内存溢出
元空间
public class MetaspaceOom {
// -XX:MetaspaceSize=10m -XX:MaxMetaspaceSize=10m
public static void main(String[] args) {
long counter = 0;
while (true) {
Enhancer enhancer = new Enhancer();
enhancer.setSuperclass(Car.class);
enhancer.setUseCache(false);
enhancer.setCallback(new MethodInterceptor() {
@Override
public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
if (method.getName().equals("run")) {
System.out.println("启动汽车之前先进行安全检查");
return methodProxy.invokeSuper(o, objects);
} else {
return methodProxy.invokeSuper(o, objects);
}
}
});
Car car = (Car) enhancer.create();
car.run();
System.out.println("创建了 " + (++counter) + " 个子类");
}
}
static class Car {
public void run() {
System.out.println("汽车启动，开始行驶");
}
}
}
Caused by: java.lang.OutOfMemoryError: Metaspace
at java.lang.ClassLoader.defineClass1(Native Method)
虚拟机栈
public class StackOom {
private static int stackLength = 0;
// -Xss1M
public static void main(String[] args) {
StackOom stackOom = new StackOom();
try {
stackOom.invoke();
} catch (Throwable e) {
System.out.println("stack length: " + stackLength);
throw e;
}
}
public void invoke() {
stackLength++;
invoke();
}
}
Exception in thread "main" java.lang.StackOverflowError
at com.javashitang.oomKind.StackOom.invoke(StackOom.java:24)
堆内存
public class HeapOom {
private static final int _1MB = 1024 * 1024;
// -Xms20m -Xmx20m
public static void main(String[] args) {
List<byte[]> list = Lists.newArrayList();
while (true) {
list.add(new byte[_1MB]);
}
}
}
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
at com.javashitang.oomKind.HeapOom.main(HeapOom.java:19)
堆外内存
public class DirectMemoryOom {
private static final int _1MB = 1024 * 1024;
// -XX:MaxDirectMemorySize=2m
public static void main(String[] args) {
ByteBuffer.allocateDirect(3 * _1MB);
}
}
Exception in thread "main" java.lang.OutOfMemoryError: Direct buffer memory
at java.nio.Bits.reserveMemory(Bits.java:694)
at java.nio.DirectByteBuffer.<init>(DirectByteBuffer.java:123)
at java.nio.ByteBuffer.allocateDirect(ByteBuffer.java:311)
at com.javashitang.oomKind.DirectMemoryOom.main(DirectMemoryOom.java:15)
参考博客
