我正在尝试为用户登录的每个用户名创建一个文件夹。目前我有
private String destination = "C:/Users/Richard/printing~subversion/fileupload/web/WEB-INF/uploaded/"; // main location for uploads
File theFile = new File(destination + username); // will create a sub folder for each user
但是File theFile位不会为用户名创建新文件夹。我该怎么做？
我试过了
private String destination;
public void File()
{
destination = "C:/Users/Richard/printing~subversion/fileupload/web/WEB-INF/uploaded/"; // main location for uploads
File theFile = new File(destination + username); // will create a sub folder for each user (currently does not work, below hopefully is a solution)
theFile.mkdirs();
}
但是我需要在程序的后面使用目的地，我该怎么做？
这是我的整个代码：
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package richard.fileupload;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.annotation.PostConstruct;
import javax.faces.application.FacesMessage;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
import javax.faces.application.FacesMessage;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ViewScoped;
import javax.faces.context.FacesContext;
import java.io.File;
import org.primefaces.event.FileUploadEvent;
@ViewScoped
@ManagedBean(name = "fileUploadController")
public class FileUploadController {
/*
public void handleFileUpload(FileUploadEvent event) {
System.out.println("called");
FacesMessage msg = new FacesMessage("Succesful", event.getFile().getFileName() + " is uploaded.");
FacesContext.getCurrentInstance().addMessage(null, msg);
}
}
*/
private String username;
private String destination;
@PostConstruct
public void init() {
System.out.println("called get username");
username = FacesContext.getCurrentInstance().getExternalContext().getRemoteUser();
}
public void File() {
destination = "C:/Users/Richard/printing~subversion/fileupload/web/WEB-INF/uploaded/"; // main location for uploads
File theFile = new File(destination + username); // will create a sub folder for each user (currently does not work, below hopefully is a solution)
theFile.mkdirs();
}
public File getDirectory(String destination, String username) {
System.out.println("called get directory");
// currently not working, is not calling the username or destination
//set the user directory from the destinarion and the logged user name
File directory = new File(destination, username);
//check if the location exists
if (!directory.exists()) {
//let's try to create it
try {
directory.mkdir();
} catch (SecurityException secEx) {
//handle the exception
secEx.printStackTrace(System.out);
directory = null;
}
}
return directory;
}
public void handleFileUpload(FileUploadEvent event) {
System.out.println("called handle file");
FacesMessage msg = new FacesMessage("Succesful", event.getFile().getFileName() + " is uploaded."); //Displays to user on the webpage
FacesContext.getCurrentInstance().addMessage(null, msg);
try {
copyFile(event.getFile().getFileName(), event.getFile().getInputstream());
} catch (IOException e) {
//handle the exception
e.printStackTrace();
}
}
public void copyFile(String fileName, InputStream in) {
try {
// write the inputStream to a FileOutputStream
OutputStream out = new FileOutputStream(new File(destination + fileName)); // cannot find path when adding username atm
System.out.println("Called CopyFile"); //testing
System.out.println(destination + fileName);
int read = 0;
byte[] bytes = new byte[1024];
while ((read = in.read(bytes)) != -1) {
out.write(bytes, 0, read);
}
in.close();
out.flush();
out.close();
//make sure new file is created, (displays in glassfish server console not to end user)
System.out.println("New file created!");//testing
} catch (IOException e) {
e.printStackTrace();
FacesMessage error = new FacesMessage("The files were not uploaded!");
FacesContext.getCurrentInstance().addMessage(null, error);
}
}
}
最终编辑（希望如此）
public void copyFile(String fileName, InputStream in) {
try {
destination = "C:/Users/Richard/printing~subversion/fileupload/web/WEB-INF/uploaded/"; // main location for uploads
File theFile = new File(destination + "/" + username);
theFile.mkdirs();// will create a sub folder for each user (currently does not work, below hopefully is a solution) (DOES NOW WORK)
System.out.println("Completed File");
// write the inputStream to a FileOutputStream
OutputStream out = new FileOutputStream(new File(destination + fileName)); // cannot find path when adding username atm
System.out.println("Called CopyFile"); //testing
System.out.println(destination + fileName);
int read = 0;
byte[] bytes = new byte[1024];
while ((read = in.read(bytes)) != -1) {
out.write(bytes, 0, read);
}
in.close();
out.flush();
out.close();
//make sure new file is created, (displays in glassfish server console not to end user)
System.out.println("New file created!");//testing
} catch (IOException e) {
e.printStackTrace();
FacesMessage error = new FacesMessage("The files were not uploaded!");
FacesContext.getCurrentInstance().addMessage(null, error);
}
}
}
我怎样才能打印出新目标并在以后使用它，因为当前它会创建新文件夹但没有选择使用它
编辑也解决了这个问题：
NewDestination = "C:/Users/Richard/printing~subversion/fileupload/web/WEB-INF/uploaded/" + username;
添加了上面的代码，现在一切正常
您必须实际调用某个方法来创建目录。仅创建 file 对象不会在文件系统上创建相应的文件或目录。
您可以使用File#mkdirs()方法创建目录：-
theFile.mkdirs();
File#mkdir()和File#mkdirs()之间的区别在于，如果中间目录不存在，后者将创建任何中间目录。
如果在
创建/编辑文件时不存在中间文件夹，请使用此代码 spinet 创建中间文件夹：
File outFile = new File("/dir1/dir2/dir3/test.file");
outFile.getParentFile().mkdirs();
outFile.createNewFile();
Benoit Blanchon 的一个很好的 Java 7+ 答案可以在这里找到：
在 Java 7 中，您可以使用
Files.createDirectories().例如：
Files.createDirectories(Paths.get("/path/to/directory"));
如果你有一个大型的堆叠、不存在的目录层次结构，你必须首先调用Files.createDirectories(..) 。例如，在 Kotlin 中，它可能看起来像这样：
fun File.createFileWithParentDirectories() {
if(this.exists())return
val parent = this.parentFile
if(!parent.exists()) Files.createDirectories(parent.toPath())
this.createNewFile()
}