results;
results = system.join();
System.out.printf("System: %d files found.\n", results.size());
for (String string : results) {
System.out.println(string);
}
results = apps.join();
System.out.printf("Apps: %d files found.\n", results.size());
for (String string : results) {
System.out.println(string);
}
results = documents.join();
System.out.printf("Documents: %d files found.\n", results.size());
for (String string : results) {
System.out.println(string);
}
}
public FolderProcessor(String path, String extension) {
this.path = path;
this.extension = extension;
}
@Override
protected List<String> compute() {
List<String> list = new ArrayList<String>();
List<FolderProcessor> tasks = new ArrayList<FolderProcessor>();
File file = new File(path);
File content[] = file.listFiles();
if (content != null) {
for (int i = 0; i < content.length; i++) {
if (content[i].isDirectory()) {
FolderProcessor task = new FolderProcessor(
content[i].getAbsolutePath(), extension);
task.fork();
tasks.add(task);
} else {
if (checkFile(content[i].getName())) {
list.add(content[i].getAbsolutePath());
}
}
}
/*if (tasks.size() > 50) {
System.out.printf("%s: %d tasks ran.\n",
file.getAbsolutePath(), tasks.size());
}*/
addResultsFromTasks(list, tasks);
}
return list;
}
private void addResultsFromTasks(List<String> list,
List<FolderProcessor> tasks) {
for (FolderProcessor item : tasks) {
list.addAll(item.join());
}
}
private boolean checkFile(String name) {
return name.endsWith(extension);
}
}