JAVA如何获取上传后的文件名

同意楼上的分析，另外我想提个建议，代码为了便于阅读可以试着分步骤写。

就先定义filename和filepath，然后你在纤禅后续的 *** 作中想要图片出现在设知稿定的某一区域中

就可以直接使用毁猛尘filename，将要上传的文件名是 its.getIPTimeStampRand()+"."+item.getName().split("\\.")[1]

基本上面几位都说啦。。。

只说一点就是注意null和空的处理

import java.io.File

import java.util.HashSet

import java.util.Set

public class ReadFileSample {

private static final String PATH = "C:\\TEST"

private static final char SEPARATOR = '_'

public static void main(String[] args) {

Set<String>fileSet = new HashSet<String>()

File[] files = new File(PATH).listFiles()

for (File file : files) {

// 由于Set的元素是不重复世桥的，不用做重复判断，直接拦返渗放入

fileSet.add(getPrefixFileName(file.getName()))

}

/简脊/ 由于Set允许null，所以要去除

fileSet.remove(null)

// 打印出Set的内容（需要的数据）

System.out.println(fileSet)

}

private static String getPrefixFileName(String fileName) {

if (fileName == null || fileName.length() == 0) {

return null

}

int index = fileName.indexOf(SEPARATOR)

if (index <0) {

// 不含SEPARATOR的文件名

return null

}

// 从文件名开头到SEPARATOR的位置，截取

return fileName.substring(0, index)

}

}

1.文件上传

package com.whw.action

import java.io.File

import javax.servlet.ServletContext

import org.apache.commons.io.FileUtils

import org.apache.struts2.util.ServletContextAware

import com.opensymphony.xwork2.ActionSupport

public class UploadAction extends ActionSupport implements ServletContextAware {

private static final long serialVersionUID = 1L

private File upload// 实际上传文件

private String uploadContentType// 文件的内容类型

private String uploadFileName// 文件 名称

private String fileCaption/备隐昌/ 上传文携铅件时的备注

private ServletContext context

public String execute() throws Exception {

try {

String targetDirectory = context.getRealPath("/upload")

String targetFileName = fileCaption+uploadFileName

File target = new File(targetDirectory, targetFileName)

FileUtils.copyFile(upload, target)

setUploadFileName(target.getPath())//保存文件的存仿扒放路径

} catch (Exception e) {

addActionError(e.getMessage())

return INPUT

}

return SUCCESS

}

public String getFileCaption() {

return fileCaption

}

public void setFileCaption(String fileCaption) {

this.fileCaption = fileCaption

}

public File getUpload() {

return upload

}

public void setUpload(File upload) {

this.upload = upload

}

public String getUploadContentType() {

return uploadContentType

}

public void setUploadContentType(String uploadContentType) {

this.uploadContentType = uploadContentType

}

public String getUploadFileName() {

return uploadFileName

}

public void setUploadFileName(String uploadFileName) {

this.uploadFileName = uploadFileName

}

public void setServletContext(ServletContext context) {

this.context = context

}

}

2.读取文件夹下的文件

package sample

import java.io.*

public class CopyFileStream{// copy one file to another file

public static void main(String args[]) {

FileInputStream fromFile=null

FileOutputStream toFile=null

try{

//生成两个已有byte文件的 流对象。

fromFile=new FileInputStream(args[0]) // get file name from console

toFile=new FileOutputStream(args[1]) // get file name from console

} catch (FileNotFoundException e){

System.err.println("File could not be found")

return//缺文件名输入，抛异常，返回。

} catch (IOException e){

System.err.println("File could not be copied ")

return

} catch (ArrayIndexOutOfBoundsException e){

System.err.println("Usage: CopyByteFile from-file to-file")

return

}

try {

fromFile.close() // close InputStream

toFile.close() // close OutputStream

}catch (IOException e){

System.err.println("Error closing File.")

}

}

}

File类下的exists()方法是判断文件是否存在返回值是boolean

希望是你需要的。

---