解压缩android上的文件似乎非常慢。起初我以为这只是模拟器，但在手机上似乎是一样的。我尝试过不同的压缩级别，并最终降级到存储模式，但仍需要很长时间。
无论如何，一定有理由！还有其他人有这个问题吗？我的解压缩方法如下所示：
public void unzip()
{
try{
FileInputStream fin = new FileInputStream(zipFile);
ZipInputStream zin = new ZipInputStream(fin);
File rootfolder = new File(directory);
rootfolder.mkdirs();
ZipEntry ze = null;
while ((ze = zin.getNextEntry())!=null){
if(ze.isDirectory()){
dirChecker(ze.getName());
}
else{
FileOutputStream fout = new FileOutputStream(directory+ze.getName());
for(int c = zin.read();c!=-1;c=zin.read()){
fout.write(c);
}
//Debug.out("Closing streams");
zin.closeEntry();
fout.close();
}
}
zin.close();
}
catch(Exception e){
//Debug.out("Error trying to unzip file " + zipFile);
}
}
我不知道在Android上解压缩是否很慢，但在循环中复制字节字节肯定会使速度更慢。尝试使用BufferedInputStream和BufferedOutputStream - 它可能有点复杂，但根据我的经验，它最终是值得的。
BufferedInputStream in = new BufferedInputStream(zin);
BufferedOutputStream out = new BufferedOutputStream(fout);
然后你可以用这样的东西写：
byte b[] = new byte[1024];
int n;
while ((n = in.read(b,0,1024)) >= 0) {
out.write(b,0,n);
}
感谢Robert的解决方案。我修改了我的解压缩方法，现在只用了几秒钟而不是2分钟。也许某人对我的解决方案感兴趣。所以你走了：
public void unzip() {
try {
FileInputStream inputStream = new FileInputStream(filePath);
ZipInputStream zipStream = new ZipInputStream(inputStream);
ZipEntry zEntry = null;
while ((zEntry = zipStream.getNextEntry()) != null) {
Log.d("Unzip", "Unzipping " + zEntry.getName() + " at "
+ destination);
if (zEntry.isDirectory()) {
hanldeDirectory(zEntry.getName());
} else {
FileOutputStream fout = new FileOutputStream(
this.destination + "/" + zEntry.getName());
BufferedOutputStream bufout = new BufferedOutputStream(fout);
byte[] buffer = new byte[1024];
int read = 0;
while ((read = zipStream.read(buffer)) != -1) {
bufout.write(buffer, 0, read);
}
zipStream.closeEntry();
bufout.close();
fout.close();
}
}
zipStream.close();
Log.d("Unzip", "Unzipping complete. path : " + destination);
} catch (Exception e) {
Log.d("Unzip", "Unzipping failed");
e.printStackTrace();
}
}
public void hanldeDirectory(String dir) {
File f = new File(this.destination + dir);
if (!f.isDirectory()) {
f.mkdirs();
}
}
使用来自其他来源的上述想法和想法，我创建了这个类
创建这个新类
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import android.util.Log;
public class DecompressFast {
private String _zipFile;
private String _location;
public DecompressFast(String zipFile, String location) {
_zipFile = zipFile;
_location = location;
_dirChecker("");
}
public void unzip() {
try {
FileInputStream fin = new FileInputStream(_zipFile);
ZipInputStream zin = new ZipInputStream(fin);
ZipEntry ze = null;
while ((ze = zin.getNextEntry()) != null) {
Log.v("Decompress", "Unzipping " + ze.getName());
if(ze.isDirectory()) {
_dirChecker(ze.getName());
} else {
FileOutputStream fout = new FileOutputStream(_location + ze.getName());
BufferedOutputStream bufout = new BufferedOutputStream(fout);
byte[] buffer = new byte[1024];
int read = 0;
while ((read = zin.read(buffer)) != -1) {
bufout.write(buffer, 0, read);
}
bufout.close();
zin.closeEntry();
fout.close();
}
}
zin.close();
Log.d("Unzip", "Unzipping complete. path : " +_location );
} catch(Exception e) {
Log.e("Decompress", "unzip", e);
Log.d("Unzip", "Unzipping failed");
}
}
private void _dirChecker(String dir) {
File f = new File(_location + dir);
if(!f.isDirectory()) {
f.mkdirs();
}
}
}
用法
只需将zip文件的文件位置和目标位置传递给此类 例
String zipFile = Environment.getExternalStorageDirectory() + "/the_raven.zip"; //your zip file location
String unzipLocation = Environment.getExternalStorageDirectory() + "/unzippedtestNew/"; // unzip location
DecompressFast df= new DecompressFast(zipFile, unzipLocation);
df.unzip();
不要忘记在清单中添加以下权限（如果版本高于marshmellow，也是运行时权限）
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
希望这可以帮助
帮助我学习如何压缩和解压缩的URL可以找到here。
我将该URL与user3203118的上述答案结合使用以进行解压缩。这是针对遇到此问题并需要帮助解决问题的人员的未来参考资料。
下面是我正在使用的ZipManager代码：
public class ZipManager {
private static final int BUFFER = 80000;
public void zip(String[] _files, String zipFileName) {
try {
BufferedInputStream origin = null;
FileOutputStream dest = new FileOutputStream(zipFileName);
ZipOutputStream out = new ZipOutputStream(new BufferedOutputStream(
dest));
byte data[] = new byte[BUFFER];
for (int i = 0; i < _files.length; i++) {
Log.v("Compress", "Adding: " + _files[i]);
FileInputStream fi = new FileInputStream(_files[i]);
origin = new BufferedInputStream(fi, BUFFER);
ZipEntry entry = new ZipEntry(_files[i].substring(_files[i]
.lastIndexOf("/") + 1));
out.putNextEntry(entry);
int count;
while ((count = origin.read(data, 0, BUFFER)) != -1) {
out.write(data, 0, count);
}
origin.close();
}
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public void unzip(String _zipFile, String _targetLocation) {
// create target location folder if not exist
dirChecker(_targetLocation);
try {
FileInputStream fin = new FileInputStream(_zipFile);
ZipInputStream zin = new ZipInputStream(fin);
ZipEntry ze = null;
while ((ze = zin.getNextEntry()) != null) {
// create dir if required while unzipping
if (ze.isDirectory()) {
dirChecker(ze.getName());
} else {
FileOutputStream fout = new FileOutputStream(
_targetLocation + "/" + ze.getName());
BufferedOutputStream bufout = new BufferedOutputStream(fout);
byte[] buffer = new byte[1024];
int read = 0;
while ((read = zin.read(buffer)) != -1) {
bufout.write(buffer, 0, read);
}
zin.closeEntry();
bufout.close();
fout.close();
}
}
zin.close();
} catch (Exception e) {
System.out.println(e);
}
}
private void dirChecker(String dir) {
File f = new File(dir);
if (!f.isDirectory()) {
f.mkdirs();
}
}
}
只需调用此方法，它将为您提供更好的性能..
public boolean unzip(Context context) {
try {
FileInputStream fin = new FileInputStream(_zipFile);
ZipInputStream zin = new ZipInputStream(fin);
BufferedInputStream in = new BufferedInputStream(zin);
ZipEntry ze = null;
while ((ze = zin.getNextEntry()) != null) {
Log.v("Decompress", "Unzipping " + ze.getName());
if (ze.isDirectory()) {
_dirChecker(ze.getName());
} else {
FileOutputStream fout = new FileOutputStream(_location
+ ze.getName());
BufferedOutputStream out = new BufferedOutputStream(fout);
byte b[] = new byte[1024];
for (int c = in.read(b,0,1024); c != -1; c = in.read()) {
out.write(b,0,c);
}
zin.closeEntry();
fout.close();
}
}
zin.close();
return true;
} catch (Exception e) {
Log.e("Decompress", "unzip", e);
return false;
}
}
private void _dirChecker(String dir) {
File f = new File(_location + dir);
if (!f.isDirectory()) {
f.mkdirs();
}
}
如果使用BufferedOutputStream，请务必刷新它。如果不这样做，小于缓冲区的大小将无法正确解压缩
if (ze.isDirectory()) {
_dirChecker(ze.getName());
} else {
FileOutputStream fout = new FileOutputStream(_location
+ ze.getName());
BufferedOutputStream out = new BufferedOutputStream(fout);
byte buffer[] = new byte[1024];
for (int c = in.read(buffer,0,1024); c != -1; c = in.read()) {
out.write(buffer,0,c);
}
out.flush();//flush it......
zin.closeEntry();
fout.close();
}