package com.ashu.test;
import sun.misc.Signal;
import sun.misc.SignalHandler;
@SuppressWarnings("restriction")
public class TestSignal implements SignalHandler {
private void signalCallback(Signal sn) {
System.out.println(sn.getName() + "is recevied.");
}
@Override
public void handle(Signal signalName) {
signalCallback(signalName);
}
public static void main(String[] args) throws InterruptedException {
TestSignal testSignalHandler = new TestSignal();
// install signals
Signal.handle(new Signal("TERM"), testSignalHandler);
Signal.handle(new Signal("USR1"), testSignalHandler);
Signal.handle(new Signal("USR2"), testSignalHandler);
for (;;) {
Thread.sleep(3000);
System.out.println("running......");
}
}
}
testSignal重写了SignalHandler的handle方法,捕获到的kill信号也是最终在handle里处理。
在main里注册了三个kill信号:TERM(kill -15)、USR1(kill -10)、USR2(kill -12)
补充1:
在Linux下支持的信号(具体信号kill -l命令查看):
SEGV, ILL, FPE, BUS, SYS, CPU, FSZ, ABRT, INT, TERM, HUP, USR1, USR2, QUIT, BREAK, TRAP, PIPE
在Windows下支持的信号:
SEGV, ILL, FPE, ABRT, INT, TERM, BREAK
补充2:
运行中可能会抛出异常:
java.lang.IllegalArgumentException: Signal already used by VM: USR1
这是因为某些信号可能已经被JVM占用,可以考虑用其它信号代替