背景
把文件压里头
把文件夹压里头
相关参考
我之前的一个文章,文件递归复制思路link
思路
如果把单单一个文件压缩,那么恭喜你,不用看这个文章了,因为百度一搜就有不错的答案。
本文主要介绍,如果把整个文件夹压缩成一个文件,如何把一个压缩文件,解压出来
开发
因为是安卓原生api,这里就不作环境介绍了。
文末有全部代码!!!
文件夹压缩
首先,外部调用这个方法,就是传入一个需要压缩的文件夹的路径即可。例如/ddd/ddd/
这种,那么,代码就会进行一个判断:
(1)如果是目录,则创建目录
(2)如果是文件,那就搞里头
涉及的操作对象:ZipEntry,ZipOutputStream
注意的点:
(1)源头目录的层级,和压缩文件目录的层级,是不一样的!!!
(2)如果是目录,同样的,也需要在压缩文件中创建,保持源头的目录层级,和压缩文件的目录层级一致!!!
关键api:
zipOutputSteam.putNextEntry(zipEntry);
这个entry,就是你放入压缩文件中的操作对象,可以是文件,也可以是目录!!
核心代码如下:
try {
File file = new File(folderString + fileString);
if (file.isFile()) {
ZipEntry zipEntry = new ZipEntry(fileString);
inputStream = new FileInputStream(file);
zipOutputSteam.putNextEntry(zipEntry);
int len;
byte[] buffer = new byte[4096];
while ((len = inputStream.read(buffer)) != -1) {
zipOutputSteam.write(buffer, 0, len);
}
zipOutputSteam.closeEntry();
} else {
//文件夹
//无论有没有子文件,都进行文件夹的创建
ZipEntry zipEntry = new ZipEntry(fileString + File.separator);
zipOutputSteam.putNextEntry(zipEntry);
zipOutputSteam.closeEntry();
String[] childFileList = file.list();
//没有子文件和压缩
//子文件和递归
if (childFileList != null) {
for (int i = 0; i < childFileList.length; i++) {
File cacheFile = new File(childFileList[i]);
String folderResult = folderString;
ZipFiles(folderResult, fileString + File.separator + cacheFile.getName(), zipOutputSteam);
}
}
}
}
其实递归的逻辑,和文件夹递归复制,是一样的,区别就是,压缩文件将会多一个ZipEntry操作的流程。
解压
对于解压,这里同样,也是判断是目录,还是文件,
若是目录,则创建,若是文件,则通过ZipFile.getInputStream后,进行文件流本地生成。
核心代码如下:
private static void unZipChild(ZipFile zipFile, ZipEntry zipEntry, String targetFolder) {
try {
if (zipEntry.isDirectory()) {
String targetDir = targetFolder + zipEntry.getName();
new File(targetDir).mkdirs();
} else {
InputStream inputStream = zipFile.getInputStream(zipEntry);
FileOutputStream outputStream = new FileOutputStream(new File(targetFolder, zipEntry.getName()));
byte[] buffer = new byte[1024];
int length;
while ((length = inputStream.read(buffer)) > 0) {
outputStream.write(buffer, 0, length);
}
outputStream.close();
inputStream.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
上面是文件夹压缩和解压的全部思路,下面放出所有的相关代码
public class ZipUtils {
/**
* 压缩文件
*
* @param folderString
* @param fileString
* @param zipOutputSteam
* @throws Exception
*/
private static void ZipFiles(String folderString, String fileString, ZipOutputStream zipOutputSteam) throws Exception {
if (zipOutputSteam == null)
return;
FileInputStream inputStream = null;
try {
File file = new File(folderString + fileString);
if (file.isFile()) {
ZipEntry zipEntry = new ZipEntry(fileString);
inputStream = new FileInputStream(file);
zipOutputSteam.putNextEntry(zipEntry);
int len;
byte[] buffer = new byte[4096];
while ((len = inputStream.read(buffer)) != -1) {
zipOutputSteam.write(buffer, 0, len);
}
zipOutputSteam.closeEntry();
} else {
//文件夹
//无论有没有子文件,都进行文件夹的创建
ZipEntry zipEntry = new ZipEntry(fileString + File.separator);
zipOutputSteam.putNextEntry(zipEntry);
zipOutputSteam.closeEntry();
String[] childFileList = file.list();
//没有子文件和压缩
//子文件和递归
if (childFileList != null) {
for (int i = 0; i < childFileList.length; i++) {
File cacheFile = new File(childFileList[i]);
String folderResult = folderString;
ZipFiles(folderResult, fileString + File.separator + cacheFile.getName(), zipOutputSteam);
}
}
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
}
// 递归删除目录及其子目录和文件
public static boolean deleteDirectory(File dir) {
if (dir.isDirectory()) {
String[] children = dir.list();
for (String child : children) {
boolean success = deleteDirectory(new File(dir, child));
if (!success) {
return false;
}
}
}
return dir.delete();
}
private static void unZipChild(ZipFile zipFile, ZipEntry zipEntry, String targetFolder) {
try {
if (zipEntry.isDirectory()) {
String targetDir = targetFolder + zipEntry.getName();
new File(targetDir).mkdirs();
} else {
InputStream inputStream = zipFile.getInputStream(zipEntry);
FileOutputStream outputStream = new FileOutputStream(new File(targetFolder, zipEntry.getName()));
byte[] buffer = new byte[1024];
int length;
while ((length = inputStream.read(buffer)) > 0) {
outputStream.write(buffer, 0, length);
}
outputStream.close();
inputStream.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
//解压------------------------------------------------------------------------------------
/**
* @param zipFileName 压缩文件路径
* @param targetFolder 解压出来的路径
*/
public static void unZip(String zipFileName, String targetFolder) {
try {
deleteDirectory(new File(targetFolder));
File targetFile = new File(targetFolder);
if (!targetFile.exists()) {
targetFile.mkdirs();
}
ZipFile zipFile = new ZipFile(zipFileName);
Enumeration<? extends ZipEntry> entries = zipFile.entries();
while (entries.hasMoreElements()) {
ZipEntry zipEntry = entries.nextElement();
// 在这里可以对每个条目进行操作
unZipChild(zipFile, zipEntry, targetFolder);
}
zipFile.close();
} catch (IOException e) {
e.printStackTrace();
}
}
//压缩------------------------------------------------------------------------------------
/**
* 压缩文件和文件夹
*
* @param srcFileString 要压缩的文件或文件夹
* @param zipFileString 压缩完成的Zip路径
* @throws Exception
*/
public static void ZipFolder(String srcFileString, String zipFileString, String zipName) {
//创建ZIP
ZipOutputStream outZip = null;
try {
//创建文件
File file = new File(srcFileString);
File outPath = new File(zipFileString);
if (!outPath.exists()) {
outPath.mkdirs();
}
outZip = new ZipOutputStream(new FileOutputStream(new File(outPath, zipName)));
//压缩
ZipFiles(file.getParent() + File.separator, file.getName(), outZip);
} catch (Exception e) {
e.printStackTrace();
} finally {
//完成和关闭
if (outZip != null) {
try {
outZip.flush();
outZip.finish();
outZip.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
that's all------------------------------------------------------------------------------------------------------