无涯教程-Java NIO - SocketChannel Socket通道可以通过调用其静态 open()方法来创建，

Socket通道可以通过调用其静态 open()方法来创建，然后调用 connect()方法进行链接，如果连接失败，则引发NotYetConnectedException异常。可以通过调用其 isConnected 方法来判断是否已连接。

Socket通道可以通过 finishConnect()方法来完成。可以通过调用isConnectionPending方法来确定是否正在进行连接操作。

重要函数

bind(SocketAddress local) - 此方法用于将Socket通道绑定本地地址。
connect(SocketAddress remote) - 此方法用于将Socket连接到远程地址。
finishConnect() - 此方法用于完成Socket通道的连接过程。
getRemoteAddress() - 此方法返回通道Socket连接到的远程位置的地址。
isConnected() - 此方法返回Socket通道的连接状态，即是否已连接。
open()和open(SocketAddress remote) - 使用open方法打开Socket通道。
read(ByteBuffer dst) - 此方法用于通过Socket通道从给指定的缓冲区中读取数据。
isConnectionPending() - 此方法用于判断此通道上是否正在进行连接操作。

SocketChannel示例

以下示例显示了如何从Java NIO SocketChannel发送数据。

C:/Test/temp.txt

Hello World!

客户端代码

SocketChannelClient.java

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardOpenOption;
import java.util.EnumSet;
public class SocketChannelClient {
public static void main(String[] args) throws IOException {
ServerSocketChannel serverSocket = null;
SocketChannel client = null;
serverSocket = ServerSocketChannel.open();
serverSocket.socket().bind(new InetSocketAddress(9000));
client = serverSocket.accept();
System.out.println("Connection Set:  " + client.getRemoteAddress());
Path path = Paths.get("C:/Test/temp1.txt");
FileChannel fileChannel = FileChannel.open(path,
EnumSet.of(StandardOpenOption.CREATE,
StandardOpenOption.TRUNCATE_EXISTING,
StandardOpenOption.WRITE)
);

ByteBuffer buffer = ByteBuffer.allocate(1024);
while(client.read(buffer) > 0) {
buffer.flip();
fileChannel.write(buffer);
buffer.clear();
}
fileChannel.close();
System.out.println("File Received");
client.close();
}
}

在服务器启动之前，运行客户端将不会打印任何内容。

服务器代码

SocketChannelServer.java

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.SocketChannel;
import java.nio.file.Path;
import java.nio.file.Paths;
public class SocketChannelServer {
public static void main(String[] args) throws IOException {
SocketChannel server = SocketChannel.open();
SocketAddress socketAddr = new InetSocketAddress("localhost", 9000);
server.connect(socketAddr);
  </span><span class="typ">Path</span><span class="pln"> path </span><span class="pun">=</span><span class="pln"> </span><span class="typ">Paths</span><span class="pun">.</span><span class="kwd">get</span><span class="pun">(</span><span class="str">"C:/Test/temp.txt"</span><span class="pun">);</span><span class="pln">
  </span><span class="typ">FileChannel</span><span class="pln"> fileChannel </span><span class="pun">=</span><span class="pln"> </span><span class="typ">FileChannel</span><span class="pun">.</span><span class="pln">open</span><span class="pun">(</span><span class="pln">path</span><span class="pun">);</span><span class="pln">
  </span><span class="typ">ByteBuffer</span><span class="pln"> buffer </span><span class="pun">=</span><span class="pln"> </span><span class="typ">ByteBuffer</span><span class="pun">.</span><span class="pln">allocate</span><span class="pun">(</span><span class="lit">1024</span><span class="pun">);</span><span class="pln">
  </span><span class="kwd">while</span><span class="pun">(</span><span class="pln">fileChannel</span><span class="pun">.</span><span class="pln">read</span><span class="pun">(</span><span class="pln">buffer</span><span class="pun">)</span><span class="pln"> </span><span class="pun">&gt;</span><span class="pln"> </span><span class="lit">0</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
     buffer</span><span class="pun">.</span><span class="pln">flip</span><span class="pun">();</span><span class="pln">
     server</span><span class="pun">.</span><span class="pln">write</span><span class="pun">(</span><span class="pln">buffer</span><span class="pun">);</span><span class="pln">
     buffer</span><span class="pun">.</span><span class="pln">clear</span><span class="pun">();</span><span class="pln">
  </span><span class="pun">}</span><span class="pln">
  fileChannel</span><span class="pun">.</span><span class="pln">close</span><span class="pun">();</span><span class="pln">
  </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="str">"File Sent"</span><span class="pun">);</span><span class="pln">
  server</span><span class="pun">.</span><span class="pln">close</span><span class="pun">();</span><span class="pln">

}
}

运行服务器将打印以下内容。

Connection Set:  /127.0.0.1:49558
File Received

无涯教程-Java NIO - SocketChannel

重要函数

SocketChannel示例

客户端代码

服务器代码

参考链接