java - 如何修复 Android Studio 中的 ChannelException？

Question

我想在 Android 设备上测试 io.netty(库)。但是当我运行该应用程序时，它会抛出 io.netty.channel.ChannelException。

我的调试器不会停在我设置 Netty-Bootstrap 的行上，程序在...之前崩溃(我也不明白)。 我更深入地研究了后台代码，似乎 Android 开发人员更改了 Constructer.newInstance() 方法，这似乎是我的问题的原因。但我不知道为什么会抛出该异常以及如何避免这种情况。

这是客户端的设置(问题是 NioServerSocket.class， 无法实例化)

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;

public class NettyBootstrap {


    private MainActivity parent;

    public NettyBootstrap(MainActivity main) {
        parent = main;

        EventLoopGroup workerGroup = new NioEventLoopGroup();

        try {
            new Bootstrap()
                    .group(workerGroup)
                    .channel(NioSocketChannel.class)
                    .handler(new ChannelInitializer<SocketChannel>() {

                        @Override
                        protected void initChannel(SocketChannel ch) throws Exception {
                            ch.pipeline()
                                    .addLast(new StringEncoder())
                                    .addLast(new StringDecoder())
                                    .addLast(new OwnChannelHandler(parent));
                        }
                    }).connect("localhost", 26666).sync().channel().closeFuture().syncUninterruptibly();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            workerGroup.shutdownGracefully();
        }
    }
}

这是我的错误日志的一部分:

Caused by: io.netty.channel.ChannelException: Unable to create Channel from class class io.netty.channel.socket.nio.NioSocketChannel
        at io.netty.channel.ReflectiveChannelFactory.newChannel(ReflectiveChannelFactory.java:46)
        at io.netty.bootstrap.AbstractBootstrap.initAndRegister(AbstractBootstrap.java:320)
        at io.netty.bootstrap.Bootstrap.doResolveAndConnect(Bootstrap.java:163)
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:145)
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:126)
        at com.pxif.connectiontest.nio.NettyBootstrap.<init>(NettyBootstrap.java:43)
        at com.pxif.connectiontest.MainActivity.onCreate(MainActivity.java:24)

编辑

我的整个错误日志(我仍然遗漏了 Android zygote 的内容):

E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.pxif.connectiontest, PID: 5485
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.pxif.connectiontest/com.pxif.connectiontest.MainActivity}: io.netty.channel.ChannelException: Unable to create Channel from class class io.netty.channel.socket.nio.NioSocketChannel
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2817)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
        at android.os.Handler.dispatchMessage(Handler.java:105)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6541)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
     Caused by: io.netty.channel.ChannelException: Unable to create Channel from class class io.netty.channel.socket.nio.NioSocketChannel
        at io.netty.channel.ReflectiveChannelFactory.newChannel(ReflectiveChannelFactory.java:46)
        at io.netty.bootstrap.AbstractBootstrap.initAndRegister(AbstractBootstrap.java:320)
        at io.netty.bootstrap.Bootstrap.doResolveAndConnect(Bootstrap.java:163)
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:145)
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:126)
        at com.pxif.connectiontest.nio.NettyBootstrap.<init>(NettyBootstrap.java:37)
        at com.pxif.connectiontest.MainActivity.onCreate(MainActivity.java:24)
        at android.app.Activity.performCreate(Activity.java:6975)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) 
        at android.os.Handler.dispatchMessage(Handler.java:105) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6541) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767) 
     Caused by: java.lang.reflect.InvocationTargetException
        at java.lang.reflect.Constructor.newInstance0(Native Method)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
        at io.netty.channel.ReflectiveChannelFactory.newChannel(ReflectiveChannelFactory.java:44)
        at io.netty.bootstrap.AbstractBootstrap.initAndRegister(AbstractBootstrap.java:320) 
        at io.netty.bootstrap.Bootstrap.doResolveAndConnect(Bootstrap.java:163) 
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:145) 
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:126) 
        at com.pxif.connectiontest.nio.NettyBootstrap.<init>(NettyBootstrap.java:37) 
        at com.pxif.connectiontest.MainActivity.onCreate(MainActivity.java:24) 
        at android.app.Activity.performCreate(Activity.java:6975) 
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213) 
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770) 
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) 
        at android.os.Handler.dispatchMessage(Handler.java:105) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6541) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767) 
     Caused by: io.netty.channel.ChannelException: Failed to open a socket.
        at io.netty.channel.socket.nio.NioSocketChannel.newSocket(NioSocketChannel.java:70)
        at io.netty.channel.socket.nio.NioSocketChannel.<init>(NioSocketChannel.java:87)
        at io.netty.channel.socket.nio.NioSocketChannel.<init>(NioSocketChannel.java:80)
        at java.lang.reflect.Constructor.newInstance0(Native Method) 
        at java.lang.reflect.Constructor.newInstance(Constructor.java:334) 
        at io.netty.channel.ReflectiveChannelFactory.newChannel(ReflectiveChannelFactory.java:44) 
        at io.netty.bootstrap.AbstractBootstrap.initAndRegister(AbstractBootstrap.java:320) 
        at io.netty.bootstrap.Bootstrap.doResolveAndConnect(Bootstrap.java:163) 
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:145) 
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:126) 
        at com.pxif.connectiontest.nio.NettyBootstrap.<init>(NettyBootstrap.java:37) 
        at com.pxif.connectiontest.MainActivity.onCreate(MainActivity.java:24) 
        at android.app.Activity.performCreate(Activity.java:6975) 
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213) 
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770) 
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) 
        at android.os.Handler.dispatchMessage(Handler.java:105) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6541) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767) 
     Caused by: java.net.SocketException: Permission denied
        at sun.nio.ch.Net.socket0(Native Method)
        at sun.nio.ch.Net.socket(Net.java:420)
        at sun.nio.ch.Net.socket(Net.java:413)
        at sun.nio.ch.SocketChannelImpl.<init>(SocketChannelImpl.java:128)
        at sun.nio.ch.SelectorProviderImpl.openSocketChannel(SelectorProviderImpl.java:60)
        at io.netty.channel.socket.nio.NioSocketChannel.newSocket(NioSocketChannel.java:68)
        at io.netty.channel.socket.nio.NioSocketChannel.<init>(NioSocketChannel.java:87) 
        at io.netty.channel.socket.nio.NioSocketChannel.<init>(NioSocketChannel.java:80) 
        at java.lang.reflect.Constructor.newInstance0(Native Method) 
        at java.lang.reflect.Constructor.newInstance(Constructor.java:334) 
        at io.netty.channel.ReflectiveChannelFactory.newChannel(ReflectiveChannelFactory.java:44) 
        at io.netty.bootstrap.AbstractBootstrap.initAndRegister(AbstractBootstrap.java:320) 
        at io.netty.bootstrap.Bootstrap.doResolveAndConnect(Bootstrap.java:163) 
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:145) 
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:126) 
        at com.pxif.connectiontest.nio.NettyBootstrap.<init>(NettyBootstrap.java:37) 
        at com.pxif.connectiontest.MainActivity.onCreate(MainActivity.java:24) 
        at android.app.Activity.performCreate(Activity.java:6975) 
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213) 
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770) 
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) 
        at android.os.Handler.dispatchMessage(Handler.java:105) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6541) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767) 
I/zygote: Background concurrent copying GC freed 9292(1386KB) AllocSpace objects, 0(0B) LOS objects, 58% free, 1077KB/2MB, paused 35.531ms total 135.042ms
E/System: Uncaught exception thrown by finalizer
E/System: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.io.FileDescriptor.isSocket$()' on a null object reference
        at sun.nio.ch.FileDispatcherImpl.preCloseImpl(FileDispatcherImpl.java:115)
        at sun.nio.ch.SocketDispatcher.preClose(SocketDispatcher.java:66)
        at sun.nio.ch.SocketChannelImpl.implCloseSelectableChannel(SocketChannelImpl.java:883)
        at java.nio.channels.spi.AbstractSelectableChannel.implCloseChannel(AbstractSelectableChannel.java:234)
        at java.nio.channels.spi.AbstractInterruptibleChannel.close(AbstractInterruptibleChannel.java:116)
        at sun.nio.ch.SocketChannelImpl.finalize(SocketChannelImpl.java:937)
        at java.lang.Daemons$FinalizerDaemon.doFinalize(Daemons.java:250)
        at java.lang.Daemons$FinalizerDaemon.runInternal(Daemons.java:237)
        at java.lang.Daemons$Daemon.run(Daemons.java:103)
        at java.lang.Thread.run(Thread.java:764)

感谢您的帮助:D

Answer 1

我可以看到打开套接字时出现权限被拒绝的异常。

尝试添加

    <uses-permission android:name="android.permission.INTERNET"/>

到您的 list 。