diff options
| -rw-r--r-- | core/java/android/os/ProxyFileDescriptorCallback.java | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/core/java/android/os/ProxyFileDescriptorCallback.java b/core/java/android/os/ProxyFileDescriptorCallback.java index 2e9f8d9a6439..e69fb55abe8a 100644 --- a/core/java/android/os/ProxyFileDescriptorCallback.java +++ b/core/java/android/os/ProxyFileDescriptorCallback.java @@ -21,12 +21,14 @@ import android.system.OsConstants; /** * Callback that handles file system requests from ProxyFileDescriptor. + * + * @see android.os.storage.StorageManager#openProxyFileDescriptor(int, ProxyFileDescriptorCallback) */ public abstract class ProxyFileDescriptorCallback { /** * Returns size of bytes provided by the file descriptor. - * @return Size of bytes - * @throws ErrnoException + * @return Size of bytes. + * @throws ErrnoException ErrnoException containing E constants in OsConstants. */ public long onGetSize() throws ErrnoException { throw new ErrnoException("onGetSize", OsConstants.EBADF); @@ -35,11 +37,13 @@ public abstract class ProxyFileDescriptorCallback { /** * Provides bytes read from file descriptor. * It needs to return exact requested size of bytes unless it reaches file end. - * @param offset Where to read bytes from. + * @param offset Offset in bytes from the file head specifying where to read bytes. If a seek + * operation is conducted on the file descriptor, then a read operation is requested, the + * offset refrects the proper position of requested bytes. * @param size Size for read bytes. * @param data Byte array to store read bytes. * @return Size of bytes returned by the function. - * @throws ErrnoException + * @throws ErrnoException ErrnoException containing E constants in OsConstants. */ public int onRead(long offset, int size, byte[] data) throws ErrnoException { throw new ErrnoException("onRead", OsConstants.EBADF); @@ -47,19 +51,23 @@ public abstract class ProxyFileDescriptorCallback { /** * Handles bytes written to file descriptor. - * @param offset Where to write bytes to. + * @param offset Offset in bytes from the file head specifying where to write bytes. If a seek + * operation is conducted on the file descriptor, then a write operation is requested, the + * offset refrects the proper position of requested bytes. * @param size Size for write bytes. * @param data Byte array to be written to somewhere. * @return Size of bytes processed by the function. - * @throws ErrnoException + * @throws ErrnoException ErrnoException containing E constants in OsConstants. */ public int onWrite(long offset, int size, byte[] data) throws ErrnoException { throw new ErrnoException("onWrite", OsConstants.EBADF); } /** - * Processes fsync request. - * @throws ErrnoException + * Ensures all the written data are stored in permanent storage device. + * For example, if it has data stored in on memory cache, it needs to flush data to storage + * device. + * @throws ErrnoException ErrnoException containing E constants in OsConstants. */ public void onFsync() throws ErrnoException { throw new ErrnoException("onFsync", OsConstants.EINVAL); |