我正在尝试实现程序来压缩和解压缩文件。我想要做的就是压缩一个名为 fileName.zip 的 file (fileName.fileExtension) 并在解压缩时再次将其更改为 fileName.fileExtension.
这就是我过去重命名文件或更改其扩展名的方式。
public static void modify(File file)
{
int index = file.getName().lastIndexOf(".");
//print filename
//System.out.println(file.getName().substring(0, index));
//print extension
//System.out.println(file.getName().substring(index));
String ext = file.getName().substring(index);
//use file.renameTo() to rename the file
file.renameTo(new File("Newname"+ext));
}
edit:John 的方法重命名文件(保留扩展名)。要更改扩展名,请执行以下操作:
public static File changeExtension(File f, String newExtension) {
int i = f.getName().lastIndexOf('.');
String name = f.getName().substring(0,i);
return new File(f.getParent(), name + newExtension);
}
这只会将最后一个扩展名更改为文件名,即
.gz
的archive.tar.gz
部分。因此它适用于 Linux 隐藏文件,其名称以 .
开头
这是非常安全的,因为如果 getParent()
返回 null
(即在父级是系统根的情况下)它被“强制转换”为一个空字符串,因为首先评估 File 构造函数的整个参数。
你会得到一个有趣的输出的唯一情况是,如果你传入一个代表系统根本身的文件,在这种情况下,
null
被添加到路径字符串的其余部分之前。
尝试:
File file = new File("fileName.zip"); // handler to your ZIP file
File file2 = new File("fileName.fileExtension"); // destination dir of your file
boolean success = file.renameTo(file2);
if (success) {
// File has been renamed
}
我会在更改前检查文件是否有扩展名。下面的解决方案也适用于没有扩展名或多个扩展名的文件
public File changeExtension(File file, String extension) {
String filename = file.getName();
if (filename.contains(".")) {
filename = filename.substring(0, filename.lastIndexOf('.'));
}
filename += "." + extension;
file.renameTo(new File(file.getParentFile(), filename));
return file;
}
@Test
public void test() {
assertThat(changeExtension(new File("C:/a/aaa.bbb.ccc"), "txt"),
is(new File("C:/a/aaa.bbb.txt")));
assertThat(changeExtension(new File("C:/a/test"), "txt"),
is(new File("C:/a/test.txt")));
}
按照与 @hsz 相同的逻辑,而是简单地使用替换:
File file = new File("fileName.fileExtension"); // creating object of File
String str = file.getPath().replace(".fileExtension", ".zip"); // replacing extension to another
file.renameTo(new File(str));
我想避免新扩展恰好出现在路径或文件名本身中。我喜欢 java.nio 和 apache StringFilenameUtils 的组合。
public void changeExtension(Path file, String extension) throws IOException {
String newFilename = FilenameUtils.removeExtension(file.toString()) + EXTENSION_SEPARATOR_STR + extension;
Files.move(file, Paths.get(newFilename, StandardCopyOption.REPLACE_EXISTING));
}
如果您使用的是 Kotlin,您可以使用
file
对象的这个属性:
file.nameWithoutExtension + "extension"
FilenameUtils.getFullPathNoEndSeparator(doc.getDocLoc()) + "/" +
FilenameUtils.getBaseName(doc.getDocLoc()) + ".xml"
大约 4 个月前,我的朋友正在用 Java 开发一个拉链,我从他那里得到了这段代码。
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
public class ZipFiles {
List<String> filesListInDir = new ArrayList<String>();
public static void main(String[] args) {
File file = new File("/Users/pankaj/sitemap.xml");
String zipFileName = "/Users/pankaj/sitemap.zip";
File dir = new File("/Users/pankaj/tmp");
String zipDirName = "/Users/pankaj/tmp.zip";
zipSingleFile(file, zipFileName);
ZipFiles zipFiles = new ZipFiles();
zipFiles.zipDirectory(dir, zipDirName);
}
/**
* This method zips the directory
* @param dir
* @param zipDirName
*/
private void zipDirectory(File dir, String zipDirName) {
try {
populateFilesList(dir);
//now zip files one by one
//create ZipOutputStream to write to the zip file
FileOutputStream fos = new FileOutputStream(zipDirName);
ZipOutputStream zos = new ZipOutputStream(fos);
for(String filePath : filesListInDir){
System.out.println("Zipping "+filePath);
//for ZipEntry we need to keep only relative file path, so we used substring on absolute path
ZipEntry ze = new ZipEntry(filePath.substring(dir.getAbsolutePath().length()+1, filePath.length()));
zos.putNextEntry(ze);
//read the file and write to ZipOutputStream
FileInputStream fis = new FileInputStream(filePath);
byte[] buffer = new byte[1024];
int len;
while ((len = fis.read(buffer)) > 0) {
zos.write(buffer, 0, len);
}
zos.closeEntry();
fis.close();
}
zos.close();
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* This method populates all the files in a directory to a List
* @param dir
* @throws IOException
*/
private void populateFilesList(File dir) throws IOException {
File[] files = dir.listFiles();
for(File file : files){
if(file.isFile())
filesListInDir.add(file.getAbsolutePath());
else
populateFilesList(file);
}
}
/**
* This method compresses the single file to zip format
* @param file
* @param zipFileName
*/
private static void zipSingleFile(File file, String zipFileName) {
try {
//create ZipOutputStream to write to the zip file
FileOutputStream fos = new FileOutputStream(zipFileName);
ZipOutputStream zos = new ZipOutputStream(fos);
//add a new Zip Entry to the ZipOutputStream
ZipEntry ze = new ZipEntry(file.getName());
zos.putNextEntry(ze);
//read the file and write to ZipOutputStream
FileInputStream fis = new FileInputStream(file);
byte[] buffer = new byte[1024];
int len;
while ((len = fis.read(buffer)) > 0) {
zos.write(buffer, 0, len);
}
//Close the zip entry to write to zip file
zos.closeEntry();
//Close resources
zos.close();
fis.close();
fos.close();
System.out.println(file.getCanonicalPath()+" is zipped to "+zipFileName);
} catch (IOException e) {
e.printStackTrace();
}
}
}
我没有亲自尝试过,但他和我的其他一些朋友告诉我它有效。