像舍瓦建议你可以将文件分成大块。我用这个分裂我的4MB的文件
public static void main(String[] args) throws Exception {
String base = "tracks";
String ext = ".dat";
int split = 1024 * 1024;
byte[] buf = new byte[1024];
int chunkNo = 1;
File inFile = new File(base + ext);
FileInputStream fis = new FileInputStream(inFile);
while (true) {
FileOutputStream fos = new FileOutputStream(new File(base + chunkNo + ext));
for (int i = 0; i < split/buf.length; i++) {
int read = fis.read(buf);
fos.write(buf, 0, read);
if (read < buf.length) {
fis.close();
fos.close();
return;
}
}
fos.close();
chunkNo++;
}
}
如果您不需要的文件再次合并到设备上的单个文件，只需使用InputStream的，这将它们合并到一个上飞。
import java.io.IOException;
import java.io.InputStream;
import android.content.res.AssetManager;
public class SplitFileInputStream extends InputStream {
private String baseName;
private String ext;
private AssetManager am;
private int numberOfChunks;
private int currentChunk = 1;
private InputStream currentIs = null;
public SplitFileInputStream(String baseName, String ext, int numberOfChunks, AssetManager am) throws IOException {
this.baseName = baseName;
this.am = am;
this.numberOfChunks = numberOfChunks;
this.ext = ext;
currentIs = am.open(baseName + currentChunk + ext, AssetManager.ACCESS_STREAMING);
}
@Override
public int read() throws IOException {
int read = currentIs.read();
if (read == -1 && currentChunk < numberOfChunks) {
currentIs.close();
currentIs = am.open(baseName + ++currentChunk + ext, AssetManager.ACCESS_STREAMING);
return read();
}
return read;
}
@Override
public int available() throws IOException {
return currentIs.available();
}
@Override
public void close() throws IOException {
currentIs.close();
}
@Override
public void mark(int readlimit) {
throw new UnsupportedOperationException();
}
@Override
public boolean markSupported() {
return false;
}
@Override
public int read(byte[] b, int offset, int length) throws IOException {
int read = currentIs.read(b, offset, length);
if (read < length && currentChunk < numberOfChunks) {
currentIs.close();
currentIs = am.open(baseName + ++currentChunk + ext, AssetManager.ACCESS_STREAMING);
read += read(b, offset + read, length - read);
}
return read;
}
@Override
public int read(byte[] b) throws IOException {
return read(b, 0, b.length);
}
@Override
public synchronized void reset() throws IOException {
if (currentChunk == 1) {
currentIs.reset();
} else {
currentIs.close();
currentIs = am.open(baseName + currentChunk + ext, AssetManager.ACCESS_STREAMING);
currentChunk = 1;
}
}
@Override
public long skip(long n) throws IOException {
long skipped = currentIs.skip(n);
if (skipped < n && currentChunk < numberOfChunks) {
currentIs.close();
currentIs = am.open(baseName + ++currentChunk + ext, AssetManager.ACCESS_STREAMING);
skipped += skip(n - skipped);
}
return skipped;
}
}
用法：
ObjectInputStream ois = new ObjectInputStream(new SplitFileInputStream("mytempfile", ".dat", 4, getAssets()));
感谢您的答案，但您使用哪种工具来削减您的大型分贝到每个较小的块？ – anticafe 2010-11-23 03:19:07
尝试了几个现成的免费软件，然后写了另一个:)在linux和mac上，这是一个20行的C代码。 – 2010-11-23 14:56:11
有一个名为split的命令行工具。 – mclin 2011-01-28 08:22:48