java readunsignedint,Java读取unsigned int，存储并将其写回

I need to read an unsigned int from a quicktime file, and write it back to another quicktime file.

Currently I read the unsigned int into a Long but while writing it back I never managed to write the exact number back in 4 bytes as unsigned int. The long has the correct value that I need to write back.

(eg 3289763894 or 370500)

I am unable to even read the write a number smaller then Integer.MAX_VALUE (eg 2997).

I am using the following methods to write the value back

public void writeUInt32(long uint32,DataOutputStream stream) throws IOException {

writeUInt16((int) (uint32 & 0xffff0000) >> 16,stream);

writeUInt16((int) uint32 & 0x0000ffff,stream);

}

public void writeUInt16(int uint16,DataOutputStream stream) throws IOException {

writeUInt8(uint16 >> 8, stream);

writeUInt8(uint16, stream);

}

public void writeUInt8(int uint8,DataOutputStream stream) throws IOException {

stream.write(uint8 & 0xFF);

}

Any help would be appreciated.

解决方案

Just write your long casted to int. I checked:

PipedOutputStream pipeOut = new PipedOutputStream ();

PipedInputStream pipeIn = new PipedInputStream (pipeOut);

DataOutputStream os = new DataOutputStream (pipeOut);

long uInt = 0xff1ffffdL;

System.out.println ("" + uInt + " vs " + ((int) uInt));

os.writeInt ((int) uInt);

for (int i = 0; i < 4; i++) System.out.println (pipeIn.read ());

uInt = 0x000ffffdL;

System.out.println ("" + uInt + " vs " + ((int) uInt));

os.writeInt ((int) uInt);

for (int i = 0; i < 4; i++) System.out.println (pipeIn.read ());

Output is4280287229 vs -14680067

255

31

255

253

1048573 vs 1048573

0

15

255

253as expected