有什么理由让我得到这样的回答吗；“空白”；当从C客户机向Java服务器读取套接字时？
我正在尝试使用Java服务器和C客户机实现TCP协议。当从客户端读取第一个输入时，代码正常工作。但是，在客户机第二次输入时，服务器读取“ 嗨“或” command1“即使在我尝试使用line=line.replaceAll（“\s”，”）删除空白之后。这些不是空白吗？是否有垃圾从C读入Java？现在，在我发送第二个命令后，程序被阻止，因为服务器无法识别带有这些空格的命令，并且不会将任何内容发送回客户端。非常感谢您的帮助或建议，谢谢您抽出时间 下面是我的Java服务器代码：有什么理由让我得到这样的回答吗；“空白”；当从C客户机向Java服务器读取套接字时？,java,c,sockets,tcp,bufferedreader,Java,C,Sockets,Tcp,Bufferedreader,我正在尝试使用Java服务器和C客户机实现TCP协议。当从客户端读取第一个输入时，代码正常工作。但是，在客户机第二次输入时，服务器读取“ 嗨“或” command1“即使在我尝试使用line=line.replaceAll（“\s”，”）删除空白之后。这些不是空白吗？是否有垃圾从C读入Java？现在，在我发送第二个命令后，程序被阻止，因为服务器无法识别带有这些空格的命令，并且不会将任何内容发送回客户端。非常感谢您的帮助或建议，谢谢您抽出时间 下面是我的Java服务器代码： // A Java p
// A Java program for a Server
import java.net.*;
import java.io.*;
public class HXServerJava
{
//initialize socket and input stream
private Socket socket = null;
private ServerSocket server = null;
private DataInputStream in = null;
// constructor with port
public HXServerJava(int port)
{
// starts server and waits for a connection
try
{
server = new ServerSocket(port);
System.out.println("Server started");
System.out.println("Waiting for a client ...");
socket = server.accept();
System.out.println("Client accepted");
// takes input from the client socket
BufferedReader in= new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter out=new PrintWriter(socket.getOutputStream(),true);
String line = "";
// reads message from client until "over" is sent
while (!line.equals("over"))
{
try
{
line = in.readLine();
System.out.println("line before is: " + line);
line = line.replaceAll("\\s",""); //trying to get rid of whitespace
System.out.println("line after is: " + line);
if ((line != null && line.equals("hi")==true)) {
out.print("Welcome by server\n");
out.flush();
//out.close();
}
if ((line != null && line.equals("command1")==true)) {
out.print("first command executed\n");
out.flush();
//out.close();
}
}
catch(IOException i)
{
System.out.println(i);
}
}
System.out.println("Closing connection");
out.print("exit\n");
out.flush();
// close connection
socket.close();
in.close();
out.close();
}
catch(IOException i)
{
System.out.println(i);
}
}
public static void main(String args[])
{
HXServerJava server = new HXServerJava(5000);
}
}
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#define MAX 80
#define PORT 5000
#define SA struct sockaddr
void func(int sockfd)
{
char buff[MAX];
int n,m;
char *str;
int exitFlag = 0;
str = malloc(sizeof (char) * MAX);
while (exitFlag != 1){
bzero(buff, sizeof(buff));
printf("Enter the string : ");
n = 0;
while ((buff[n++] = getchar()) != '\n')
;
//strcpy (str, buff);
//strcat(str, "\n");
printf("String is: %s\n",buff);
m = write(sockfd, buff, sizeof(buff));
if (m < 0){
perror ("ERROR writing to socket\n");
}
bzero(buff, sizeof(buff));
m = read(sockfd, buff, sizeof(buff));
if (n < 0) {
perror("ERROR reading from socket\n");
}
printf("From Server : %s\n", buff);
if ((strncmp(buff, "exit", 4)) == 0) {
exitFlag = 1;
printf("Client Exit...\n");
break;
}
}
}
int main()
{
int sockfd, connfd;
struct sockaddr_in servaddr, cli;
// socket create and varification
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd == -1) {
printf("socket creation failed...\n");
exit(0);
}
else
printf("Socket successfully created..\n");
bzero(&servaddr, sizeof(servaddr));
// assign IP, PORT
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
servaddr.sin_port = htons(PORT);
// connect the client socket to server socket
if (connect(sockfd, (SA*)&servaddr, sizeof(servaddr)) != 0) {
printf("connection with the server failed...\n");
exit(0);
}
else
printf("connected to the server..\n");
// function for chat
func(sockfd);
// close the socket
close(sockfd);
}
// A Java program for a Server
import java.net.*;
import java.io.*;
public class HXServerJava
{
//initialize socket and input stream
private Socket socket = null;
private ServerSocket server = null;
private DataInputStream in = null;
// constructor with port
public HXServerJava(int port)
{
// starts server and waits for a connection
try
{
server = new ServerSocket(port);
System.out.println("Server started");
System.out.println("Waiting for a client ...");
socket = server.accept();
System.out.println("Client accepted");
// takes input from the client socket
BufferedReader in= new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter out=new PrintWriter(socket.getOutputStream(),true);
String line = "";
// reads message from client until "over" is sent
while (!line.equals("over"))
{
try
{
line = in.readLine();
System.out.println("line before is: " + line);
line = line.replaceAll("\\s",""); //trying to get rid of whitespace
System.out.println("line after is: " + line);
if ((line != null && line.equals("hi")==true)) {
out.print("Welcome by server\n");
out.flush();
//out.close();
}
if ((line != null && line.equals("command1")==true)) {
out.print("first command executed\n");
out.flush();
//out.close();
}
}
catch(IOException i)
{
System.out.println(i);
}
}
System.out.println("Closing connection");
out.print("exit\n");
out.flush();
// close connection
socket.close();
in.close();
out.close();
}
catch(IOException i)
{
System.out.println(i);
}
}
public static void main(String args[])
{
HXServerJava server = new HXServerJava(5000);
}
}
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#define MAX 80
#define PORT 5000
#define SA struct sockaddr
void func(int sockfd)
{
char buff[MAX];
int n,m;
char *str;
int exitFlag = 0;
str = malloc(sizeof (char) * MAX);
while (exitFlag != 1){
bzero(buff, sizeof(buff));
printf("Enter the string : ");
n = 0;
while ((buff[n++] = getchar()) != '\n')
;
//strcpy (str, buff);
//strcat(str, "\n");
printf("String is: %s\n",buff);
m = write(sockfd, buff, sizeof(buff));
if (m < 0){
perror ("ERROR writing to socket\n");
}
bzero(buff, sizeof(buff));
m = read(sockfd, buff, sizeof(buff));
if (n < 0) {
perror("ERROR reading from socket\n");
}
printf("From Server : %s\n", buff);
if ((strncmp(buff, "exit", 4)) == 0) {
exitFlag = 1;
printf("Client Exit...\n");
break;
}
}
}
int main()
{
int sockfd, connfd;
struct sockaddr_in servaddr, cli;
// socket create and varification
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd == -1) {
printf("socket creation failed...\n");
exit(0);
}
else
printf("Socket successfully created..\n");
bzero(&servaddr, sizeof(servaddr));
// assign IP, PORT
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
servaddr.sin_port = htons(PORT);
// connect the client socket to server socket
if (connect(sockfd, (SA*)&servaddr, sizeof(servaddr)) != 0) {
printf("connection with the server failed...\n");
exit(0);
}
else
printf("connected to the server..\n");
// function for chat
func(sockfd);
// close the socket
close(sockfd);
}
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#定义最大值80
#定义端口5000
#定义SA结构sockaddr
无效函数（int-sockfd）
{
字符buff[MAX]；
int n，m；
char*str；
int-exitFlag=0；
str=malloc（sizeof（char）*MAX）；
while（exitFlag！=1）{
bzero（buff，sizeof（buff））；
printf（“输入字符串：”）；
n=0；
而（（buff[n++]=getchar（））！='\n'）
;
//strcpy（str，buff）；
//strcat（str，“\n”）；
printf（“字符串是：%s\n”，buff）；
m=写入（sockfd，buff，sizeof（buff））；
if（m<0）{
perror（“写入套接字时出错\n”）；
}
bzero（buff，sizeof（buff））；
m=读取（sockfd，buff，sizeof（buff））；
if（n<0）{
perror（“从套接字读取错误\n”）；
}
printf（“来自服务器：%s\n”，buff）；
如果（（strncmp（buff，“exit”，4））==0{
exitFlag=1；
printf（“客户端退出…\n”）；
打破
}
}
}
int main（）
{
int sockfd，connfd；
servaddr中的struct sockaddru，cli；
//套接字创建和变体
sockfd=套接字（AF_INET，SOCK_STREAM，0）；
如果（sockfd==-1）{
printf（“套接字创建失败…\n”）；
出口（0）；
}
其他的
printf（“套接字已成功创建..\n”）；
bzero（&servaddr，sizeof（servaddr））；
//分配IP、端口
servaddr.sin_family=AF_INET；
servaddr.sin_addr.s_addr=inet_addr（“127.0.0.1”）；
servaddr.sinu端口=htons（端口）；
//将客户端套接字连接到服务器套接字
如果（connect（sockfd，（SA*）&servaddr，sizeof（servaddr））！=0{
printf（“与服务器的连接失败…\n”）；
出口（0）；
}
其他的
printf（“连接到服务器..\n”）；
//聊天功能
func（sockfd）；
//合上插座
关闭（sockfd）；
}
sizeof（buff）nprintf（“套接字创建失败…\n”）错误消息应输出到stderr
，而不是stdout
。当错误指示来自C库函数时，还应向stderr
输出系统认为错误发生的文本原因。建议使用peror（）
关于退出（0）main（）exit（exit\u失败）@CarlosHeuberger请将您的评论作为答案，以便OP可以标记它。