Java APIs

Hi all,
i construct a program that send in java integer numbers (that transfer to byte array) over a datagram socket.
at the receive side i did in c/c++ (it has to be in c/c++).
when i send numbers between 1 -127 everything pass fine but when i send numbers large than 127 (for example 128 129 etc...)
i got negative numbers at the c/c++ side.

i also make some test at the java side i convert it to byte array and than convert it back to integer and the wright number has got.

this is my code:

client at java side:

private void sendProcedure() throws Exception {
		// TODO Auto-generated method stub
		DatagramSocket serverSocket = new DatagramSocket();
		byte[] receiveData = new byte[1024];
		byte[] sendData = new byte[1024];
		String IpDest ="127.0.0.1";
		int getVal= convertStringToInt(jTextField.getText());

		InetAddress IPAddress = InetAddress.getByName(IpDest);// receivePacket.getAddress();
		int port = 12345;//receivePacket.getPort();
		sendData =intToByteArray(getVal);// capitalizedSentence.getBytes();
		sendData= reverseArray(sendData);
		DatagramPacket sendPacket =	new DatagramPacket(sendData, sendData.length, IPAddress, port);
		serverSocket.send(sendPacket);
         
	}

public static byte[] intToByteArray(int intValue) {
				
		ByteBuffer b = ByteBuffer.allocate(4);
		//b.order(ByteOrder..BIG_ENDIAN); // optional, the initial order of a byte buffer is always BIG_ENDIAN.
		b.putInt(intValue);

		byte[] result = b.array();
		
		//for test
		int testnum= bytesToInt(result);
		System.out.println("reverse value is="+testnum);

	 return result;
		
	}
	
	private static int bytesToInt(byte[] intBytes){
		ByteBuffer bb = ByteBuffer.wrap(intBytes);
		return bb.getInt();
	}
	
	public byte[] reverseArray(byte[] arr)
	{
		int left = 0;
		int right = arr.length - 1;
		while (left < right) {
			byte temp = arr[left];
			arr[left] = arr[right];
			arr[right] = temp;
			left++;
			right--;
		}
		return arr;
	}

Server Side at c/c++:

#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>


#define BUFLEN 512
#define NPACK 100
#define PORT 12345
typedef char byte;
   void diep(char *s)
 {
   perror(s);
   exit(1);
 }

int convertToNUms()
{

	return 1;
}

uint GetInt32( byte *pBytes )
{
	uint i0= (uint)(*(pBytes + 3)) << 24;
	uint i1= (uint)(*(pBytes + 2)) << 16;
	uint i2= (uint)(*(pBytes + 1)) << 8;
	uint i3= (uint)(*(pBytes + 0));
	uint res= i0|i1|i2|i3;
	printf("i0=%d\n",i0);
	printf("i1=%d\n",i1);
	printf("i2=%d\n",i2);
	printf("i3=%d\n",i3);
	printf("Res=%d\n",res);

	return (uint)(*(pBytes + 3) << 24 | *(pBytes + 2) << 16 | *(pBytes + 1) << 8 | *pBytes);
}

int main(void)
 {
	struct sockaddr_in si_me, si_other;
	int s, i, slen=sizeof(si_other);
	char buf[5];
	int var1;


	if ((s=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
		diep("socket");
	memset((char *) &si_me, 0, sizeof(si_me));
	si_me.sin_family = AF_INET;
	si_me.sin_port = htons(PORT);
	si_me.sin_addr.s_addr = htonl(INADDR_ANY);
	if (bind(s, &si_me, sizeof(si_me))==-1)
		diep("bind");
	for (i=0; i<NPACK; i++) {
		if (recvfrom(s, buf, BUFLEN, 0, &si_other, &slen)==-1)
			diep("recvfrom()");

		var1 = GetInt32(buf);//here I have to do casting.
		printf("Received packet from %s:%d\nData: %d\n\n",
				inet_ntoa(si_other.sin_addr), ntohs(si_other.sin_port), var1);
	}
	close(s);
	return 0;
}

THanks for the attentaion