我创建了一个简单的客户端/服务器程序,其中客户端从命令行参数获取文件。然后,客户端将文件发送到服务器,在服务器中使用 GZIP 对其进行压缩并发回客户端。
服务器程序第一次运行时很好,并且没有产生任何错误,但在运行客户端后我收到错误。
我收到一条错误消息,表示连接已重置,并且我尝试了许多不同的端口,所以我想知道我的代码或关闭流的时间是否有问题?
任何帮助将不胜感激!
编辑 - 对两个程序进行了更改。
客户:
import java.io.*;
import java.net.*;
//JZip Client
public class NetZip {
//Declaring private variables.
private Socket socket = null;
private static String fileName = null;
private File file = null;
private File newFile = null;
private DataInputStream fileIn = null;
private DataInputStream dataIn = null;
private DataOutputStream dataOut = null;
private DataOutputStream fileOut = null;
public static void main(String[] args) throws IOException {
try {
fileName = args[0];
}
catch (ArrayIndexOutOfBoundsException error) {
System.out.println("Please Enter a Filename!");
}
NetZip x = new NetZip();
x.toServer();
x.fromServer();
}
public void toServer() throws IOException{
while (true){
//Creating socket
socket = new Socket("localhost", 4567);
file = new File(fileName);
//Creating stream to read from file.
fileIn = new DataInputStream(
new BufferedInputStream(
new FileInputStream(
file)));
//Creating stream to write to socket.
dataOut = new DataOutputStream(
new BufferedOutputStream(
socket.getOutputStream()));
byte[] buffer = new byte[1024];
int len;
//While there is data to be read, write to socket.
while((len = fileIn.read(buffer)) != -1){
try{
System.out.println("Attempting to Write " + file
+ "to server.");
dataOut.write(buffer, 0, len);
}
catch(IOException e){
System.out.println("Cannot Write File!");
}
}
fileIn.close();
dataOut.flush();
dataOut.close();
}
}
//Read data from the serversocket, and write to new .gz file.
public void fromServer() throws IOException{
dataIn = new DataInputStream(
new BufferedInputStream(
socket.getInputStream()));
fileOut = new DataOutputStream(
new BufferedOutputStream(
new FileOutputStream(
newFile)));
byte[] buffer = new byte[1024];
int len;
while((len = dataIn.read(buffer)) != -1){
try {
System.out.println("Attempting to retrieve file..");
fileOut.write(buffer, 0, len);
newFile = new File(file +".gz");
}
catch (IOException e ){
System.out.println("Cannot Recieve File");
}
}
dataIn.close();
fileOut.flush();
fileOut.close();
socket.close();
}
}
服务器:
import java.io.*;
import java.net.*;
import java.util.zip.GZIPOutputStream;
//JZip Server
public class ZipServer {
private ServerSocket serverSock = null;
private Socket socket = null;
private DataOutputStream zipOut = null;
private DataInputStream dataIn = null;
public void zipOut() throws IOException {
//Creating server socket, and accepting from other sockets.
try{
serverSock = new ServerSocket(4567);
socket = serverSock.accept();
}
catch(IOException error){
System.out.println("Error! Cannot create socket on port");
}
//Reading Data from socket
dataIn = new DataInputStream(
new BufferedInputStream(
socket.getInputStream()));
//Creating output stream.
zipOut= new DataOutputStream(
new BufferedOutputStream(
new GZIPOutputStream(
socket.getOutputStream())));
byte[] buffer = new byte[1024];
int len;
//While there is data to be read, write to socket.
while((len = dataIn.read(buffer)) != -1){
System.out.println("Attempting to Compress " + dataIn
+ "and send to client");
zipOut.write(buffer, 0, len);
}
dataIn.close();
zipOut.flush();
zipOut.close();
serverSock.close();
socket.close();
}
public static void main(String[] args) throws IOException{
ZipServer run = new ZipServer();
run.zipOut();
}
}
错误消息:
Exception in thread "main" java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:196)
at java.net.SocketInputStream.read(SocketInputStream.java:122)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:235)
at java.io.BufferedInputStream.read1(BufferedInputStream.java:275)
at java.io.BufferedInputStream.read(BufferedInputStream.java:334)
at java.io.DataInputStream.read(DataInputStream.java:100)
at ZipServer.<init>(ZipServer.java:38)
at ZipServer.main(ZipServer.java:49)
最佳答案
首先,发生错误是因为客户端在发送任何数据之前失败并结束,因此
连接在服务器想要读取时关闭。
发生错误的原因是您将 File 对象分配给未使用的局部变量(您的编译器没有警告吗?)
public File file = null;
public File newFile = null;
public static void main(String[] args) throws IOException {
try {
String fileName = args[0];
File file = new File(fileName);
File newFile = new File(file +".gz");
}
catch (ArrayIndexOutOfBoundsException error) {
System.out.println("Please Enter a Filename!");
}
但是在您的 toServer 方法中,您使用类变量 file 作为 FileInputStream 的参数,并且该变量为 null,这会导致错误并结束程序。
其次,如果完成了对输出流的写入,则应该调用
socket.shtdownOutput();
否则,服务器会尝试读取,直到发生超时。
关于java - 线程中的异常 "main"java.net.SocketException : Connection reset -,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27282997/