问题：
如何从字符中清除套接字流，以便将其用于字节（字节文件传输）？
戚奇略
我正在尝试制作一些包含文件传输的程序。当然，我必须使用字符流进行一些客户机-服务器通信，我还需要使用字节流来传输文件。当我从BufferedReader中使用println方法form PrintWriter和readLine时会出现问题，因为readLine读取行，但在流中留下“\n”，这会在我尝试使用字节流传输文件后导致问题（我不能100%确定这就是问题）。所以我需要摆脱这个角色，我尝试使用Reader类中的read方法，但没有成功。代码在不使用字符拖缆的情况下可以完美工作。请注意readLine的调用对sizeOfFile的影响。
服务器
import java.net.ServerSocket;
import java.net.Socket;
public class Server {
private static int SERVER_PORT = 9999;
public static void main(String[] args) {
try {
ServerSocket ss = new ServerSocket(SERVER_PORT);
System.out.println("Server je pokrenut");
while (true) {
Socket sock = ss.accept();
new MultithreadServer(sock);
}
}
catch (Exception e) {
e.printStackTrace();
}
}
}
服务器Thread
import java.io.*;
import java.net.Socket;
import java.util.*;
public class MultithreadServer extends Thread {
private Socket sock;
BufferedReader inChar;
PrintWriter outChar;
BufferedInputStream in;
BufferedOutputStream out;
DataOutputStream outByte;
public MultithreadServer(Socket sock) throws Exception {
this.sock = sock;
inChar = new BufferedReader(
new InputStreamReader(sock.getInputStream()));
outChar = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
sock.getOutputStream())), true);
in = new BufferedInputStream(sock.getInputStream());
out = new BufferedOutputStream(sock.getOutputStream());
outByte = new DataOutputStream(sock.getOutputStream());
start();
}
public void run() {
try {
String request = inChar.readLine();
System.out.println("Fajl: " + request);
File file = new File(request);
BufferedInputStream in = new BufferedInputStream(
new FileInputStream(file));
long sizeOfFile = (long) file.length();
outChar.println("SOME_MESSAGE"); //PROBLEM
byte[] buffer = new byte[4096];
int len = 0;
outByte.writeLong(sizeOfFile);
long totalyTransfered = 0;
while ((len = in.read(buffer, 0, buffer.length)) !=-1) {
out.write(buffer, 0, len);
totalyTransfered += len;
}
System.out.println("Total:" + totalyTransfered);
out.flush();
}
catch (Exception e) {
e.printStackTrace();
}
}
}
客户
import java.util.*;
import java.net.*;
import java.io.*;
public class ClientServer {
static int SERVER_PORT = 9999;
public static void main(String[] args) throws Exception {
InetAddress address = InetAddress.getByName("127.0.0.1");
Socket sock = new Socket(address, SERVER_PORT);
PrintWriter out = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(sock.getOutputStream())), true);
BufferedReader inChar = new BufferedReader(new InputStreamReader(sock.getInputStream()));
Reader readChar = new InputStreamReader(sock.getInputStream());
System.out.println("File:"); // choosing file from server
Scanner consoleInput = new Scanner(System.in);
String file = consoleInput.next();
out.println(file);
DataInputStream in = new DataInputStream(sock.getInputStream());
System.out.println("Type name of file:"); //choosing name for file on client
String newFile = consoleInput.next();
OutputStream outByte = new FileOutputStream(newFile);
byte[] buffer = new byte[4096];
System.out.println("aa"+inChar.readLine()+"aa"); //PROBLEM
System.out.println("SOME_TEXT"+readChar.read()+"SOME_TEXT"); //TRYING TO FIX THE PROBLEM
// in.read(); in.read(); // DIFFERENT TRY
long sizeOfFile= in.readLong(); // BUT IT STILL HAS INFLUENCE OF sizeOfFile
System.out.println("Size of file:" + sizeOfFile);
long totalyTransfered= 0;
int len = 0;
while ((len = in.read(buffer,0,buffer.length)) != -1) {
outByte.write(buffer, 0, len);
System.out.println("In one pass:" + len);
sizeOfFile-=len;
totalyTransfered+=len;
System.out.println("Total:" + totalyTransfered);
if (sizeOfFile<=0)break;
}
System.out.println("Available: "+in.available());
outByte.flush();
outByte.close();
}
}
共有1个答案
林弘文
我修改了你的代码并成功传输了文件，很抱歉我没有时间解决你代码中的问题，我认为你的代码不简单：）。
但是请在下面找到你修改过的代码，它非常简单，我从这里引用了这段代码
class Server:
No changes
类ClientServer：
public class ClientServer {
static int SERVER_PORT = 9999;
private static final String fileOutput = "C:\\testout.pdf";
public static void main(String[] args) throws Exception {
InetAddress address = InetAddress.getByName("127.0.0.1");
Socket sock = new Socket(address, SERVER_PORT);
InputStream is = sock.getInputStream();
PrintWriter out = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(sock.getOutputStream())), true);
BufferedReader inChar = new BufferedReader(new InputStreamReader(sock.getInputStream()));
Reader readChar = new InputStreamReader(sock.getInputStream());
System.out.println("File:"); // choosing file from server
Scanner consoleInput = new Scanner(System.in);
String file = consoleInput.next();
out.println(file);
DataInputStream in = new DataInputStream(sock.getInputStream());
System.out.println("Type name of file:"); //choosing name for file on client
//String newFile = consoleInput.next();
//
// OutputStream outByte = new FileOutputStream(newFile);
// byte[] buffer = new byte[4096];
//
//
// System.out.println("aa"+inChar.readLine()+"aa"); //PROBLEM
// System.out.println("SOME_TEXT"+readChar.read()+"SOME_TEXT"); //TRYING TO FIX THE PROBLEM
// // in.read(); in.read(); // DIFFERENT TRY
// long sizeOfFile= in.readLong(); // BUT IT STILL HAS INFLUENCE OF sizeOfFile
// System.out.println("Size of file:" + sizeOfFile);
//
// long totalyTransfered= 0;
// int len = 0;
// while ((len = in.read(buffer,0,buffer.length)) != -1) {
// outByte.write(buffer, 0, len);
// System.out.println("In one pass:" + len);
// sizeOfFile-=len;
// totalyTransfered+=len;
// System.out.println("Total:" + totalyTransfered);
// if (sizeOfFile<=0)break;
// }
// System.out.println("Available: "+in.available());
// outByte.flush();
// outByte.close();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
FileOutputStream fos = null;
BufferedOutputStream bos = null;
int bytesRead;
try {
byte[] aByte = new byte[1];
fos = new FileOutputStream(fileOutput);
bos = new BufferedOutputStream(fos);
bytesRead = is.read(aByte, 0, aByte.length);
do {
baos.write(aByte);
bytesRead = is.read(aByte);
} while (bytesRead != -1);
bos.write(baos.toByteArray());
bos.flush();
bos.close();
sock.close();
} catch (IOException ex) {
// Do exception handling
}
}
}
类MutithReadServer：
public class MultithreadServer extends Thread {
private Socket sock;
BufferedReader inChar;
PrintWriter outChar;
BufferedInputStream in;
BufferedOutputStream out;
DataOutputStream outByte;
public MultithreadServer(Socket sock) throws Exception {
this.sock = sock;
inChar = new BufferedReader(new InputStreamReader(sock.getInputStream()));
outChar = new PrintWriter(new BufferedWriter(new OutputStreamWriter(sock.getOutputStream())), true);
in = new BufferedInputStream(sock.getInputStream());
out = new BufferedOutputStream(sock.getOutputStream());
outByte = new DataOutputStream(sock.getOutputStream());
start();
}
public void run() {
try {
String request = inChar.readLine();
System.out.println("Fajl: " + request);
File file = new File(request);
BufferedInputStream in = new BufferedInputStream(
new FileInputStream(file));
byte[] buffer = new byte[(int) file.length()];
FileInputStream fis = null;
try {
fis = new FileInputStream(file);
} catch (FileNotFoundException ex) {
// Do exception handling
}
BufferedInputStream bis = new BufferedInputStream(fis);
//long sizeOfFile = (long) file.length();
//outChar.println("SOME_MESSAGE"); //PROBLEM
//byte[] buffer = new byte[4096];
try {
bis.read(buffer, 0, buffer.length);
out.write(buffer, 0, buffer.length);
out.flush();
out.close();
sock.close();
// File sent, exit the main method
return;
} catch (IOException ex) {
// Do exception handling
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
注意：没有几行未使用的代码，请删除。希望它能在周日有所帮助：）！！！
类似资料：
-
如何将字符串（字节字符串）转换为字节（字节字符串），而不必手动复制和粘贴字符串并在其前面放置b？
-
问题内容： 请解释什么是字节流和字符流。这些到底是什么意思？Microsoft Word文档是面向字节还是面向字符？ 谢谢 问题答案： 流是顺序访问文件的一种方式。字节流逐字节访问文件。字节流适用于任何类型的文件，但不适用于文本文件。例如，如果文件使用unicode编码，并且一个字符用两个字节表示，则字节流将分别处理这些字节，您需要自己进行转换。 字符流将逐字符读取文件。必须为字符流提供文件的编码
-
我在将JSON对象转换为字节时遇到了一个问题。我需要这样的东西： 我将感激任何帮助。提前道谢。
-
我正在建立一个自定义的文件创建与Android应用程序。我试图将Bytebuffer的内容（它是我创建的自定义类中的字符串成员）写入字节类型的文件。但是，每当我这样做时，我得到的是字符串格式的文件内容。我尝试了几种替代方法，例如使用get方法、BufferedOutputStream类、ByteArrayOutputStream类、DataOutputStream类、Filechannel类等。以
-
我有一个类，它接收用户发送的消息并在终端上打印出来，但现在我正在尝试编写一个类，从用户那里读取数据，将来自用户的字符串数据转换成字节数组，并将字节数组写入套接字。 我试图使用BufferedReader从用户读取数据，并使用OutputStream将字节数组写入套接字，但由于某些原因，我正在写入套接字的消息没有传递到服务器。 是一个与我发送到的服务器和端口号相同的套接字！ 当我运行这个时没有错误，
-
Spring似乎无法将响应直接流式传输到文件，而不将其全部缓冲在内存中。使用较新的Spring 5实现这一点的正确方法是什么？ 我看到人们在中找到了一些解决此问题的方法，但我更感兴趣的是使用以正确的方式解决此问题。 有许多使用下载二进制数据的示例，但几乎所有示例都将加载到内存中。