java - 如何将 inputStream 对象发送到 Java EJBean？

Question

我有一个 session bean 的 Java 客户端，我想向它发送一个 inputStream，如下所示:

注意:我正在使用 EJB 3.0

public class SenderSimulator {

public static void main(String[] arg){
    Properties p = new Properties();
    p.put("java.naming.factory.initial", "org.jnp.interfaces.NamingContextFactory");
    p.put("java.naming.provider.url", "jnp://localhost:1099");
    p.put("java.naming.factory.url.pkgs", "org.jboss.naming:org.jnp.interfaces");

    try {
        Context context = new InitialContext(p);
        RogersBatchImporter  bean = (RogersBatchImporter)context.lookup("RogersImporterBean/remote");
        InputStream in = new FileInputStream("filePath");           
        System.out.println("Result: " + bean.processBatch(in));  // line 29
    } catch (NamingException e) {
        e.printStackTrace();
    } catch (LogConfigurationException e) {
        e.printStackTrace();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
}

但它抛出以下异常:

Exception in thread "main" java.lang.reflect.UndeclaredThrowableException

at $Proxy0.processBatch(Unknown Source)

at package.main(SenderSimulator.java:29)

Caused by: java.rmi.MarshalException: Failed to communicate.  Problem during marshalling/unmarshalling; nested exception is: 
    java.io.NotSerializableException: java.io.FileInputStream
    at org.jboss.remoting.transport.socket.SocketClientInvoker.handleException(SocketClientInvoker.java:127)
    at org.jboss.remoting.transport.socket.MicroSocketClientInvoker.transport(MicroSocketClientInvoker.java:689)
    at org.jboss.remoting.MicroRemoteClientInvoker.invoke(MicroRemoteClientInvoker.java:122)
    at org.jboss.remoting.Client.invoke(Client.java:1634)
    at org.jboss.remoting.Client.invoke(Client.java:548)
    at org.jboss.aspects.remoting.InvokeRemoteInterceptor.invoke(InvokeRemoteInterceptor.java:62)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.aspects.tx.ClientTxPropagationInterceptor.invoke(ClientTxPropagationInterceptor.java:67)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.aspects.security.SecurityClientInterceptor.invoke(SecurityClientInterceptor.java:53)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.ejb3.remoting.IsLocalInterceptor.invoke(IsLocalInterceptor.java:74)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.ejb3.stateless.StatelessRemoteProxy.invoke(StatelessRemoteProxy.java:107)
    ... 2 more
Caused by: java.io.NotSerializableException: java.io.FileInputStream
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1156)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1338)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1146)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:326)
    at java.rmi.MarshalledObject.<init>(MarshalledObject.java:101)
    at org.jboss.aop.joinpoint.MethodInvocation.writeExternal(MethodInvocation.java:318)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1421)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1390)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1509)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1474)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:326)
    at org.jboss.remoting.serialization.impl.java.JavaSerializationManager.sendObjectVersion2_2(JavaSerializationManager.java:120)
    at org.jboss.remoting.serialization.impl.java.JavaSerializationManager.sendObject(JavaSerializationManager.java:95)
    at org.jboss.remoting.marshal.serializable.SerializableMarshaller.write(SerializableMarshaller.java:120)
    at org.jboss.remoting.transport.socket.MicroSocketClientInvoker.versionedWrite(MicroSocketClientInvoker.java:969)
    at org.jboss.remoting.transport.socket.MicroSocketClientInvoker.transport(MicroSocketClientInvoker.java:606)
    at org.jboss.remoting.MicroRemoteClientInvoker.invoke(MicroRemoteClientInvoker.java:122)
    at org.jboss.remoting.Client.invoke(Client.java:1634)
    at org.jboss.remoting.Client.invoke(Client.java:548)
    at org.jboss.aspects.remoting.InvokeRemoteInterceptor.invoke(InvokeRemoteInterceptor.java:62)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.aspects.tx.ClientTxPropagationInterceptor.invoke(ClientTxPropagationInterceptor.java:67)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.aspects.security.SecurityClientInterceptor.invoke(SecurityClientInterceptor.java:53)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.ejb3.remoting.IsLocalInterceptor.invoke(IsLocalInterceptor.java:74)
    at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
    at org.jboss.ejb3.stateless.StatelessRemoteProxy.invoke(StatelessRemoteProxy.java:107)
    at $Proxy0.processBatch(Unknown Source)
    at com.cybersource.rogers.batch.request.SenderSimulator.main(SenderSimulator.java:29)
    at org.jboss.aspects.remoting.InvokeRemoteInterceptor.invoke(InvokeRemoteInterceptor.java:74)
    ... 10 more

Answer 1

正如其他人指出的那样，File、InputStream 和许多其他与 IO 相关的对象不可序列化，因此无法跨越客户端和服务器之间的连接(没有附加功能)。在 J2EE 上下文中，容器应尽快完成流程，以最大限度地减少资源使用并允许并行处理。在 Java 的 NIO 之前，I/O 操作通常被阻塞(等待读取或写入数据)，这会导致线程挂起(即，最好的情况是暂时停止运行，最坏的情况是永久停止运行)。

我曾经参与过一个项目，其中一些对 Java 相当陌生的实现者打开了从 EJB 到远程服务器的 FTP 连接——违背了我和 J2EE 文档中的警告。当远程服务器没有响应时，取消挂起我们服务器的唯一方法是杀死并重新启动它!

因此:在客户端抓取文件内容并将其作为大字符串、字符或字节数组或其他内容通过连接传送。这样，您的 EJB 进程将准备好所有数据以供处理。

如果数据量太大而无法在合理的内存量中执行此操作，那么这不是一个可行的解决方案。在这种情况下，推荐的解决方案是让客户端将数据写入数据库(可能是 BLOB)并从数据库中读取 EJB。