所有
这是我第一次在这里发帖 - 过去几天我搜索了几个小时。这不是我制作的第一个客户端/服务器应用程序，而且我完全不知道出了什么问题。
我有一台Java服务器（并且它能够正确地读取我的iOS客户端的请求 - 它甚至可以生成响应并且似乎正确发送，但是在iOS客户端上没有可读取的数据）：
public void run() {
BufferedReader in;
try {
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
OutputStream out_stream = this.socket.getOutputStream();
StringBuilder request = new StringBuilder();
String request_buffer;
while ((request_buffer = in.readLine()) != null) {
request.append(request_buffer);
}
out_stream.write(processRequest(request.toString()).getBytes());
out_stream.close();
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
提供的Java函数作为生成它所属的类的实例的结果而被调用，并且它使用ServerSocket的accept（）方法的结果进行初始化。一切似乎在这里工作正常 - 以下Python客户端能够发送请求（甚至读取响应）：
DEFAULT_HOST = ''
DEFAULT_PORT = 2012
RECEIVE_BUFFER_SIZE = 4096
if __name__ == "__main__":
import sys, socket
port = DEFAULT_PORT
host = DEFAULT_HOST
if len(sys.argv) > 2:
host = sys.argv[1]
del sys.argv[1]
if len(sys.argv) == 2:
request = sys.argv[1]
print "Requesting: %s" % request
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, port))
s.send(request)
s.shutdown(socket.SHUT_WR)
response = ""
message = True
while message:
message = s.recv(RECEIVE_BUFFER_SIZE)
response += message
print "Response: %s" % response
在发布iOS客户端之前，我已经使用以下Python服务器对其进行了测试（并且iOS客户端可以按预期读/写..这也适用于Python测试客户端）：
import os, sys
DEFAULT_HOST = ''
DEFAULT_PORT = 4150
# Simple test server
DEFAULT_SIZE = 4096
import socket
class Server:
def __init__(self, host, port, root, protocol, debug=True):
self.debug = debug
self.host = host
self.port = port
self.root = root
self.protocol = protocol
def __call__(self):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((self.host, self.port))
s.listen(5)
while True:
try:
c = s.accept()
print "Connection: %s" % str(c)
request = c[0].recv(DEFAULT_SIZE)
print "Request: %s" % request
try:
response = "test"
if self.debug:
print "Response: %s" % response
except Exception as ex:
print "Error generating response: %s" % ex
if response:
c[0].send(response)
else:
c[0].send("3rr0rZ")
c[0].close()
print
except Exception as ex:
print ex
if __name__ == "__main__":
host = DEFAULT_HOST
port = DEFAULT_PORT
args = sys.argv
# choose a port
if len(args) > 1 and args[1] == "-p":
if len(args) < 3:
raise Exception("Missing Argument for %s" % "-p")
port = int(args[2])
del args[1:3]
else:
port = DEFAULT_PORT
# check if root specified
if len(args) > 1:
root = os.path.realpath(args[1])
del args[1]
else:
root = os.getcwd()
print "Using:"
print "\tHost: %s" % host
print "\tPort: %s" % port
print "\tRoot: %s" % root
print
server = Server(host, port, root)
server()
显然这是一个简化的服务器 - 问题不在于如何生成请求。对于更多背景，请求和响应是JSON字符串，但这并不完全相关。如前所述，Python客户端能够成功地从Java和Python服务器请求和接收响应。 iOS客户端可以成功地向Python和Java服务器发送请求，但它只能从Python服务器读取响应。这是iOS客户端的相关部分：
- (NSData *)sendMessage:(NSData *)request
{
// Create low-level read/write stream objects
CFReadStreamRef readStream = nil;
CFWriteStreamRef writeStream = nil;
// Create high-level stream objects
NSInputStream *inputStream = nil;
NSOutputStream *outputStream = nil;
// Connect the read/write streams to a socket
CFStreamCreatePairWithSocketToHost(nil, (__bridge CFStringRef) self.address, self.port, &readStream, &writeStream);
// Create input/output streams for the raw read/write streams
if (readStream && writeStream) {
CFReadStreamSetProperty(readStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
CFWriteStreamSetProperty(writeStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
inputStream = (__bridge_transfer NSInputStream *)readStream;
[inputStream open];
outputStream = (__bridge_transfer NSOutputStream *)writeStream;
[outputStream open];
}
NSLog(@"Sending message to server: %@", request);
[outputStream write:[request bytes] maxLength:[request length]];
[outputStream close];
int size;
int buffer_size = 1024;
uint8_t buffer[buffer_size];
NSMutableData *response = [NSMutableData dataWithLength:0];
while (![inputStream hasBytesAvailable]);
NSLog(@"About to read");
while ([inputStream streamStatus] == NSStreamStatusOpen)
{
if ([inputStream hasBytesAvailable] && (size = [inputStream read:buffer maxLength:buffer_size]) > 0)
{
NSLog(@"Reading response data");
[response appendData:[NSData dataWithBytes:buffer length:size]];
}
}
NSLog(@"\tResponse:%@", response);
return response;
}
从Java服务器读取时，iOS客户端永远不会越过以下行：
while (![inputStream hasBytesAvailable]);
我已经阅读了我可以找到的各种搜索字词的所有文档，论坛帖子，问题等，但没有任何帮助;我希望这里有人可以解决这个问题！我已经发布了我正在使用的代码的略微简化/扁平版本，但是，再次，这应该足以建立上下文..如果有必要，我会很乐意发布更多代码，并且我感谢任何帮助或洞察力你可以分享。
我故意不使用NSStreamDelegate，我无法想象这是一个问题。如果我是，我想象问题只会变成NSStreamEventHasBytesAvailable永远不会发生。
答案 0 :(得分：2)
试试我的代码，它适用于我。
NSInputStream *inputStream;
NSOutputStream *outputStream;
-(void) init{
NSURL *website = [NSURL URLWithString:@"http://YOUR HOST"];
CFReadStreamRef readStream;
CFWriteStreamRef writeStream;
CFStreamCreatePairWithSocketToHost(NULL,CFBridgingRetain([website host]),9876, &readStream, &writeStream);
inputStream = (__bridge_transfer NSInputStream *)readStream;
outputStream = (__bridge_transfer NSOutputStream *)writeStream;
[inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[outputStream open];
[inputStream open];
CFReadStreamSetProperty(readStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
CFWriteStreamSetProperty(writeStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
}
- (void) sendMessage {
// it is important to add "\n" to the end of the line
NSString *response = @"Say hello to Ukraine\n";
NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSUTF8StringEncoding]];
int sent = [outputStream write:[data bytes] maxLength:[data length]];
NSLog(@"bytes sent: %d",sent);
do{
uint8_t buffer[1024];
int bytes = [inputStream read:buffer maxLength:sizeof(buffer)];
NSString *output = [[NSString alloc] initWithBytes:buffer length:bytes encoding:NSUTF8StringEncoding];
NSLog(@"%@",output);
} while ([inputStream hasBytesAvailable]);
}
public class ServerTest {
public static void main(String[] args) {
Thread thr = new Thread(new SocketThread());
thr.start();
}
}
class SocketThread implements Runnable {
@Override
public void run() {
try {
ServerSocket server = new ServerSocket(9876);
while (true) {
new SocketConnection(server.accept()).start();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
class SocketConnection extends Thread {
InputStream input;
PrintWriter output;
Socket socket;
public SocketConnection(Socket socket) {
super("Thread 1");
this.socket = socket;
try {
input = socket.getInputStream();
output = new PrintWriter(new OutputStreamWriter(
socket.getOutputStream()));
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void run() {
try {
byte array[] = new byte[1024];
while (true) {
do {
int readed = input.read(array);
System.out.println("readed == " + readed + " "
+ new String(array).trim());
String sendString = new String(
"Hello Ukraine!".getBytes(),
Charset.forName("UTF-8"));
output.write(sendString);
output.flush();
} while (input.available() != 0);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
答案 1 :(得分：0)
您的python服务器和Java服务器不等效。在python中，你会这样读：
request = c[0].recv(DEFAULT_SIZE)
在块中读取最多4096个字节。而在Java中你正在使用：
while ((request_buffer = in.readLine()) != null)
in.readLine（）将阻塞，直到它结束行，或者直到它到达文件结尾。可能这会被卡住，直到客户端关闭套接字。您确定客户端正确关闭输出流吗？我不熟悉Objective C，但关闭输出流可能与关闭套接字的写入端不一样。
如果您负责线路的两侧，我会让客户端先写入一个长度标头（两个字节），然后再写入那么多的数据。然后服务器可以读取两个字节，计算剩余数据的长度，并读取那么多。
Length (2-bytes) | Data (length bytes) ---------------------------------------------------------- 0x000C | Hello World!
通过始终发送长度后跟数据，您甚至可以在不关闭套接字的情况下发送多条消息。