是否有人有一个Java片段可以返回目录中的最新文件(或者是一个简化这种事情的库的知识)?
答案 0 :(得分:56)
返回上次修改时间:
public static File lastFileModified(String dir) {
File fl = new File(dir);
File[] files = fl.listFiles(new FileFilter() {
public boolean accept(File file) {
return file.isFile();
}
});
long lastMod = Long.MIN_VALUE;
File choice = null;
for (File file : files) {
if (file.lastModified() > lastMod) {
choice = file;
lastMod = file.lastModified();
}
}
return choice;
}
答案 1 :(得分:26)
在Java 8中:
Path dir = Paths.get("./path/somewhere"); // specify your directory
Optional<Path> lastFilePath = Files.list(dir) // here we get the stream with full directory listing
.filter(f -> !Files.isDirectory(f)) // exclude subdirectories from listing
.max(Comparator.comparingLong(f -> f.toFile().lastModified())); // finally get the last file using simple comparator by lastModified field
if ( lastFilePath.isPresent() ) // your folder may be empty
{
// do your code here, lastFilePath contains all you need
}
答案 2 :(得分:16)
这对我来说非常好:
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.comparator.LastModifiedFileComparator;
import org.apache.commons.io.filefilter.WildcardFileFilter;
...
/* Get the newest file for a specific extension */
public File getTheNewestFile(String filePath, String ext) {
File theNewestFile = null;
File dir = new File(filePath);
FileFilter fileFilter = new WildcardFileFilter("*." + ext);
File[] files = dir.listFiles(fileFilter);
if (files.length > 0) {
/** The newest file comes first **/
Arrays.sort(files, LastModifiedFileComparator.LASTMODIFIED_REVERSE);
theNewestFile = files[0];
}
return theNewestFile;
}
答案 3 :(得分:1)
类似的东西:
import java.io.File;
import java.util.Arrays;
import java.util.Comparator;
public class Newest {
public static void main(String[] args) {
File dir = new File("C:\\your\\dir");
File [] files = dir.listFiles();
Arrays.sort(files, new Comparator(){
public int compare(Object o1, Object o2) {
return compare( (File)o1, (File)o2);
}
private int compare( File f1, File f2){
long result = f2.lastModified() - f1.lastModified();
if( result > 0 ){
return 1;
} else if( result < 0 ){
return -1;
} else {
return 0;
}
}
});
System.out.println( Arrays.asList(files ));
}
}
答案 4 :(得分:1)
private File getLatestFilefromDir(String dirPath){
File dir = new File(dirPath);
File[] files = dir.listFiles();
if (files == null || files.length == 0) {
return null;
}
File lastModifiedFile = files[0];
for (int i = 1; i < files.length; i++) {
if (lastModifiedFile.lastModified() < files[i].lastModified()) {
lastModifiedFile = files[i];
}
}
return lastModifiedFile;
}
答案 5 :(得分:1)
public File getLastDownloadedFile() {
File choice = null;
try {
File fl = new File("C:/Users/" + System.getProperty("user.name")
+ "/Downloads/");
File[] files = fl.listFiles(new FileFilter() {
public boolean accept(File file) {
return file.isFile();
}
});
//Sleep to download file if not required can be removed
Thread.sleep(30000);
long lastMod = Long.MIN_VALUE;
for (File file : files) {
if (file.lastModified() > lastMod) {
choice = file;
lastMod = file.lastModified();
}
}
} catch (Exception e) {
System.out.println("Exception while getting the last download file :"
+ e.getMessage());
}
System.out.println("The last downloaded file is " + choice.getPath());
System.out.println("The last downloaded file is " + choice.getPath(),true);
return choice;
}
答案 6 :(得分:0)
这是对Jose的代码的小修改,可确保该文件夹中至少包含1个文件。在我的应用程序中,工作很棒!
public static File lastFileModified(String dir) {
File fl = new File(dir);
File choice = null;
if (fl.listFiles().length>0) {
File[] files = fl.listFiles(new FileFilter() {
public boolean accept(File file) {
return file.isFile();
}
});
long lastMod = Long.MIN_VALUE;
for (File file : files) {
if (file.lastModified() > lastMod) {
choice = file;
lastMod = file.lastModified();
}
}
}
return choice;
}
答案 7 :(得分:0)
这将返回最新创建的文件,我这样做是因为在某些情况下创建文件时,它不一定总是具有正确的修改日期。
import java.nio.file.Files;
import java.nio.file.attribute.BasicFileAttributes;
import java.nio.file.attribute.FileTime;
private File lastFileCreated(String dir) {
File fl = new File(dir);
File[] files = fl.listFiles(new FileFilter() {
public boolean accept(File file) {
return true;
}
});
FileTime lastCreated = null;
File choice = null;
for (File file : files) {
BasicFileAttributes attr=null;
try {
attr = Files.readAttributes(file.toPath(), BasicFileAttributes.class);
}catch (Exception e){
System.out.println(e);
}
if(lastCreated ==null)
lastCreated = attr.creationTime();
if (attr!=null&&attr.creationTime().compareTo(lastCreated)==0) {
choice = file;
}
}
return choice;
}
答案 8 :(得分:0)
此代码对我来说很有效:
public String pickLatestFileFromDownloads() {
String currentUsersHomeDir = System.getProperty("user.home");
String downloadFolder = currentUsersHomeDir + File.separator + "Downloads" + File.separator;
File dir = new File(downloadFolder);
File[] files = dir.listFiles();
if (files == null || files.length == 0) {
testLogger.info("There is no file in the folder");
}
File lastModifiedFile = files[0];
for (int i = 1; i < files.length; i++) {
if (lastModifiedFile.lastModified() < files[i].lastModified()) {
lastModifiedFile = files[i];
}
}
String k = lastModifiedFile.toString();
System.out.println(lastModifiedFile);
Path p = Paths.get(k);
String file = p.getFileName().toString();
return file;
}
//PostedBy: saurabh Gupta Aricent-provar