metaspace

Main.java

package meta;

import org.springframework.cglib.proxy.Enhancer;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;

import java.lang.reflect.Method;

/**
 * @author Frank
 * @date 2020/4/25 23:32
 */
public class Main {
    static class demo{

    }

    //-XX:MetaspaceSize=10m -XX:MaxMetaspaceSize=10m -XX:+PrintGCDetails
    public static void main(String[] args) {

        while (true) {
            Enhancer enhancer = new Enhancer();
            enhancer.setSuperclass(demo.class);
            enhancer.setUseCache(false);
            enhancer.setCallback(new MethodInterceptor() {
                @Override
                public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
                    //动态代理创建对象
                    return methodProxy.invokeSuper(o, objects);
                }
            });
            enhancer.create();
        }
    }
//    public static void main(String[] args) {
//        System.getProperties().put("sun.misc.ProxyGenerator.saveGeneratedFiles", "true");
//
//        // jdk动态代理测试
//        Subject subject1 = new JDKDynamicProxy(new RealSubject()).getProxy();
//        Subject subject2 = new JDKDynamicProxy(new RealSubject2()).getProxy();
//        subject1.doSomething();
//        subject2.doSomething();
//        while (true){
//             Object i = new JDKDynamicProxy(new RealSubject()).getProxy();
//        }
//    }
}

gclib动态代理类不断创建，导致metaspace溢出，OOM。下面jdk代理类并没有导致这个问题，因为一直都是Proxy0这个类，没有创建新的类。