netty epoll native throw java.lang.IllegalArgumentException in linux(debian)

Question

When start application, the following exception is thrown from netty

Caused by: java.lang.IllegalArgumentException
    at sun.misc.Unsafe.allocateMemory(Native Method)
    at io.netty.util.internal.PlatformDependent0.allocateMemory(PlatformDependent0.java:627)
    at io.netty.util.internal.PlatformDependent.allocateMemory(PlatformDependent.java:262)
    at io.netty.channel.epoll.IovArray.<init>(IovArray.java:64)
    at io.netty.channel.epoll.EpollEventLoop.<init>(EpollEventLoop.java:62)
    at io.netty.channel.epoll.EpollEventLoopGroup.newChild(EpollEventLoopGroup.java:130)
    at io.netty.channel.epoll.EpollEventLoopGroup.newChild(EpollEventLoopGroup.java:35)
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:84)

Answer 1

The reason is caused by another library which contains the android-2.3.3.jar. Netty EPOLL native try to detect the system by checking the functions & class. In the PlatformDependent::isAndroid0(), because of the android jar, it will believe itself is running in android.

 private static boolean isAndroid0() {
    boolean android;
    try {
        Class.forName("android.app.Application", false, getSystemClassLoader());
        android = true;
 ...

So the function hasUnsafe0() will wrongly believe there is no sun.misc.Unsafe.

private static boolean hasUnsafe0() {
    if(isAndroid()) {
        logger.debug("sun.misc.Unsafe: unavailable (Android)");
        return false;

Because of this, the exception is thrown when it is calling the native memory allocation. Its parameter is negative value!!!