RMI（java.net.ConnectException：连接被拒绝：连接）

Question

我试图运行名为SampleServer的服务器。我使用Windows，这是我做过什么：

在cmd中

：

javaw rmiregistry 1099 
cd C:\Users\Home\workspace\RMI\src 
java -Djava.security.policy=policy SampleServer 1099 

我得到以下错误：

binding //localhost:1099/Sample 
New instance of Sample created 
Sample server failed:Connection refused to host: localhost; nested exception is: 

     java.net.ConnectException: Connection refused: connect 

我使用不同的端口号，例如4719尝试为rmiregistry，但我收到相同的错误。我确定我的防火墙已被禁用，但问题仍然存在。我确定该端口尚未被使用。我真的希望有人能帮助我。

图片我的桌面与项目的文件夹，Eclipse窗口和CMD打开的： http://s22.postimg.org/uq00qzslr/picyture.png

代码：

SampleServer：

import java.rmi.Naming; 
import java.rmi.RemoteException; 
import java.rmi.RMISecurityManager; 
import java.rmi.server.UnicastRemoteObject; 

public class SampleServer { 
    public static void main(String args[]) { 
     if (args.length != 1) { 
      System.err.println("usage: java SampleServer rmi_port"); 
      System.exit(1); 
     } 
     // Create and install a security manager 
     if (System.getSecurityManager() == null) 
      System.setSecurityManager(new RMISecurityManager()); 
     try { 
      // first command-line argument is the port of the rmiregistry 
      int port = Integer.parseInt(args[0]); 
      String url = "//localhost:" + port + "/Sample"; 
      System.out.println("binding " + url); 
      Naming.rebind(url, new Sample()); 
      // Naming.rebind("Sample", new Sample()); 
      System.out.println("server " + url + " is running..."); 
     } 
     catch (Exception e) { 
      System.out.println("Sample server failed:" + e.getMessage()); 
     } 
    } 
} 

SampleClient：

import java.rmi.Naming; 
import java.rmi.RemoteException; 

public class SampleClient { 
    public static void main(String args[]) { 
     try { 
      if (args.length < 3) { 
       System.err.println("usage: java SampleClient host port string... \n"); 
       System.exit(1); 
      } 

      int port = Integer.parseInt(args[1]); 
      String url = "//" + args[0] + ":" + port + "/Sample"; 
      System.out.println("looking up " + url); 

      SampleInterface sample = (SampleInterface)Naming.lookup(url); 

      // args[2] onward are the strings we want to reverse 
      for (int i=2; i < args.length; ++i) 
       // call the remote method and print the return 
       System.out.println(sample.invert(args[i])); 
     } catch(Exception e) { 
      System.out.println("SampleClient exception: " + e); 
     } 
    } 
} 

SampleInterface ：

import java.rmi.Remote; 
import java.rmi.RemoteException; 

public interface SampleInterface extends Remote { 
    public String invert(String msg) throws RemoteException; 
} 

样品：

import java.rmi.Remote; 
import java.rmi.RemoteException; 
import java.rmi.server.*; 

// this is the class with remote methods 

public class Sample 
    extends UnicastRemoteObject 
    implements SampleInterface { 

    private int a; 

    public Sample() throws RemoteException { 
    System.out.println("New instance of Sample created"); 
    a = 1; 
    } 

    public String invert(String m) throws RemoteException { 
     // return input message with characters reversed 
     System.out.println("invert("+m+") a=" + a); 
     return new StringBuffer(m).reverse().toString(); 
    } 
} 

政策：

grant { 
    permission java.security.AllPermission; 
}; 

Answer 1

javaw rmiregistry 1099

停在那儿。这已经是错误的。 'rmiregistry'是一个可执行文件，而不是可以用'java'或'javaw'执行的Java类的名称。只需使用'rmiregistry'。

Answer 2

当端口上没有服务运行时，您尝试连接时发生此错误。正如EJP所说，rmiregistry是一个可以在后台（JDK 7）中由rmiregistry &启动的工具。我会建议你检查你的防火墙或端口连接问题。