Setup
- 粘贴是甲骨文示例的修改版本 在
- 程序运行时,如果您现在在
path
目录中创建一个新文件或目录目录,您将看到显示的路径不正确 - 例如,当我运行它时,它将
path
目录中新创建的文件的绝对路径显示为/home/hoagy/test/new_file
,而该文件的实际路径/home/hoagy/test/path/new_file
问题
- 如何获得正确的绝对路径?
法典
package path.question;
import java.nio.file.*;
import static java.nio.file.StandardWatchEventKinds.*;
import static java.nio.file.LinkOption.*;
import java.nio.file.attribute.*;
import java.io.*;
import java.util.*;
public class WatchDir {
private final WatchService watcher;
private final Map<WatchKey,Path> keys;
@SuppressWarnings("unchecked")
static <T> WatchEvent<T> cast(WatchEvent<?> event) {
return (WatchEvent<T>)event;
}
private void register(Path dir) throws IOException {
WatchKey key = dir.register(watcher, ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY);
keys.put(key, dir);
}
WatchDir(Path dir) throws IOException {
this.watcher = FileSystems.getDefault().newWatchService();
this.keys = new HashMap<WatchKey,Path>();
register(dir);
}
void processEvents() {
for (;;) {
WatchKey key;
try { key = watcher.take(); }
catch (InterruptedException x) { return; }
Path dir = keys.get(key);
if (dir == null) {
continue;
}
for (WatchEvent<?> event: key.pollEvents()) {
WatchEvent.Kind kind = event.kind();
if (kind == OVERFLOW) { continue; }
WatchEvent<Path> ev = cast(event);
Path name = ev.context();
Path child = dir.resolve(name);
System.out.println("Full path: " + name.toAbsolutePath().toString());
}
key.reset();
}
}
public static void main(String[] args) throws IOException {
Path dir = Paths.get("./path");
new WatchDir(dir).processEvents();
}
}
替换 :
//prints the "absolute path" of the name of the file
System.out.println("Full path: " + name.toAbsolutePath().toString());
跟
//prints the "absolute path" of the "child"
System.out.println("child " + child.toAbsolutePath().toString());